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NEWDOS/80
  		• Booting NewDos/80 v2.0 on a Model 4P
  		• NewDos/80 v2.0 /SYS File Guide
  		• NewDos/80 v2.0 Other-DOS PDRIVE Settings
  		• Setting HIMEM from NEWDOS/80 v2.0 BASIC
  		• Model III Self-Booting Disk using NEWDOS/80
  		• Reading Model 4 TRSDOS or Model III LDOS disk on NEWDOS/80
  		• Trading Files Between LDOS6.2 and NEWDOS/80 v2
  		• Configuring LDOS like NEWDOS/80
  		• Modifying the AMPERSAND Command in NEWDOS/80 BASIC
    LDOS
  		• Using LDOS as a Host (Communications)
  		• Creating /CMD Files from LDOS LIB Commands
  		• Increasing The Number of Drives in LDOS
  		• Booting A Double-Sided Diskette Under LDOS 5.1.x and 6.x
  		• Reading Model 4 TRSDOS or Model III LDOS disk on NEWDOS/80
  		• Using TRSDOS or LDOS to Write Protect
  		• Trading Files Between LDOS6.2 and NEWDOS/80 v2
  		• Configuring LDOS like NEWDOS/80
    TRSDOS
  		• Guided Tour Through The Model III TRSDOS Directory
  		• Reading Model 4 TRSDOS or Model III LDOS disk on NEWDOS/80
  		• Formatting A Double-Sided Diskette Under TRSDOS 6.x
  		• Defeating TRSDOS v6.x Backup Protection
  		• Using TRSDOS or LDOS to Write Protect
  		• TRSDOS 6.2 Routine Addresses
  		• Running SYSTEM Commands from Model 4 BASIC
  		• Renaming DOS Commands
    Hard Drive
  		• Using a Single Hard Drive with 2 Operating Systems
  		• Initializing Hard Drives under Model IV DOS's
  		• Change The Minimum Cluster Size on R/S Hard Drives
  		• Booting a Model 4P from a Hard Drive
  		• Changing TRSDOS 6.2.1 to Boot a Model 4P from a Hard Drive
    Misc
  		• Passwords
  		• System functions that can be accomplished in BASIC


             Using a Single Hard Drive with 2 Operating Systems
    PowerSOFT Products
    11500 Stemmons Expressway, Suite 125
    Dallas TX 75229
    (214) 484-2976
    The Model 4/4P computer has the capability of running in two modes: Model III mode and Model 4 mode. This allows a Model 4/4P owner to use two (or more) different operating operating systems on the computer. Two operating systems, one for each mode of operation, are available from Radio Shack for use on the Model 4/4P with a Radio Shack 5-megabyte hard drive: TRSDOS 6 for Model 4 mode, and LDOS 5.1 for Model III mode. The question has arisen among users of the 5-megabyte hard drive of whether there is any way to use both operating systems on the same hard drive without having to reformat and recreate the system partition every time. There is some justification for wanting to do this. The two operating systems involved, LDOS 5.1 for the Model III mode and TRSDOS 6.1 for the Model 4 mode, are very similar. Moreover, since the software base for TRSDOS 6 is not yet as large as that for LDOS, it can be to a user's advantage to switch to LDOS to run applications which are not available for TRSDOS 6. Finally, a hard drive system provides extensive storage capacity as well as increased operating speed over floppy disks. It seems a waste to have to switch to floppies just to run a particular application.
    We at PowerSOFT have been able to place both the LDOS and TRSDOS 6 operating systems on a single hard drive so that they can be used by a Model 4 running in either mode. The selection of which system to utilize is done by simply booting up the appropriate floppy system disk and letting the configuration file transfer control to the hard disk. The files on the hard disk are accessible to both operating systems. This was made possible by the media compatibility which exists between LDOS and TRSDOS 6. This means that they can read each other's directories and disk formats without requiring special software.
    The key to placing both operating systems on a single hard drive lies in the flexibility of the two operating systems. Both LDOS and TRSDOS 6 allow you to split up a hard drive into one or more logical drives; and the logical drive numbers need not be the same as the physical positions of the hard disk partitions. This is what makes it all work. The hard disk partition which is assigned as Drive 0 for LDOS need not be the same as the partition which is assigned as Drive 0 for TRSDOS 6! This means that TWO independent logical drive zeros (system drives) can exist on a single hard drive, one for each operating system. And of course, each operating system sees only its own drive 0, the other one appearing to it as something else.
    Once this concept is understood, the application of it is quite simple.
    Consider the setup of a 5-megabyte hard drive system. Each hard drive contains two disks or platters, each with two surfaces (four surfaces in all). Each surface has its own read/write head. Both LDOS and TRSDOS 6 allow us to split the hard drive along the surfaces (sometimes referred to as the "head offset method," head referring to the individual read/write head of each surface). This means that we can split a hard drive into a maximum of four logical drives, assigning one surface ("head") to each. This is what happens when we execute the Model 4 hard disk initialization program. The hard disk is split into four logical drives, the first surface being drive :0, the second drive :1, the third drive :2, and the fourth drive :3.
    There is nothing in either operating system which says that Surface Number One must be logical drive 0 always. So what we can now do is run a modifiedinitialization file under LDOS that reverses the order of logical drives :0 and :3.That is, surface four becomes drive :0, and surface number one becomes drive :3. Thuswe can have two different drive zeros on the hard drive. But the drive :0 which isthe system drive when TRSDOS 6 is running is drive :3 when LDOS running and viceversa. Voila, we have two operating systems sharing the same hard drive! And sinceonly one operating system can be running at any one time, there is no conflictbetween them. Consider the diagram below. 
        TRSDOS 6 sees ==>    :0    :1     2      :3
    PHYSICAL SURFACE      1     2     3       4
    LDOS 5.1 sees ==>    :3    :1     :2     :0
    Of course, it falls on the user of such a shared system to make sure thatprograms which run only under one operating system or the other are clearly andobviously marked. One way to accomplish this is to place model- specific programfiles on each operating system's respective drive 0, and have data files (which canusually be read by both systems) resident on the other two logical drives. Or filescan be renamed so that those intended for LDOS (Model III mode) only end with "M3"while those intended for TRSDOS 6 (Model 4 mode) only end with "M4." There are many possible schemes to choose from and you should select one which suits your particularsituation best.
    We present below a three-step procedure to implement the method just described, for those Model 4 hard drive owners who wish to use both LDOS and TRSDOS. Please makesure that you backup EVERY file on your hard drive before you implement this procedu re, as the hard drive will be reformatted.
    To use this procedure, you must have both the TRSDOS 6 hard drive initialization disk as well as the LDOS hard drive initialization disk available.
    STEP ONE. Boot up your TRSDOS 6 Hard Drive Initialization Disk. This will automa tically execute the initialization program. Follow the steps described in your Hard Disk Startup Manual. Tell the program that you to create a hard drive system with eq ual partition sizes, the hard disk to be the system device, and the hard disk to be s earched FIRST when looking for a file. This will result in the hard drive logical dr ive numbers as 0, 1, 2, and 3. Proceed to format the hard drive, move files over to it, and create your BOOT diskette. These procedures are all described in the Hard Di sk Startup Manual.
    STEP TWO. Make a BACKUP of your LDOS Hard Drive Initialization disk. Boot up thi s disk but do NOT execute the initialization procedure yet. We must modify the Model III Hard Disk Initialization files, using the PATCH command of LDOS. First type: BU ILD INITHD3/FIX. Then type in the patch lines below EXACTLY. 
        .Patch to INITHD3/JCL to reverse head order and skip
    .FORMAT
    D09,B8="1"
    D09,EB="4"
    D0E,6F="."
    D0E,9C="."
    D0E,C9="."
    .End of Patch.
    Now press BREAK. The patch file will be written to disk. Now type: PATCH INITHD3/JCL USING INITHD3/FIX and press ENTER. The patch will be applied to the INITHD3/JCL file. There is one more patch which needs to be applied. Since it is very short, you will not build a separate patch file for it, but simply type it in on the command line. Type: 
               PATCH HD1/CFG.CCC (D02,F7=13:D03,15=10)
    And press ENTER. The patch will be applied to HD1/CFG.
    You have just patched the LDOS Hard Disk Initialization files to (a) reverse the order of logical drives :0 and :3 on the hard disk, and (b) skip the formatting process (since we've already formatted the hard drive under TRSDOS 6).
    STEP THREE. Execute the patched LDOS (Model III) Hard Disk Initialization with the command, 
        DO INITHD3 (NEW,PW=PASSWORD,HARD1,FLOPPY2,ABS).
    Refer to the Model III Hard Disk Startup Manual, page 31 and following, for more details.
    You now have a hard drive shared between LDOS and TRSDOS 6. Selection is automatic depending on which boot disk is in the floppy drive when the reset button is pressed. When you are running TRSDOS 6, you will note that your logical drive :3 has the LDOS system files on it. When running LDOS in Model III mode, logical drive :3 will have the TRSDOS 6 system files on it. Logical drives :1 and :2 will be the same regardless of which operating system is currently running. This way, any programs which reference files on these two logical drives will not need to be changed.
    Using this method, you will be able to use a Model 4 or 4P system with a hard disk to its maximum capability, rather than having to use one operating system on a hard disk and the other on floppies (or on another hard disk). The same method works on larger-capacity hard drives as well, if you have them hooked up to a Model 4 or 4P computer. Unfortunately this method is not usable with CP/M Plus, since CP/M Plus does not have the capability of splitting a hard drive into several logical drives; it sees a hard drive as a single volume only.
    The same technique is used to create different system partitions that will be used by two or more computers in a multiplexed situation. In this type of environment, several computers share the same hard drive, and the hard drive is split up so that each computer has its own system partition. These system partitions may be set up so that they are invisible to the other computers, in order to prevent accidental alteration of the system files. In order to maximize the use of available storage space, a hard disk driver program which permits a type of partitioning known as cylinder offset is preferable. Using such a driver, the size of the system partitions can be limited to the minimum necessary to hold the operating system modules and a few often-used (and machine-specific) utilities, leaving the rest as sharable storage between the various computers.
    If you have a hard drive which uses a Western Digital controller board, contact PowerSOFT at the address above for more information on hard disk drivers and other hard drive utility software.

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             How to use LDOS for Host Work - Michael Cooper
    One of the features of LDOS that make it a superior operating system is the device independence. This allows you total flexibility in the way you can set up the system I/O. In the case of CLUB-80 I needed to include a communications link to the operating system, but still protect the integrity of the applications programs and files.
    The Standard Devices in LDOS are : 
              *KI = Keyboard
          *DO = Video Display
          *PR = Printer
          *SI = System Input (Unassigned)
          *SO = System Output (Unassigned)
          *JL = Job-log (Unassigned)
    LDOS comes supplied with a Serial Device Driver for use with the RS-232 Port.The Model 3 version of the driver(RS232T/DVR) is very sophisticated, with an input buffer of 128 bytes and interrupt handling of incoming characters. To set the driver for use with a MODEM you must specify the Baud Rate and Byte configuration. 
              SET *CL TO RS232T (B=300,W=8,S=1,P=N,DTR,RTS)
    This will create a new device called *CL- Comm Line that uses RS232T as its driver program. The parameters passed in the parentheses set Baud Rate = 300, Word length = 8 Bits, Stop Bit = 1, No Parity Bit, sets DTR and RTS to logical "TRUE". Now by connecting a MODEM to the RS-232 Serial port you have a pathway for data to and from the Telephone.
    The remaining task is to connect the *CL device into LDOS. This can be achieved in several ways,but in this case we want to use the system in remote mode, so we connect *CL to the *KI (Keyboard) device for input, and to *DO (Display) device for output. In LDOS this is done by: 
              LINK *CL *KI 
          LINK *CL *DO
    This permits any request for keyboard input via *KI Keyboard to be serviced either by the keyboard of the HOST machine or via MODEM through *CL. Any character output to *DO (Display) will also be sent to *CL and thus to the MODEM, this provides the ECHO.
    As an added bonus, the LDOS Type-ahead Keyboard Driver allow double buffering of all input via *CL. Data from the MODEM is fetched by the interrupt handler as soon as it arrives, and buffered until the next scan of th typeahead routine. The data is then buffered for use by the *KI driver when needed.
    To complete this operation, the whole of high memory and the DCB's are saved in the CONFIG file for loading at Boot. All is now prepared so the computer can be used remotely via the phone. All the programs it will run can be written in BASIC and do whatever you want.
    The CLUB-80 software is written in LBASIC and the programs run in "EXEC" mode(Level 7) to afford maximum protection from tampering. As an added protection a FILTER program is used on the *KI (Keyboard) device to check that the system hasn't somehow dropped into DOS READY or BASIC READY. If the FILTER finds this condition true, the system is rebooted to disconnect the current caller before they can play around.

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             Increasing The Number of Drives in LDOS - Frank Durda IV
    To turn floppies 2 & 3 on immediately, but only for the current session:
    system (drive=2,enable)
    
system (drive=3,enable)
    To make this permanent, SYSGEN these settings or make these commands part of the boot jcl.

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             Booting NewDos/80 v2.0 on a Model 4P

    Chris Anderson


    Note! This procedure is NOT necessary for a Model 4! It is only of use for Model 4P owners!
    You who own Model 4P's probably know by now that you are missing something that a Model 4 owner finds very handy - THE MODEL 3 ROM! Without that ROM, you cannot directly boot several other popular operating systems. To boot them, you must first boot using a disk that contains a file called MODELx/III. Most systems came with MODELA/III. Then you must reboot using the operating system of your choice. MODELA/III is a copy of the Model 3 ROM, and is loaded down in low memory, making it appear to the machine exactly as it would if there really WAS a ROM down there as there is on a Mod 3. By doing this, operating systems other than LDOS and CPM have the ROM routines available as needed for operation.
    SO... HOW to get a 4P to boot NEWDOS directly without first having to boot LDOS, load MODELA/III, and boot again? Easy.. fool the system (what else?) The following procedure creates a pseudo-directory on a NEWDOS disk. This directory will be properly located on track 20 so that it can be found by the bootstrap routine in the 4P. Immediately following the pseudo-directory will be a copy of MODELA/III. Both will be saved together as a single file. This file will also be entered into the REAL NEWDOS directory (so we don't accidently overwrite it with other files) and just so that you know what it is, it'll be called MODELA/III.
    So what happens? When LDOS tries to boot the disk, it finds an entry for MODELA/III in the area of the disk where LDOS looks for the directory. This dummy directory points a little further down into the file where MODELA/III actually exists! Confused? What can I say. Trust me on this one folks; it works.
    Boot the system as follows using LDOS6.2 This technique is the norm for booting foreign systems on the 4P.
    a)Install any LDOS6.2 disk that contains the program MODELA/III, assuming you have one so prepared. If so, you will be prompted to install the disk containing the foreign system (NEWDOS, in this case) and you may skip the next step. If not, use your MODELA/III disk to boot, following step b) instead.
    b)Insert your MODELA/III and press the reset button. IMMEDIATELY press and hold down the F3 and P keys. You will then receive the prompt to switch disks.
    c)Install a VIRGIN copy of NEWDOS80 V2 in Drive 0. It should contain the NEWDOS program called SUPERZAP/CMD and ALL /SYS files should be present.
    d)Set the PDRIVE for Drive 1 as follows: 
    		PDRIVE 0,1,DDSL=29,A
    e)Format and copy the disk on 0 to 1 as follows, using whatever you like for the current date:
    		COPY 0,1,11/25/87,CBF,/SYS,FMT
    f)Remove the virgin disk and install the newly created NEWDOS disk into Drive 0. Put the virgin disk into Drive 1 so you'll have use of the SUPERZAP program.
    g)Create a file entry called MODELA/III as follows:
    		CREATE MODELA/III:0
    h)Use SUPERZAP to modify the directory entry for MODELA/III on the disk in Drive 1 as noted below. If you have used a virgin disk, you will find the directory entry for MODELA/III at disk sector 299.
          FROM: 1000 0000 004D 4F44 454C 4120 2049 4949
            9642 9642 0000 FFFF FFFF FFFF FFFF FFFF
      TO:   1000 0000 004D 4F44 454C 4120 2049 4949
            9642 9642 0000 3600 FFFF FFFF FFFF FFFF
    The only actual change is the 4th pair on the second line of the entry from FFFF to 3600.
    i)Remove the virgin disk from Drive 1 and install the disk that came with your Model 4P system called MODELA/III. (Yeah, I know it's an LDOS disk. Be cool..)
    j)Check to make sure your PDRIVE setting is as noted below on Drive 0, entry for Drive 4 (it will be if you're using a virgin disk like I told you to!)
    			TI=AM,TD=E,TC=40,SPT=18,TSR=3,GPL=6,DDSL=17,DDGA=2
    k)If not, fix it!
    l)Copy the program MODELA/III to the NEWDOS disk with the following command:
    		COPY MODELA/III:1 :0 SPDN=4
    m)Remove the MODELA/III disk from Drive 1 and reinstall the disk containing SUPERZAP.
    n)Using SUPERZAP, Copy Disk Sectors (CDS) on Drive 0. You want to copy 10 sectors from 290 to 522. This makes a duplicate directory up in an unused region.
    o)Using SUPERZAP, modify the entry for MODELA/III in the "fake" directory as follows. You should find the entry in drive relative sector 531.
          FROM: 1020 0000 004D 4F44 454C 4120 2049 4949
            9642 9642 3900 360B FFFF FFFF FFFF FFFF
      TO:   1000 0000 004D 4F44 454C 4120 2049 4949
            9642 9642 3900 1E09 FFFF FFFF FFFF FFFF
    Note that the only actual changes were from 1020 to 1000 in the top line, and from 360B to 1E09 in the second line.
    p)Using SUPERZAP, modify the entry for MODELA/III in the REAL directory as follows. The entry will be at drive relative sector 299 like it was the first time you diddled with it:
          FROM: 1020 0000 004D 4F44 454C 4120 2049 4949
            9642 9642 3900 360B FFFF FFFF FFFF FFFF
      TO:   1000 0000 004D 4F44 454C 4120 2049 4949
            9642 9642 4D00 340F FFFF FFFF FFFF FFFF
    Note that the changes here are from 1020 to 1000 in the first line, and from 3900 to 4D00 and from 360B to 340F in the second line.
    q)Since you have a virgin copy of NEWDOS in Drive 1 (right?) you should have DIRCHECK/CMD on it as it came from Apparat. Execute DIRCHECK, specifying Drive 0 as the target drive. Everything being the way it ought to be, you should get the following error messages at the end of the program:
          34,0 ***** GRANULE FREE, BUT ASSIGNED TO FILE(S)...
      34,1 *****  "
      35,0 *****  "   (Each should be shown as assigned
      35,1 *****  "    to FILE(S) 67 MODELA/III.)
      36,0 *****  "
    r)Using SUPERZAP, go to the GAT sector (drive relative sector 290) and correct the errors caught by running DIRCHECK:
          Change relative byte 34 from FC to FF
      Change relative byte 35 from FC to FF
      Change relative byte 36 from FE to FF
    ALL DONE! You now have a bootable NEWDOS disk. When you remember what life is like without the PDRIVE command, you'll believe it was worth it!

    Another Method by Russ McElroy, CIS 72235,615


    You will need two SS 40 track disk drives, NEWDOS80 (and SUPERZAP), and a TRSDOS 6.x system disk (with MODELA/III). What we will do is create a new system file 'SYS22/SYS' which will consist of the MODELA/III file preceeded by a mock TRSDOS 1.3 FPDE positioned so the 4P will find it on bootup. The 4P will use this mock directory entry to locate the ROM image and will then proceed to load it, thereby booting without the use of a TRSDOS 1.3 diskette!
    One caveat: I tried using the MODELA/III file supplied with LSDOS 6.3, but found it would not work correctly. Using the original version I got with my 4P solved the problem. If, upon booting your zapped NEWDOS80 system, you find yourself with no repeat keys (ie. hold down a key and see if it repeats), it is likely you'll need to use an older version of MODELA/III.
    1.Boot up a NEWDOS80 system and set up the PDRIVE table to copy the system: PDRIVE 0,1=0. Press reset to load the new pdrive info.
    2.Make a backup of the NEWDOS80 system onto a disk in drive 1 using:
    	COPY,0,1,,CBF,FMT,/SYS,NDMW
    This copies only /SYS files onto the new system disk.
    3.Put the mock TRSDOS 1.3 FPDE on the new system disk using SUPERZAP.
    At DRS 308, starting at byte 00 enter the following bytes: 
    	100A 5400 004D 4F44 454C 4120 2049 4949
	9642 9642 3900 1133 FFFF FFFF FFFF FFFF
    4.Update the GAT to reflect the space to be occupied by the SYS22/SYS file.
    At DRS 170, starting at byte 1EH enter the following bytes: 
    	FEFF FFFF FFFF FF
    This lets the system know that this space is occupied.
    5.Add the HIT entry for the SYS22/SYS file.
    At DRS 171, byte 60H enter the following byte 
    	25
    This is the hash code for 'SYS22/SYS' in the proper position so the system can locate the FPDE.
    6.Use the CDS function of SUPERZAP to copy the 57 sectors of the MODELA/III file from a TRSDOS 6.x system disk to the new system disk.
    To do this, mount the TRSDOS disk in drive 0 and copy 57 sectors from DRS 660 of the TRSDOS disk to DRS 312 of the new NEWDOS80 system disk in drive 1.
    That's all there is to it!

    Another Method


    The MODELA/III file must be loaded from a diskette in the TRSDOS 1.x, LDOS 5 or LS-DOS 6.x format. The 4P Boot ROM doesn't understand any of the other directory/filesystem layouts, and by default the NEWDOS disk format is quite different.*
    The normal process for booting an "alien" format diskette is: 
    1.	Insert the diskette with MODELA/III on it and press reset.
2.	If that diskette is LS-DOS 6, press the [3] or [F3] key within three
	seconds.
3.	Press the [P] key to indicate that you want to swap diskettes.
	You must also do this within the three seconds after pressing RESET.
	(You can press the F3, 3 and P keys in any order or all at once.)
4.	The system prompts to change diskettes.  Insert NEWDOS, MultiDOS
	or whatever non-TRSDOS/non-LDOS format OS this is.
5.	Press [ENTER] to boot the other operating system when the new diskette
	is in place.
    Once loaded, if you press RESET or otherwise reboot, the MODELA/III image will still be there and you can boot directly onto the NEWDOS or other Model III OS without having to swap diskettes again or pressing any other keys. If you cycle power, you will have to repeat the first procedure.
    Optional keys related to Model III-mode booting are [L], which means says to load the Model III image even if it doesn't appear to be needed, and [N], which says to NOT load the ROM-image even if it does appear to be needed.
    * Implied in that is if you make a NEWDOS diskette with a directory cylinder pointer in the boot sector that points to a cylinder that "looks" like a LDOS/LS-DOS diskette directory track, and it contains a LDOS/LS-DOS/TRSDOS-style directory entry that points to a cylinder/sector position containing the MODELA/III file data, *then* you could load from a non-TRSDOS/LDOS/LSDOS OS, and someone has done this, but you have to make a very strange looking disk layout to make it occur and it wastes a lot of space. This exercise is left to those with lots of spare time.

    For the more adventuresome ...Another Method


    Build a diskette with a boot sector that doesn't look like a Model III-mode boot sector. This means the ROM won't try to load MODELA/III at all, assuming it's a Model 4-mode diskette. Then when the boot sector is loaded and control is transferred to it, it can do anything it wants to. You could write a boot sector that knows where to load the MODELA/III file from on this alien disk format and load it yourself before loading the rest of the OS, or you could concatenate the BOOT/SYS or SYS0/SYS modules of the operating system onto the contents of a MODELA/III file, which loaded everything as though it was one big file. Typically the MODEL%/III contents needs to be loaded first, so that later stages of the boot process will have the old Model III ROM functions available for use, such as to print those boot-up screens.
    In theory, you could do the latter (build a blob file containing both MODELA/III and BOOT/SYS contents) and let the boot ROM do the work (ie load MODELA/III contents and BOOT/SYS that have been combined in one file), but it would be much easier to simply not let the boot ROM try to load a MODEL%/III file and take over things from there. You can't make the 4P-ROM know about any new disk formats, so the best choice is to not rely on it at all for that function.
    To decide if the MODELA/III file is needed, the 4P ROM scans sector 1 on the floppy diskette looking for the CD XX 00 (CALL 00XXH) instruction sequences and other clues. If it finds any, it knows the boot sector is expecting the Model III ROM image to be there, so the 4P-ROM loads the ROM image first before turning control over to the boot sector. Frequently, the only reference to the "A" ROM address range in the boot sector would be to display a message like "DISK ERROR", but that one hit was enough to make the determination automatic. I recall that during development back in 1983, Frank Durda IV tested several dozen alien diskette formats, including all the Kim Watt stuff, looking for signatures like this.

    Another solution, by Tony Domigan and Northern Bytes, Vol.5, #7, Page 14


    MODELA/III can be copied to LDOS 5.x and TRSDOS 1.3B diskettes so that they can Cold Start on the Model 4P. If, however, you wish to use NEWDOS/80 version 2.0 the only option is to load MODELA/Ill with 'pause' and then enter your NEWDOS disk - two operations not very convenient. Furthermore, the Model 4P hardware seems to check the boot sector (sector 1) in a way which excludes any DOS other than TRSDOS or LDOS.
    The method I have used relocates the NEWDOS directory to lump 36 i.e. track 20; the same track on which the LDOS directory resides,
    The FPDE for MODELA/III is created and the directory entry modified so that when the file is copied from the TRSDOS MODELA/Ill disk it will be copied to a true track. I have used track 30 as it is not allocated in a standard NEWDOS diskette,
    The ROM file is then modified on the NEWDOS diskette so that the bootstrap loader will select sector 0 to boot the diskette.
    Using Superzap the MODELA/III FPDE is again modified to read Track lEH or 30 decimal and the total granules changed to 09H. The normal boot sector (sector 1) is modified with 3 bytes located by the hardware in checking for a TRSDOS or LDOS disk.
    The diskette is now configured such that the hardware assumes it is an LDOS diskette with the ROM starting on track 30 decimal, Once loaded the ROM bootstrap boots NEWDOS from sector 0.
    1.Construct a new system diskette with a directory on lump 36 - e.g. 
               PDRIVE,0,1,DDSL=36,A
           COPY,0,1,00/00/00,CBF,FMT,NDP=NEWDOS4P,DPDN=1
    2.Boot the new system diskette,
    3.Create a file called MODELA/III - e.g. 
              CREATE MODELA/III:0
    4.Using Superzap, page through the directory, from relative sector 360, till the FPDE for MODELA/Ill is located, Modify Bytes 21-24 in FPDE i.e. 
              0000 FFFF to 3900 36DB
    5.From 'NEWDOS READY" copy MODELA/Ill from the TRSDOS 1.3B boot disk to the new NEWDOS disk - e.g. 
              COPY MODELA/III:1 :0 SPDN=4
    6.Using Superzap locate the MODELA/III FPDE and modify bytes 20-24 i.e. 
              Find 3900 360B Change to 3900 1E09
    7.Using Superzap 'DFS' modify MODELA/Ill at FRS 53 Relative Byte 39 i.e. 
              Find 3E01 D3F2 Change to 3E00 D3F2
    8.Using Superzap modify the first sector (360) of the directory (GAT). Change relative bytes 36H to 3BH inclusive to FF (i.e. lump(s) allocated),
    9.Modify Disk Relative Sector 1 at relative byte 0: Do a 'ZTFF' to zero the sector and modify: 
               Relative Byte 02 ==> 14
           Relative Byte 14 ==> 28
           Relative Byte SA ==> CD
    10.Now the easy part, RESET the 4P holding the 'P' and 'L' keys, If the ROM fails to load successfully then recheck the FPDE entry and the Sector 1 bytes. If the ROM loads successfully but NEWDOS fails, either partly or completely, then recheck the patch to MODELA/Ill (or perhaps you have accidentaliy written to the wrong part of the system!).

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             NewDos/80 System Files and Purposes - Art McAninch
    /sys0Essential
    /sys1Essential - Interrogates DOS commands
    /sys2Necessary - Creates files, opens FCBs, allocates file space, allocates FDEs, encodes passwords and loads user programs. Executor for RENAME and LOAD.
    /sys3Necessary. Closes FCBs, kills files, inserts/deletes entries. Executor for BLINK, BREAK, CLOCK, DEBUG, JKL, LCDVR, LC, VERIFY, and PURGE.
    /sys4Displays DOS ERROR messages
    /sys5DEBUG
    /sys6Executor for FORMAT, COPY, and APPEND.
    /sys7Executor for TIME, DATE, AUTO, ATTRIB, PROT, DUMP, HIMEM, and the first part of PURGE, SYSTEM, and PDRIVE.
    /sys8Executor for DIR and FREE.
    /sys9Executor for BASIC2, BOOT, CHAIN, CHNON, MDCOPY, PAUSE, and STMT.
    /sys10Executes BASIC statements GET and PUT.
    /sys11Executes BASIC direct statement RENUM.
    /sys12Executes BASIC direct command REF.
    /sys13Executes BASIC ERROR messages and the first part of RENUM.
    /sys14Executor for CLEAR, CREATE, ERROR, LIST, PRINT, and ROUTE.
    /sys15Executor for FORMS and SETCOM.
    /sys16Executor for most of PDRIVE.
    /sys17Executor for WRDIRP and most of SYSTEM.
    /sys18BASIC direct statement executor.
    /sys19Executor for BASIC statements LOAD, RUN, MERGE, SAVE, and CMD"F".
    /sys20Executor for a number of BASIC statements. Must be present if BASIC is active.
    /sys21Executor for CMD"O".

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             Modifying the AMPERSAND Command in NEWDOS/80 BASIC - Gil Spencer
    I never think in octal. It's hard enough to work in binary, hex, and decimal. It always seemed to me that the default for the '&' function should be hex, NOT octal. I finally dug out the source code (from Apparat's Disk BASIC) which I found in SYS20/SYS. My rewrite fits within the required extra space. Although a quantity of bytes are changed, this is because the code is "re-arranged" more than because it is "re-written".
    First, here is the Disk BASIC (&) routine found in Apparat's NEWDOS/80 version 2.0 - specifically SYS20/SYS, addresses 54C5H-5503H. If you are using SUPERZAP, address 54C5H is found at FRS 2, byte D1H and address 5503H is at FRS 3, byte 13H. Note that the four bytes at FRS 3, bytes 06H- 09H (which are 01 00 FA 54) are loader codes and must NOT be changed.
    54C5          00100         ORG     54C5H
54C5 D7       00110         RST     10H
54C6 4F       00120         LD      C,A
54C7 110000   00130         LD      DE,0000H
54CA 79       00140 Q54CAH  LD      A,C
54CB FE48     00150         CP      48H
54CD 2022     00160         JR      NZ,Q54F1H
54CF D7       00170         RST     10H
54D0 EB       00180         EX      DE,HL
54D1 D630     00190         SUB     30H
54D3 FE0A     00200         CP      0AH
54D5 3808     00210         JR      C,Q54DFH
54D7 D611     00220         SUB     11H
54D9 FE06     00230         CP      06H
54DB 3022     00240         JR      NC,Q54FFH
54DD C60A     00250         ADD     A,0AH
54DF 29       00260 Q54DFH  ADD     HL,HL
54E0 3807     00270         JR      C,Q54E9H
54E2 29       00280 Q54E2H  ADD     HL,HL
54E3 3804     00290         JR      C,Q54E9H
54E5 29       00300         ADD     HL,HL
54E6 3801     00310         JR      C,Q54E9H
54E8 29       00320         ADD     HL,HL
54E9 DAB207   00330 Q54E9H  JP      C,07B2H
54EC 85       00340         ADD     A,L
54ED 6F       00350         LD      L,A
54EE EB       00360         EX      DE,HL
54EF 18D9     00370         JR      Q54CAH
54F1 0E4F     00380 Q54F1H  LD      C,4FH
54F3 B9       00390         CP      C
54F4 2801     00400         JR      Z,Q54F7H
54F6 2B       00410         DEC     HL
54F7 D7       00420 Q54F7H  RST     10H
54F8 EB       00430         EX      DE,HL
54F9 D630     00440         SUB     30H
54FB FE08     00450         CP      08H
54FD 38E3     00460         JR      C,Q54E2H
54FF CD9A0A   00470 Q54FFH  CALL    0A9AH
5502 EB       00480         EX      DE,HL
5503 C9       00490         RET
    This is the REWRITE of the Disk BASIC ampersand (&) routine. Now the octal argument MUST be specified by '&O'. Hex argument MAY be specified by '&H'. No suffix (i.e. '&') now defaults to hex rather than octal.
    54C5          00100         ORG     54C5H
54C5 D7       00110         RST     10H
54C6 4F       00120         LD      C,A
54C7 110000   00130         LD      DE,0000H
54CA 79       00140 Q54CAH  LD      A,C
54CB FE4F     00150         CP      4FH
54CD 2828     00160         JR      Z,Q54F7H
54CF 0E48     00170         LD      C,48H
54D1 B9       00180         CP      C
54D2 2801     00190         JR      Z,Q54D5H
54D4 2B       00200         DEC     HL
54D5 D7       00210 Q54D5H  RST     10H
54D6 EB       00220         EX      DE,HL
54D7 D630     00230         SUB     30H
54D9 FE0A     00240         CP      0AH
54DB 3808     00250         JR      C,Q54E5H
54DD D611     00260         SUB     11H
54DF FE06     00270         CP      06H
54E1 301C     00280         JR      NC,Q54FFH
54E3 C60A     00290         ADD     A,0AH
54E5 29       00300 Q54E5H  ADD     HL,HL
54E6 3807     00310         JR      C,Q54EFH
54E8 29       00320 Q54E8H  ADD     HL,HL
54E9 3804     00330         JR      C,Q54EFH
54EB 29       00340         ADD     HL,HL
54EC 3801     00350         JR      C,Q54EFH
54EE 29       00360         ADD     HL,HL
54EF DAB207   00370 Q54EFH  JP      C,07B2H
54F2 85       00380         ADD     A,L
54F3 6F       00390         LD      L,A
54F4 EB       00400         EX      DE,HL
54F5 18D3     00410         JR      Q54CAH
54F7 D7       00420 Q54F7H  RST     10H
54F8 EB       00430         EX      DE,HL
54F9 D630     00440         SUB     30H
54FB FE08     00450         CP      08H
54FD 38E9     00460         JR      C,Q54E8H
54FF CD9A0A   00470 Q54FFH  CALL    0A9AH
5502 EB       00480         EX      DE,HL
5503 C9       00490         RET


             Initializing Hard Drives under Model IV DOS's - F. McCloy
    Following are instructions for initializing Radio Shack 12 & 35 Meg hard drives under TRSDOS 6.02.00 and LDOS 5.1.4 using TRS-80 models 4 &4p. These drives are not directly supported by Radio Shack for use with computers listed, and therefore, the "automatic formatting" utilities provided by RS will not give tou satisfactory results.
    PLEASE NOTE: The 35 Meg disk has 512 actual tracks, but you can use only 404 of them due to the limitation of the TRSHD6/DCT device driver. This limits useable space to about 80% of the drive's capacity. Partitioning the drive for both TRSDOS and LDOS will not solve the problem. (All of the space on the 12 Meg drive will be available to you.)
    Use the following procedure to initialize the 12 or 35 meg drive with TRSDOS 6.02.00. (A similar procedure can be used for LDOS using its utilities.):
    COMMAND

    ----------    		QUESTIONS

    ---------------    		ANSWER
    12 MEG
    ---------    		ANSWER
    35 MEG
    ------
    SYSTEM (DRIVE=6,DRIVER="TRSHD6") Number of heads:
    Tracks per surface
    Step Rate:
    # Heads/Partition
    Starting Head:    		 1
    6
    230
    .01
    1
    1    		 1
    8
    404
    .01
    1
    1
    TRSFORM6 :6 Disk pack name:
    Password:
    Manual Lockout:    		 HARDA
    PASSWORD
    N    		 HARDA
    PASSWORD
    N
    SYSTEM (DRIVE=1,DISABLE,DRIVER="TRSHD6") Drive Select Address:
    # Heads/partition:
    Starting head:    		 1
    1
    2    		 1
    2
    2
    TRSFORM6 :1 Disk pack name:
    Password:
    Manual Lockout:    		 HARDB
    PASSWORD
    N    		 HARDB
    PASSWORD
    N
    SYSTEM (DRIVE=2,DRIVER="TRSHD6") Drive Select Address:
    # Heads/partition:
    Starting head:    		 1
    1
    3    		 1
    2
    4
    TRSFORM6 :2 Disk pack name:
    Password:
    Manual Lockout:    		 HARDC
    PASSWORD
    N    		 HARDC
    PASSWORD
    N
    SYSTEM (DRIVE=3,DRIVER="TRSHD6") Drive Select Address:
    # Heads/partition:
    Starting head:    		 1
    1
    4    		 1
    1
    6
    TRSFORM6 :3 Disk pack name:
    Password:
    Manual Lockout:    		 HARDD
    PASSWORD
    N    		 HARDD
    PASSWORD
    N
    SYSTEM (DRIVE=4,DRIVER="TRSHD6") Drive Select Address:
    # Heads/partition:
    Starting head:    		 1
    1
    5    		 1
    1
    7
    TRSFORM6 :4 Disk pack name:
    Password:
    Manual Lockout:    		 HARDE
    PASSWORD
    N    		 HARDE
    PASSWORD
    N
    SYSTEM (DRIVE=5,DRIVER="TRSHD6") Drive Select Address:
    # Heads/partition:
    Starting head:    		 1
    1
    6    		 1
    1
    8
    TRSFORM6 :5 Disk pack name:
    Password:
    Manual Lockout:    		 HARDF
    PASSWORD
    N    		 HARDF
    PASSWORD
    N
    SYSTEM (DRIVE=7,DRIVER="FLOPPY") I/O ADDRESS: 2 2
    BACKUP :0 :6 (SYS,INV)
    SYSTEM (SYSTEM=6)
    SYSGEN (DRIVE=6)
    Your system is now set up as follows:
    LOGICAL
    DRIVE    		PHYSICAL
    DRIVE    		PHYSICAL
    DRIVE
    12 MEG35 MEG
    -----------------------------------------
    :0HD Head #1HD Head #1
    :1HD Head #2HD Head #2-3
    :2HD Head #3HD Head #4-5
    :3HD Head #4HD Head #6
    :4HD Head #5HD Head #7
    :5HD Head #6HD Head #8
    :6Floppy Drive #0Floppy Drive #0
    :7Floppy Drive #1Floppy Drive #1
    PLEASE NOTE: This procedure can provide guidelines for partitioning your 12 or 35 meg hard drive for use with both TRSDOS and LDOS.


             Passwords - Tim Mann/Frank Durda IV 
    Files        LDOS 5.1    LDOS 5.3.1    TRSDOS 6      LS-DOS 6.3.1
-----        --------    ----------    --------      ------------
basic/*      (unused)    basic         basic         basic
*/ov?                                  basic
lbasic/*     basic       (unused)      (unused)      (unused)
config/sys   ccc         ccc           ccc           ccc
*/sys        wolves      system        lsidos        system6
*/flt        gsltd       filter        filter        filter
*/dvr        gsltd       driver        driver        driver
*/dct        rrw3        driver        utility       driver or utility
*/cmd        rrw3        utility       utility       utility
*/hlp        (unused)    help          (unused)      help
back door    rs0lt0ff    rs0lt0ff      (none)        (set bit 7 of nflag$)
back door?   LDOSOKVS    LDOSOKVS                    LDOSOKVS

On 6.3.1H, for some reason, the password is .system6 instead of .lsidos.
    To disable password checking in LDOS IV v6.31, try 
    MEMORY (A="N",B=128)
    	Files		.Password
	-----		---------
	TRSHD*/DCT 	.P3UF  (this may be valid only for TRSHD4 series)

    Model I TRSDOS
Back-Door password on TRSDOS 2.3: NV36 and/or AF19
Master Password	"P3UF"

    C Code To Computer TRS-80 Passwords
written by Tim Mann 
http://www.research.digital.com/SRC/personal/Tim_Mann/


/* trspwhash
 * Usage:  trspwhash password	  // Hash a password
 *         trspwhash -u 0xhash    // Unhash a password to letters
 *         trspwhash -n 0xhash    // Unhash a password to letters and digits
 */
#include 

unsigned int
pwhash(unsigned char pw[8])
{
    unsigned char *p = &pw[7];
    unsigned int count = 8;
    unsigned int hl, t1, t2;

    hl = 0xffff;
    do {
	t1 = hl & 0x07;
	t2 = hl & 0xff;
	hl = (t1 << 13) ^ (t1 << 9) ^ (t1 << 2) ^
	     (t2 << 8) ^ (t2 << 4)  ^ (t2 >> 3) ^
             (hl >> 8) ^ (*p-- << 8);
    } while (--count);
    return hl;
}

void
usage()
{
    fprintf(stderr, "usage: trspwhash [-u | -n] arg\n");
    exit(1);
}

int
main(int argc, char **argv)
{
    unsigned int goal;
    unsigned char pw[17];
    int i;
    if (argc == 2) {
	strncpy(pw, argv[1], 8);
	pw[8] = '\0';
	strncat(pw, "        ");
	for (i = 0; i < 8; i++) {
	    if (islower(pw[i])) pw[i] = toupper(pw[i]);
	}
	printf("%04x\n", pwhash(pw));
    } else if (argc == 3 && strcmp(argv[1], "-u") == 0) {
	goal = strtoul(argv[2], (void*)0, 0);
	strcpy(pw, "        ");
	for (;;) {
	    if (pwhash(pw) == goal) printf("%s\n", pw);
	    i = 0;
	    for (;;) {
		switch (pw[i]) {
		  case ' ':
		    pw[i] = 'A';
		    break;
		  case 'Z':
		    pw[i] = 'A';
		    i++;
		    if (i == 8) exit(0);
		    continue;
		  default:
		    pw[i]++;
		    break;
		}
		break;
	    }
	}
    } else if (argc == 3 && strcmp(argv[1], "-n") == 0) {
	goal = strtoul(argv[2], (void*)0, 0);
	strcpy(pw, "        ");
	for (;;) {
	    if (pwhash(pw) == goal) printf("%s\n", pw);
	    i = 0;
	    for (;;) {
		switch (pw[i]) {
		  case ' ':
		    pw[i] = 'A';
		    break;
		  case 'Z':
		    pw[i] = '0';
		    break;
		  case '9':
		    pw[i] = 'A';
		    i++;
		    if (i == 8) exit(0);
		    continue;
		  default:
		    pw[i]++;
		    break;
		}
		break;
	    }
	}
    } else {
	usage();
    }
    return 0;
}


    Tom Price
    For those of you who have used the basic version of SUPERZAP from NEWDOS 2.1 to peek at the directory of the MODEL-III TRSDOS, you may have noticed that the password encode for a null (blank) password is EF5C rather than the old familiar 9642 from the MODEL-I. This is caused by Radio Shack using a slightly different algorithm to encode the passwords (they changed two bytes in the code), but the system works in much the same way. This article will explain three ways to get around the password system if you have a need to do so. The first two will require the above mentioned SUPERZAP, which is all we have until someone comes up with a version tailored to the MODEL-III's double density disk structure. the third method doesn't require any utility program at all and can be used by anyone.
    1.ZAPPING THE DIRECTORY - Use SUPERZAP to select track 1B, sector 4. This will bring you to the first sector of the directory. Then, use the ";" key to page through the directory until you find the programs you want. The first four bytes of the second line of each directory entry are the update and access password encodes respectively and, on an unprotected file, they will be EF5C EF5C. To remove the passwords on a protected file, just zap EF5C into the entry in place of Whatever you find there. just like the MODEL-I. Don't waste any time looking for the SYS Files. They aren't listed by name in the directory and don't have passwords anyway. I'll explain about that in a future article.
    2.DISABLING PASSWORD CHECKING - You can dispense with passwords altogether if you want to. Use SUPERZAP to bring up track 1A, sector 2. Then use the MOD function of SUPERZAP to change relative byte DE from 28 to 18. Press and type 'Y' to write the modified sector back to the diskette. From now on, all passwords will be ignored when accessing files if this diskette is used in drive #0.
    3.THE MASTER PASSWORD - If you don't have SUPERZAP or don't want to make any modifications to TRSDOS, you can access any file regardless of protection by using a master password to over-ride all other passwords. One such password is "NYXB". This acts as a master key to unlock any file and can be used if you have a diskette with a master password other than "PASSWORD".


             Model III Self-Booting Disk using NEWDOS/80 - by Leonard Yates (with help from Gary Bryce)
    Back in the August 1984 issue of SYDTRUG NEWS, Gary Bryce presented an article on creating self-booting disks using NEWDOS/80. The Model I mods worked well but,as he said at the end of the item, had not been verified on the Model III. Well, to get a Model III data disk to self-boot, you'll have to proceed as follow (I'll make this complete so you don't have to refer to the original article):
    1.FORMAT a data disk and copy the /CMD file to be made self-booting to it. If it's the only file on the disk (apart from BOOT/SYS and DIR/SYS), chances are it will have only one extent (as revealed by DIR dn1 A). If it has more than one extent, it's probably more than 32 granules long (Super Utility 3.2 is the longest program I've been able to self-boot).
    2.Using the DFS option of SUPERZAP, note the DRS of relative sector 0 of the /CMD file on the data disk. Next, using the DD option of SUPERZAP, and responding with the drive number and DRS noted above, record the TRS and TRK (in HEX) of the /CMD file on the data disk.
    3.Using the DFS option again, zap FRS 1 of BOOT/SYS (of the data disk) as follows:
    Byte 05 - TRS of /CMD file (will be 05H if it's the only USR file on the disk, and hence won't need to be changed). Byte 06 - TRK of /CMD file (will be 00H...etc.). Byte 3E - change from C8H to C9H.
    Note: If the /CMD file is the only USR file on the data disk, TRS will be 05H and TRK will be 00H. BOOT/SYS is normally set up to load SYS0/SYS which always occupies from sector 05 of track 0; for a nonsystem (data) disk, the first USR file will occupy this space. Note also that on NEWDOS/80 system and data disks for the Model III, sector 1 of BOOT/SYS is a duplicate of sector 0 (required for booting on the Model III) These changes are made to sector 1 only. Further, if your /CMD program is the only USR file on the data disk, the only zap needed is to byte 3E of FRS 1 of BOOT/SYS.
    4.Mount the self-booting data disk on drive 0 and press RESET. The disk will BOOT and the /CMD file will load and execute.


             Setting HIMEM from NEWDOS/80 v2.0 BASIC
    Regardless of what the documentation says, high memory cannot be set using a CMD "HIMEM,(decimal address)" command. The string storage area is still going to the top of 48k, even though you may have set HIMEM at 34000.
    The only way to set high memory from BASIC is to place a poke at the beginning of the program - before any string or variable definitions are made. To calculate the poke values needed, find the beginning address of the routine. Divide this number by 256. The most significant (MSB) byte of the address will be the integer value of your answer. Multiply the decimal portion of the answer by 256 to find the least significant byte (LSB). On a Model I or III: 
    POKE 16561,LSB : POKE 16562,MSB: CLEAR 50
    This will reset all pointers, and set memory to address calculated. The CLEAR 50 can be what ever value you need for your program. It is not necessary - and wasteful to clear more memory than needed.
    Note - String garbage collection will be done at fewer intervals when the maximum amount of memory has been cleared.


             System functions that can be accomplished in BASIC
    Functions to Read, Test, & Change bits: 
    DEF FNReadBit   (Address,Bit) = INT(PEEK(Address)/2^Bit)-2 * INT(PEEK(Address)/2^(Bit+1))
DEF FNResetBit  (Address,Bit) = PEEK(Address) - FNReadBit(Address,Bit) * 2^Bit
DEF FNSetBit    (Address,Bit) = PEEK(Address) + (1-FNReadBit(Address,Bit)) * 2^Bit
DEF FNToggleBit (Address,Bit) = FNResetBit(Address,Bit) + FNSetBit(Address,Bit) - peek(Address)

109 -- Bit 1==>  Type-Ahead
           Set = Enabled
         Reset = Disabled

116 -- Bit 5==>  Caps
           Set = Upper Only
         Reset = Upper/Lower

121 -- Bit 7==> Spooler
           Set = Despooling
         Reset = Paused

124 -- Bit 4==>  Break Key
           Set = Disabled
         Reset = Enabled

127 -- Bit 4==>  Clock Display
           Set = Display On
         Reset = Display Off

127 -- Bit 6==>  Cursor Control
           Set = Non-Blinking
         Reset = Blinking

For example to turn the clock display on from BASIC use the statement:
POKE 127,FNSetBit(127,4).
    Print string of number without a leading space:
    Call with A set to the number. 
         DEF FNST$(A)=RIGHT$(STR$(A),LEN(STR$(A))-1)
    Function to display the current DOS version:
       DEF FNVersion$="TRSDOS Version " + LEFT$(HEX$(PEEK(133)),1)+
       "." + RIGHT$(HEX$(PEEK(133)),1) + "."+HEX$(PEEK(59))
    Function to display the current date in 'Day, Mon ##, 19##' format:
          DEF FNDay$=MID$("SunMonTueWedThuFriSat",(((PEEK(55)AND 14)/2)-1)*3+1,3)+
          ", "+MID$("JanFebMarAprMayJunJulAugSepOctNovDec",(PEEK(53)-1)*3+1,3)+
          " "+RIGHT$(" "+FNST$(PEEK(52))+", 19"+FNST$(PEEK(51))
    Print appropiate article in front of a word:
    Call with A$ = to the word that you want the article in front of.
         DEF FNARTICLE$(A$)="A"+LEFT$("n",INSTR("AEIOUaeiou",LEFT$(A$,1)))+" "+A$
    Display a menu number in reverse video:
    Call with A = to menu number to display.
         DEF FNNUM$(A)="{"+CHR$(16)+FNST$(A)+CHR$(17)"} "
    Condense the TIME or DATE strings to 4 bytes:
    Call with A$ = to TIME$ or DATE$.
        DEF FNTIMEDATE$(A$)=MKS$(VAL(LEFT$(A$,2)+MID$(A$,4,2)+RIGHT$(A$,2)))
    Expand time or date string as condense above:
    Call with A$ = Condensed string -- B$ = seperator, '/' or ':'.
         DEF FNEXPAND$(A$,B$)=STRING$(6-LEN(FNST$(CVS(A$))),48) +
         LEFT$(FNST$(CVS(A$)),(LEN(FNST$(CVS(A$)))-4))+B$ +
         LEFT$(RIGHT$(FNST$(CVS(A$)),4),2)+B$ +
         RIGHT$(FNST$(CVS(A$)),2)
    Pad string on right or left to a specific length:
    Call with A$ = String -- A = maximum length to output
         DEF FNRSPC$(A$,A)=LEFT$(A$+SPACE$(A),A)
     DEF FNLSPC$(A$,A)=RIGHT$(SPACE$(A)+A$,A)


             Creating /CMD Files from LDOS LIB Commands
    There has been some confusion engendered about my suggestion on the LDOS board recently about the possibility of creating cmd files from individual library routines. I probably assumed a greater understanding of the system than was justified. Therefore, these remarks are an attempt to explain how you may create CMD files, the only purpose for which is to have more disk space available for data files or whatever.
    Using cmdfile you merely call for SYS6 or SYS7, depending where the routine you wish is located, and then give the overlay number when requested. these numbers may be found by reading a download of sys1 with the extended debugger. to make it easier i am listing them below: 
              APPEND    31                  ATTRIB    51
          AUTO      11                  BOOT      A9
          BUILD     33                  CLOCK     17
          COPY      32                  CREATE    13
          DATE      15                  DEBUG     14
          DEVICE    61                  DIR       21
          DO        91                  DUMP      71
          FILTER    66                  FREE      22
          KILL      18                  LIB       19
          LINK      62                  LIST      41
          LOAD      81                  MEMORY    1E
          PROT      52                  PURGE     72
          RENAME    53                  RESET     63
          ROUTE     64                  RUN       82
          SET       65                  SPOOL     A2
          SYSTEM    A1                  TIME      16
          TRACE     1A                  VERIFY    1B
          XFER      73
    I'll leave it to you to figure out to which sys file each of these belongs, reminding you that it is obligatorily SYS6 or SYS7. Let's assume you wish to create a CMD file of the copy command. Merely enter the number 32 when you are requested. it is not necessary to change addresses or transfer addresses, since you will be using the command file exactly as you would have used the library routine. Save the file with a different name since if you call 'copy' the parsing routine will load the routine from SYS6 and not your COPY/CMD file. In any case, you would only wish to create these cmd files to replace SYS6 and SYS7, reducing the overhead on your disk. This is especially useful for users with only disk drive. Since these routines, when changed into cmd files, will occupy a full gran of 5 sec- tors (6 on double density), it is clear that if you create too many such files, you will have defeated the purpose of elimin- ating the SYS6 & SYS7 files! as for names of the corresponding files, i should opt for names similar enough to the library commands to avoid confusion with yourself, ccopy for copy, ddir for dir, etc.
    Finally, for those who wish to better understand the principle employed with the library, i will explain how a routine is parsed and then loaded and run from its sys file. When you enter a command, it is parsed by SYS1, and a table with the names of all the LIB routines, each followed by the index no. shown above. Following that number is an 80 or a c0, which tells the system to look for the in SYS6 or SYS7. within the SYS6 or SYS7 file a search is made for the index number. this number is followed by the starting address of the routine once loaded and the relative sector number and relative byte where the routine is located within the sys file. The routine is loaded and executed.
    I hope these remarks will assist any interested users in better understanding both my idea of creating command files to save space, and of the library routines themselves.


             Changing The Minimum Cluster Size on Radio Shack Hard Drives - Adam Rubin - June 17, 1987
    This file explains how to modify your hard disk to get a granule size of 1 kilobyte. It assumes you're using a Radio Shack 5-meg Hard Disk (26-1130), TRSDOS 6.2 or LS-DOS 6.3, and the Radio Shack hard disk drivers that were included with TRSDOS 6.2.0, and that your hard disk is assigned as drives 0, 1, 2, and 3. Please read ALL of this file, and make sure you understand it, before you try to do anything!
    You've probably noticed that when you first set up your hard disk, space for files was allocated in units (granules) of 16 sectors, or 4K. As a result, any file stored takes up at least 4K of space. It's possible to change the DOS's description of the drive so that space is allocated in units of 1K, which means that there will be less wasted space when storing each file.
    On the other hand, reducing the granule size from 4K to 1K introduces other problems. For example, it's possible for a 12K file to be stored in 12 separate extents of 1K each, which would take considerably longer to access than, say, 3 extents of 4K each. Also, additional directory entries are needed when there are more than four extents, so there's more chance of filling up all the directory entries before the disk itself is full. Since each extent of a file can be no more than 32 granules, a minimum of one extent for each 32K of a file is necessary, and so any file longer than 4 times 32K, or 128K, will take up at least two directory entries. With these in mind, it's possible that part, or all, of your system would be better off with the granule size left at 4K.
    As mentioned above, this file assumes you're using the same setup that I am. If your system is different, it may be possible to adapt the method described here, but you'd have to determine that on your own.
    The procedure described below will alter the Drive Control Table (DCT) for the chosen drive(s) to indicate 4 sectors per granule, 8 granules per cylinder. (Remember that 8 is the maximum number of granules allowed per cylinder.) Since, as mentioned above, files may require more extents, and possibly additional directory entries, it's necessary to reformat the drive.
    After you've modified your hard disk, you don't have to repeat this whole procedure to reformat one or more of the drives. Boot with the boot diskette created by the steps below (don't forget SYSTEM (SYSTEM=4) if you're reformatting :0), backup the files, use TRSFORM6 to reformat the drive, list BOOT/SYS as explained below (again, this is essential!), DATECONV if necessary, and restore your files.
    You can use the procedure below to change one, several, or all of the drives on your HD to 1K granules. (Any changes to the HD won't affect floppy disks; they'll still be formatted as six sectors (1.5K) per granule.) If, sometime later, you'd like to change an additional drive to use 1K granules, just repeat the procedure described below for that drive. If you'd like to change a drive back to 4K granules, the same procedure also applies, but use the unmodified TRSHD6/DCT instead of TRSHD6A.
    If you're using a 4P and have installed some sort of HD boot scheme, reread its documentation CAREFULLY before doing anything! It may be necessary to re-install the boot routine after modifying the hard disk.
    If any of the drives you're changing are also used by LDOS 5.x, the procedure gets somewhat trickier. My suggestion for that is to modify the CONFIG/SYS.CCC file on your LDOS hard disk boot diskette, by changing DCT+8 for the affected drives from 2F to E3 to reflect the change.
    The method in this file appears to work as described. However, I do not accept responsibility for any consequences of using the information in this file, and anything you do must be done at your own risk.
    Here's how to modify your hard disk for 1K granules:
    1) Make a backup of your current hard disk boot diskette. This will become your new boot diskette once you've finished this whole procedure. Make sure it has TRSHD6/DCT, TRSFORM6/CMD, and, if you're using 6.3, DATECONV/CMD.
    2) Create a patch file called TRSHD6A/FIX with these four lines:
    D02,EE=CD 56 33
F02,EE=3D 0F 0F
D01,66=CB 3A CB 3A 87 87 3D 0F 0F C9
F01,66=00 00 00 00 00 00 00 00 00 00
    then
    RENAME TRSHD6/DCT.DRIVER:f TO TRSHD6A/DCT
    (where "f" is the drive containing the backup of the boot diskette), and
    PATCH TRSHD6A/DCT:f USING TRSHD6A
    to patch it with the patch file.
    3) Reboot your system with this backup of the boot diskette.
    4) Type
    SYSTEM (SYSTEM=4)
    to make the floppy your system drive while you change the hard disk. During all of step 5, therefore, you'll have to refer to what's usually :0 as :4.
    5) For each drive to change (which I'll call drive "d" here),
    A)BACKUP *all* the files on that drive.
    B)
    SYSTEM (DRIVE=d,DISABLE,DRIVER="TRSHD6A")
    and answer the prompts. (Make sure you're using TRSHD6A, not TRSHD6.) With the setup I have, the drive select address is 1 for all drives, each drive uses one head, and the starting head number is the logical drive number plus one. The starting head number for what's normally drive :0 (which is currently :4) is 1.
    C)
    TRSFORM6 :d
    and answer the prompts. Disk name is up to you, and so is the disk master password. Unless you'd previously specified something else, the disk's current master password is probably PASSWORD. For "Manual lockout of tracks?", answer N. The appropriate portion of your hard drive will be reformatted, which takes a few minutes.
    D)
    LIST BOOT/SYS.LSIDOS:d (HEX)
    to allocate the remainder of the space necessary for BOOT/SYS. This is ESSENTIAL, since TRSFORM6 assumes an unmodified driver, and you've thrown its calculations off by modifying TRSHD6/DCT.
    E)If you're using 6.3,
    DATECONV :d
    F)Restore your files back onto the hard disk.
    G)Repeat steps 5A-5F for each drive to be changed.
    6) Type
    SYSTEM (SYSTEM=4)
    to make the hard disk your system drive again.
    7) Type
    SYSGEN (DRIVE=4)
    to write the updated configuration file to the floppy disk.
    8) The floppy disk is now your new boot diskette. Label it, and make several backups of it. Do NOT use your old boot diskette any more, as it won't work.


             Guided Tour Through The Model III TRSDOS Directory
    This article will describe and explain the important features of the Model-III TRSDOS directory. You'll see that it is quite similar in most respects to the Model-I directory except for the way in which the DOS SYSTEM files are handled.
    As in the Model-I, the directory is located on Track #17 (11H), and occupies the entire track. Because of the Model-III's double density format, this amounts to 18, 256 byte sectors. The first sector (#0) contains the Granule Allocation Table (GAT), the diskette Master Password encode, the diskette name and any AUTO command which may be active. Sector #1 contains the Hash Index Table (HIT) and the information by which TRSDOS is able to locate the SYSTEM files. The remaining sixteen sectors of the directory track contain the directory entries for the diskettes user files, five entries per sector.
    Let's take a look at Track #17 in detail:
    1. Sector #0 (the GAT sector) - The first 40 bytes (00H to 27H) make up the GAT and represent Tracks 0 to 39 on the diskette. Each byte is a "bit map" of the allocated granules in the corresponding track. Bits 0 through 5 represent the 6 granules of the track and bits 6 and 7 are not used (always 0). Thus, a fully allocated track would appear as a '3F' in the GAT. In binary this would be 00111111. If a byte is '25', a binary 00100101, it means that the first, third and sixth granules are allocated.

    Bytes CEH and CFH of Sector #0 are the encoded Master Password for the diskette. This is normally D38F for "PASSWORD". Bytes D0H - DFH are the diskette's name in ASCII and the creation date in MM/DD/YY format. Bytes E0H - FFH are used to store any AUTO command which may have been set up for the diskette. If byte E0H is a '0D' (carriage return), no AUTO command is in effect.
    2. Sector #1 (the HIT sector) - The first 80 bytes (00H to 4FH) make up the Hash Index Table (HIT). Each non-zero byte is the hash code for an active file in the directory, and its position in the HIT indicates in which sector and where in the sector the directory entry is located. For example, on a standard Radio Shack TRSDOS diskette, the first two bytes are 'F0' and 'F4', which are the hash codes for BASIC/CMD and CONVERT/CMD. A glance at Sector #2 will confirm that these files are the first two entries in that sector. The Model-III uses the same algorithm as the Model-I for computing hash codes.

    Bytes E0H - FDH are used to store the size and location of the TRSDOS SYSTEM files. There are 15 pairs of bytes and each pair represent one of the SYS files. The first byte of the pair contains the granule offset and the size of the file in granules. The second byte of the pair is the number of the track in HEX where the file starts. To see how this works, let's take a look at bytes E4H-E5H which are '4210'. The '42' is 01000010 in binary notation. Because the byte has two pieces of information embedded in it, we'll write it as 010 00010. The '00010' is the granule count for the file, which is TWO. The '010' is the granule offset from the start of the track which is also TWO. Remember that a granule is three sectors in the Model-III. The second byte of the pair is '10' which means that the file starts on Track #16 (10H). Putting it all together, we see that the file starts on Track #16 (10H), beginning on Sector #6 (offset of TWO granules) and occupies TWO granules or six sectors. This particular file, by the way, is very similar to SYS2/SYS on the Model-I. The fifteen pairs of bytes in this area represent the TRSDOS resident module and fourteen overlay modules making up the entire DOS. The sixteenth pair is presently 'FFFF' and is not in use, no doubt being reserved for a future overlay, like a spooler (just a guess). Since the user never calls the DOS modules directly, they need not have names and the information in these byte pairs is all that TRSDOS needs in order to locate them when program execution calls for them.
    3. Sectors #2 through #17 (Named directory entries) - There is room for five, three line (48 byte) directory entries on each of these sixteen sectors. This gives a total capacity of 80 named files. The sixteenth line on each sector is not used, so Radio Shack placed a '(c) 1980 Tandy' on it as a filler. Let's look at the first entry in Sector #2 to see how it is constructed. This is the entry for BASIC/CMD and it looks like this: 
    5E08 5000 0042 4153 4943 2020 2043 4D44
0000 EF5C 1200 0E06 FFFF FFFF FFFF FFFF
FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF
    The first byte, '5E', contains the file type, its visibility and protection level. In binary this is 01011110 and we'll write it as 0 1 0 1 1 110 to make it easier to break it down. Bits 0-2 are the protection level. In this case, it is 6 (EXECute only). Bit 3 is the visibility bit. A '1' means that the file is invisible, as in this case. If bit 4 is a '1', the file is an active file and has a corresponding HIT entry. Bit 5 is usually '0', but if it should be a '1', it means that the file has a backup limitation. Radio Shack has said in a newsletter that certain programs like Scripsit and VisiCalc will be limited to two backup copies. Whether this can circumvented by setting bit 5 to '0', I have no idea. Might be worth trying. If bit 6 is a '1', the file is a SYSTEM file. If it is a '0', it is a USER file. If the Model-III TRSDOS has been set up using the same methods as the Model-I, bit 7 will be '0' for a Primary directory entry and will be a '1' for an EXTENDED directory entry. I don't know if this is true for the Model-III. If not, a file will be limited to 12 extents. In any case, bit 7 is '0' for all my files.

    The second and third bytes are simply the file creation month and year in HEX, in this case '08 50', meaning 08/80. The fourth byte shows the location of the EOF byte in the file's final sector. The fifth byte is the Logical Record Length of the file (00 means 256 bytes). The sixth through the sixteenth bytes are the file name in ASCII, in this example, BASIC CMD.

    Bytes 17-18 and 19-20 are the UPDATE and ACCESS password encodes, respectively. For this file, we see '0000 EF5C'. 'EF5C' is the code for NO password, so BASIC/CMD has an UPDATE password assigned but no access password.

    Bytes 21-22 indicate the total number of sectors in the file in LSB-MSB format. So BASIC/CMD has 18 (12H) sectors.

    The next 26 byte are arranged in pairs and are used for the file EXTENTS. 'FFFF' indicates no further extents. The first byte is the number in HEX where the extent begins. In our example, this is '0E' meaning Track #14. The second byte of the pair contains the file's granule count and offset, encoded in exactly the same way as for the TRSDOS system modules. For BASIC/CMD, this byte is '06' which is 000 00110 in binary notation. Thus BASIC/CMD occupies 6 granules and starts at the beginning of the track (no offset).


             Formatting A Double-Sided Diskette Under TRSDOS 6.x / LDOS 5.1.x and 6.x - Jeffrey Brenton
    TRSDOS 6.x is an advanced version of the LDOS operating system designed for use on all-RAM computers using the Z80 processor. TRSDOS 6.x supports a variety of disk types, although only a few are documented in the official Tandy documentation. Drive types supported include:
         5" mini-floppy in single- and double-density, single- and double-sided, with cylinder counts of up to 96.
         8" floppy in single- and double-density, single- and double-sided and 77 cylinders.
         Hard (or "rigid") drives of various sizes, cylinder and head counts.
    All that is required to take advantage of these disk types is the hardware itself and the proper "driver" to control it. Full support for all 5" drive types is included with the basic TRSDOS system, but only 40-track, single sided operation is documented.
    To use a double-sided drive under TRSDOS, all that is necessary (apart from the drive itself) is to format the diskette for two sides. In non-Tandy versions of LDOS 6.x, the FORMAT utility will prompt the user for the number of sides to format, however Tandy asked that this prompt be bypassed due to the fact that they do not sell a double-sided drive for the model 4. You can still format for two sides, though. All that is necessary is to specify "SIDES=2" in the parameter section of your command line.
    Thus: 
    FORMAT :1 (cyl=80,sides=2)

    will format drive 1 for 80 tracks and 2 sides. FORMAT will ask for disk name and master password.
    If you wish to then use this double-sided diskette as your "boot" diskette, you *must* be sure that SYS0/SYS begins with the first sector of a cylinder. The only way to guarantee this is to back it up to the blank diskette *first*. To do this, use the command: 
    BACKUP SYS0/SYS:0 :1 (S)
    Follow that with: 
    BACKUP SYS/SYS:0 :1 (NEW)
    to get the rest of the system files transfered properly. You can backup any other files that you want (or need) to the diskette. Remember! Unless you backup the system files to a blank diskette *before* using it for anything else, LDOS/TRSDOS 6.x will assume that the diskette is a data diskette and will refuse to install the system files. If you inadvertantly use COPY before installing the system files, you will have to re-format the diskette.












             Addresses of TRSDOS 6.2 Routines - Colin Dunn
    Ah, the glory of rebelling against the untrue statements in the TRSDOS 6.2 manual. The manual says that you should not call any DOS routines without using the SVC's (LD A,x and RST 28H). Why not escape this waste of source and use a CALL xxxxH instruction? It is also faster because DOS won't need to look up the SVC's in the table. The Shack would scream if us programmers were making TRSDOS 6.2 run faster than a snail...but is it worth the pain of the scream to save the ENDLESS pain of RST 28H instructions? Also, now that we have the addresses to all the SVC's, let's get the disassemblers into action and disassemble this DOS 6.2 thing and disseminate the good new undocumented addresses. One catch is that this is not guaranteed to work on DOSes other than 6.20. DO NOT USE TRSDOS 6.21 has it has a bug that erases parts of files on the disk! It just totally ignores the granule allocation table! Well, I think I've said enough of this crap, so let's get to business. The rules for calling the DOS routines are the same as for the SVC's, except instead of LD A,x and RST 28H you CALL xxxxH. The registers must be the same on entry. The exit conditions remain the same. It is still advisable to PUSH AF when calling DOS routines because the routines may internally use AF. For an explanation of the routines (DOS names have been used in this file), see your copy of the Model 4 TRSDOS manual.
    @IPL: 1BF2H
    @KEY: 0628H
    @DSP: 0642H
    @GET: 0638H
    @PUT: 0645H
    @CTL: 0623H
    @PRT: 063DH
    @WHERE: 1979H
    @KBD: 0635H
    @KEYIN: 0585H
    @DSPLY: 052DH
    @LOGER: 0503H
    @LOGOT: 0500H
    @MSG: 0530H
    @PRINT: 0528H
    @VDCTL: 0B99H
    @PAUSE: 0382H
    @PARAM: 1987H
    @DATE: 07A8H
    @TIME: 078DH
    @CHNIO: 0689H
    @ABORT: 1B08H
    @EXIT: 1B0BH
    SVC #23 (012EH in the table) is undefined. It points to 1AF4H (displays SYSTEM ERROR 2BH)
    @CMNDI: 197EH
    @CMNDR: 197BH
    @ERROR: 1B0FH
    @DEBUG: 19A0H
    @CKTSK: 1CF5H
    @ADTSK: 1CDAH
    @RMTSK: 1CD7H
    @RPTSK: 1CEBH
    @KLTSK: 1CD0H
    @CKDRV: 1993H
    @DODIR: 19AFH
    @RAMDIR: 19ACH
    SVC #36-39 (0148H-014FH in the table) are undefined. These locations contain 1AF4H (a call that returns SYSTEM ERROR 2BH, SVC PARAMETER ERROR)
    @DCSTAT: 19B5H
    @SLCT: 19BCH
    @DCINIT: 19C0H
    @DCRES: 19C4H
    @RSTOR: 19C8H
    @STEPI: 19CCH
    @SEEK: 19D0H
    @RSLCT: 19D4H
    @RDHDR: 19D8H
    @RDSEC: 19F4H
    @VRSEC: 19DCH
    @RDTRK: 19E0H
    @HDFMT: 19E4H
    @WRSEC: 19E8H
    @WRSSC: 19ECH
    @WRTRK: 19F0H
    @RENAM: 1996H
    @REMOV: 19A6H
    @INIT: 198DH
    @OPEN: 198AH
    @CLOSE: 1999H
    @BKSP: 1486H
    @CKEOF: 158FH
    @LOC: 14B3H
    @LOF: 14DEH
    @PEOF: 14A2H
    @POSN: 1434H
    @READ: 1513H
    @REW: 149BH
    @RREAD: 1473H
    @RWRIT: 13ADH
    @SEEKSC: 1421H
    @SKIP: 1430H
    @VER: 1560H
    @WEOF: 14ECH
    @WRITE: 1531H
    @LOAD: 1B38H
    @RUN: 1B1DH
    @FSPEC: 1981H
    @FEXT: 1984H
    @FNAME: 199CH
    @GTDCT: 1A1EH
    @GTDCB: 1990H
    @GTMOD: 19B2H
    SVC #84 RETURNS SYS ERROR 2B - LOCATION IN TABLE IS 01A8H
    @RDSSC: 18D8H
    SVC #86 IS A MYSTERY SVC NOT LISTED IN THE MANUAL. IT CALLS A ROUTINE AT 1874 HEX THAT I CAN'T FIGURE OUT. ANYONE KNOW WHAT THIS ONE'S FOR?
    @DIRRD: 18BBH
    @DIRWR: 1803H
    SVC #89 IS ANOTHER MYSTERY THAT JUMPS TO ADDRESS 1875 HEX.
    @MUL8: 190AH
    @DIV16: 06C9H
    SVC #92 RETURNS SYS ERROR 2B - LOCATION IN TABLE IS 01B8H
    @DIV8: 1927H
    @DIV16: 06E3H
    SVC #95 RETURNS SYS ERROR 2B - LOCATION IN TABLE IS 01BEH
    @DECHEX: 03E1H
    @HEXDEC: 06F6H
    @HEX8: 07C2H
    @HEX16: 07BDH
    @HIGH$: 1948H
    @FLAGS: 196AH
    @BANK: 0877H
    @BREAK: 196FH
    @SOUND: 0392H
    @CLS: 0545H
    @CKBRKC: 0553H
    SVC'S #107-#127 are free for you to use. SVC #107 is found in location 01D6H. Each one after that is found two bytes later. You can use the following formula to calculate exact locations (under DOS 6.20):
    LOC=0100H+SVC*2
    Where SVC is the number of the SVC you wish to program. You CAN program OVER the DOS SVC's, but should you use this practice, use the @IPL SVC (#000, address 1BF2H) to exit your program. If you don't wish to reboot, store the original SVC table in a buffer as follows:
    LD HL,0100H
LD DE,BUFFER
LD BC,0100H
LDIR
    The SVC table is 256 bytes long and is ALWAYS found on a page boundary (even multiples of 100 hex). Should the SVC table get moved, you can get its starting address by using this code...
    LD A,101
RST 28H
LD A,(IY+26)
LD H,A
LD L,0
; NOW HL HAS THE ADDRESS - MSB IS IN H, LSB ALWAYS ZERO.
    NOTE: If the SVC table got moved, the addresses provided above would be wrong.


             Trading Files Between LDOS6.2 and NewDOS/80 v2.0 - Chris Anderson
    One of the things I quickly discovered as I began working with my new Model 4P was that there was going to be a need to move data back and forth between my old NEWDOS disks and LDOS6 disks. The following procedure is very straightforward, and will work without hassle for those important data files.
    Note: The following procedure requires at least two drives!
    NEWDOS80 V2 to LDOS6.2
    1)Boot under LDOS6.2.
    2)Format a disk SSSD, 35 tracks. You MUST use single side, single density and 35 tracks, regardless of the type of drive you are actually using!
    3)Boot NEWDOS80 V2. (Note, if you are a 4P owner, and are having problems booting NEWDOS, see the info file on this topic)
    4)Set the PDRIVE for the drive where the LDOS disk resides to TI=A,TD=A,TC=35,SPT=10,GPL=2,DDSL=17,DDGA=2.
    5)Use the normal NEWDOS Copy command to copy the file from your NEWDOS80 disk to the LDOS disk.
    6)Reboot the system using LDOS6.2.
    7)Use the RESET command or TSK/CMD if you have several copied files) to CLOSE each of the copied files. NEWDOS is not familiar with the open/closed status, and will leave each file open when copying it over to LDOS.
    That's all there is to the job in that direction. Going the other way is just as easy.
    LDOS6.2 to NEWDOS80 V2
    Perform the steps above in the following order:
    1)Boot in 6.2
    2)Format as noted above. Then, copy files as desired to the newly formatted disk while still in LDOS.
    3)Boot NEWDOS.
    4)Set PDRIVE as noted above.
    5)Use normal NEWDOS copy command to move files from the LDOS disk to the NEWDOS disk.
    Provided you have a Model 4 (and not a 4P) you may also find that it is fairly fast to use Multidos for this sort of thing.


             NewDOS/80 v2.0 Other-DOS PDRIVE Settings - Phill Walsh - March 17, 1985
    I have recently had to 'tidy up' a friends Model III discs which brought me to a documentation study of the PDRIVE functions of NEWDOS80 as I found myself faced with the problem of compatibility between TRSDOS, DOSPLUS, LDOS and (my favourite) NEWDOS80 V.2. This document examines SOME of the methods NEWDOS80 V.2 uses to overcome these problems with its library command 'PDRIVE'.
    The reason we can't read DOSPLUS and LDOS double density discs is that they have strayed from the norm. The 'norm' in the computer industry appears to be whatever the programmer/designer decides that it will be at the time of their current project. It would take approximately 5K of program to allow NEWDOS80 to read their type of double density directory. Whilst either one will read between a double or single density Model I or Model III of their own type, they do not have the ability to read one of the others. Therefore if you have some DOSPLUS or LDOS files and wish them on NEWDOS80, copy them to single density discs and then set up the PDRIVE table as example #1 in the following table. This will allow NEWDOS80 to read and copy them onto a NEWDOS80 system or formatted data disc. One thing that you may not be aware of at first is that you are not limited to two letters in the 'TI' spec of PDRIVE. The manual states:
    "TI = etc., Where TI consists of one or more alphabetic letter flags chosen from, etc."
    This means one or MORE alphabetic letter flags can be used in the 'TI' spec. Even though all the examples given therein consist of one or two - you can have three if so required. Example 6 in the manual displays:
    PDRIVE,dn1,dn2,TI=AK,TD=E,TC=39,SPT=18,TSR=3,GPL=2,DDSL=17, DDGA=2
    This specification is for the Model III for 13.3cm disc, 40 tracks, double density, single-sided disc that has track zero formatted in single density. Now by just altering the TI=AK to TI=AL, you have the same specification except that you can read that same 40 track disc in an 80 track drive.
    Some examples of PDRIVE tables:
    Example #1.
           PDRIVE,0,9,TI=A,TD=A,TC=40,SPT=10,TSR=3,GPL=2,DDSL=17,DDGA=2
    This spec allows you to read LDOS single density discs as is, and DOSPLUS single density discs (after WRDIRP) that are 40 tracks.
    Example #2.
           PDRIVE,0,8,TI=AM,TD=E,TC=40,SPT=18,TSR=3,GPL=6,DDSL=17,DDGA=2
    This spec will allow you to copy any known file from a Model III TRSDOS disc. You still will not be able to read the directory, as the TRSDOS directory is not compatible with any other marketed system. You can read the TRSDOS directory in one of two manners:
    Boot up the TRSDOS disc and call up the directory, or better still, call up 'SUPERZAP' go into 'DD' that contains the TRSDOS disc and (display drive relative sector 306), you can even MOD sectors. This will display the directory and other sectors whilst in NEWDOS80 using the above PDRIVE setup.
    Example #3.
           PDRIVE,0,7,TI=AK,TD=E,TC=39,SPT=18,TSR=3,GPL=2,DDSL=17,DDGA=2
    This spec tells your Model III that you are looking at a Model I NEWDOS80 disc that is double density with track zero in single density.
    Example #4.
           PDRIVE,0,6,TI=AL,TD=E,TC=40,SPT=18,TRS=3,GPL=2,DDSL=17,DDGA=2
    This is the standard Model III setup except that you can read the 40 track disc in an 80 track drive.
    Example #5.
           PDRIVE,0,5,TI=AL,TD=A,TC=40,SPT=10,TSR=3,GPL=2,DDSL=17,DDGA=2
    This spec is the same as example #1 (LDOS read) except that you can read it in an 80 track drive.
    Example #6.
           PDRIVE,0,4,TI=ALM,TD=E,TC=40,SPT=18,TSR=3,GPL=6,DDSL=17,DDGA= 2
    This one is the same as example #2 (TRSDOS III) except that the disk is read in an 80 track drive.
    Example #7.
           PDRIVE,0,3,TI=A,TD=E,TC=80,SPT=18,TSR=3,GPL=2,DDSL=17,DDGA=2
    This is the standard setup for an 80 track drive on the Model III.
    Example #8.
           PDRIVE,0,2,TI=A,TD=E,TC=40,SPT=18,TSR=3,GPL=2,DDSL=17,DDGA=2
    This is the 40 track standard setup.
    One small pointer. If you have two drives on your system, set up the 'SYSTEM' options command of 'AL=2'. This will give you use of the other seven PDRIVE tables as a storage area for the tables that you are likely to be using at different times. If you have three drives, set 'AL=3". When you need a different drive option, you only type "PDRIVE,0 1=7" and presto, you are ready. By resetting the 'AL' function, you not only gain the extra storage space, but your system need not go looking for a file on a drive that doesn't exist. This actually increases your disk I/O time - sure not by much, but every nanosecond counts.


             Configuring LDOS like NEWDOS/80 - Rowan Evans
    At last we have some questions to answer on LDOS!! The first one comes from a Newdos 80 user, who wants to know "How to configure LDOS, and what all the /DVR and /FLT files do", and the second from a TRSDOS 6.x user who wants to access the system status flags from within a BASIC program.
    Configuring LDOS.
    The first thing that should be done to configure LDOS for the system you use is to list the options that your system needs- e.g. Double Density, Printer Driver, etc. The easiest way to do this is to list your current Newdos configuration, or if you don't use Newdos, your hardware and its requirements.
    1.Using an existing Newdos system configuration list.
    I have listed the Newdos configuration options below and their LDOS counterparts. Items marked + cannot be SYSGENed under LDOS. Items marked * can be done if a driver or filter is written.
    SYSTEMLDOS
    +AAPassword enable - LDOS passwords are always enabled, with the option of a "Global" password to allow access to ANY file (password is "RS0LT0FF").
    ABRun only - this is possible under LDOS by forcing a non-breakable AUTO with the SYSTEM option BREAK=N.
    ACDebounce routine On/Off - LDOS does its debounce through the KI/DVR, so by disabling it, debounce is disabled.
    AD"JKL" screen print On/Off - This is also a function of the KI/DVR.
    AE"123" invokes debug -press instead once debug is activated.
    AF"DFG" invokes miniDOS -install LDOS' MINIDOS/FLT then by pressing and then another key, several minidos functions are available -
    <CLEAR> & "C" - Clock on/off.
    <CLEAR> & "D" - Enter Debug.
    <CLEAR> & "F" - Free space on all active drives.
    <CLEAR> & "K" - Kill a file.
    <CLEAR> & "P" - Send a character to the printer.
    <CLEAR> & "Q" - Directory of selected disk drive.
    <CLEAR> & "R" - Repeat last DOS command.
    <CLEAR> & "T" - Send form feed to printer.
    AG Break key status - use LDOS' command SYSTEM (BREAK=ON/OFF).
    AHNot defined in Newdos 80 version 2.