TRS-80 DOS – DOSPLUS

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General

• Background and Screen Shots
• Matthew Reed’s DOSPLUS Page (Other Site)

Zaps

• Forcing VERIFY in DOSPLUS v3.4
• Zap – Disabling Passwords in DOSPLUS v3.4

Manual

• DOSPLUS 3.5 Background and Features
• DOSPLUS 3.5 Conventions
• DOSPLUS 3.5 Library Command Reference
• DOSPLUS 3.5 Drivers and Filters Reference
• DOSPLUS 3.5 Job Control Language Reference
• DOSPLUS 3.5 Disk BASIC Extensions
• DOSPLUS 3.5 Disk BASIC Shorthand
• DOSPLUS 3.5 Disk BASIC Error Messages
• DOSPLUS 3.5 Disk BASIC Error Codes

Background of DOSPLUS 3.5

DOSPLUS 3.5 is a Disk Operating System for the Model I and Model III TRS-80 made by Micro Systems Software Inc. of Boca Raton, Florida. It was released in 1983 for the Model I and Model III TRS-80 at a suggested retail price of $149.95.

Although not an exhaustive list by any means, the following were some of the features which set DOSPLUS 3.5 apart from TRSDOS, and in some cases, apart from other DOS’s:

Devices, Files, and Drives Are Treated The Same

One of DOSPLUS 3.5’s strength, particularly over TRSDOS, was that it allowed the user to treat devices as files. You could switch, kill, reassign, and reconfigure input/output devices at will. As far as DOSPLUS 3.5 was concerned, you could manipulate the Keyboard (KI), Display (DO), Printer (PR), RS-232 (RS), and two user-defined hardware devices (U1 and U2), as well as 8 disk drive types. The devices were operated by character (one byte at a time), while the drives were operated by files (one file at a time). However, character-oriented and file-oriented devices could be made to perform as each other, so you really could interchange files, drives, and devices (within reason, of course). These relationships were established by ASSIGN, JOIN, FORCE, and RESET.

Join connects the specified devices to receive the same byte simultaneously or to link two input devices so that one unit supplies data for the other. You can also use Join to join the device to a disk file. For example, you can use the command: JOIN (FROM) @DO (TO) @PR to provide a printout of all items displayed to the video. The command Join alone provides a listing of the current status of the character-oriented devices and their driver address.

Force diverts output from the previously assigned device and sends it to the new device. This allows the redirection of input and/or output paths for the system’s devices. For example, the command FORCE (FROM) @PR (TO) fdespec reroutes the output from the printer to the filespec disk file. Force without any I/O field provides a listing of the current status of the character-oriented devices and their driver address.

Reset restores a device or disk drive to the previously assigned driver. This disolves any Joins or Forces in effect for the specified device and restores the default or initial driver to service. Reset without any other fields performs a global reset of all devices.

Assign installs drivers for a device or drive. This command lets you install a nonstandard driver for any device or drive in the system. The driver is a program that controls the input/output from a specific device or drive, such as hard disk drives. Once you install the driver program on a device by using the Assign command, you can assign the same driver to other devices by using the Assign command without allocating more memory. Assign requires that the driver program be in a loader format machine executable tile. The Assign command loads this driver into memory and the program executes the routine.

Filters

DOSPLUS 3.5 also supported filters – customized tables which would convert an input file to an output file, using the translations in the filter.

By combining the device based driver model with filters, otherwise complex tasks were made fairly routine. Examples, keyboard debounce, keyboard repeat delays, macro keys, character filtering were some examples using the Keyboard. Similarly, special cursors and lowercase were simple work for the Display. Of course, both serial and printer benefited from spooling, automatic pagination, and indenting. Pretty cool stuff, but the most stunning is that you could route a device to a file, essentially making the file a container which acted as a disk drive (which would have been a precursor of directories on a hard drive).

Wildcard Support

In addition, DOSPLUS 3.5 also supported wildcards for filenames. For example, KILL :0 USING ! would kill all visible files on :0 (and is the same as KILL !:0)

CONFIG

Similar to LDOS’s CONFIG, and NewDos/80’s PDRIVE and SYSTEM, DOSPLUS 3.5 allowed you to configure the attributes of drives, including allowing the use of Hard Drives.

LOAD

The LOAD command could be used to load “core image files” which different from CMD files in that they have no header, and represent the format at which the file would appear in memory.

System Customizations

DOSPLUS 3.5 could be customized so that specific system drivers were loaded on each boot, including any filtering which was desired. The logo, date prompt, time prompt, caps lock, cursor character, cursor blink, etc. were also customizable. These were all done by using the SYSTEM command to make your selections and then using the CONFIGR command to write them to disk so that they would automatically load on reboot (if you wished to do so). DOSPLUS 3.5 could support the existence of different CONFIGR files on the same disk and could change between them on the fly.

Job Control Language

Unlike the DO command, DOSPLUS 3.5’s JCL executor was a real language and had to be loaded into high memory (using the SYSTEM command) before it could be operated. Once in memory, batch files could be created with substitutional parameters and conditional execution.

Included Utilities:

Zaps

Forcing VERIFY in DOSPLUS v3.4 – R. Baker

Using AUTO to turn on Verify at every boot-up in DOSPLUS v3.4 not only slows the boot process, it also corrupts memory above 5200H. This gets you if you are trying to reenter the Electric Pencil, for example. Or if you are trying to DUMP code in that area. So to force Verify to be on all the time unless turned off use DISKDUMP to zap SYS0/SYS.H4, File Relative Sector 1, at byte CF from C3 2A 48 to C3 47 48

Zap – Disabling Passwords in DOSPLUS v3.4

Use DISKDUMP to zap SYS2/SYS.H4, File Sector 1, at byte C8 from E1 28 37 to E1 18 37

DOSPLUS 3.5 Conventions

• Capital letters MUST be typed as shown on command lines.
• Information to be entered by the user based upon a list of valid values and parameters for that command are given in lower case.
• Brackets indicate that the information contained within the brackets is optional and may or may not be entered, depending on the situation and the user’s desire for clarity.
• Parentheses indicate the parameter field. This field is composed of those parameters that will modify the action of the command to suit the user’s needs. Parentheses are not a requirement in DOSPLUS; the parameter field is now indicated as much by position as by delimiters.
• Parameters may be abbreviated by using the capital letter(s) of the parameter name. Lowercase letters may or may not be typed, depending on the user’s need for clarity.
• The letter H indicates that the value it follows is a hexadecimal value. It is used for entering data to the system in hexadecimal format.
• The form of each command will be the command itself, followed by the I/O field, followed by the parameters field. The parameter field and certain portions of the I/O field are optional and included at the discretion of the operator.

DOSPLUS 3.5 Library Command Reference

device1/file1 – source device or file

device2/file2 – destination device or file

Strip=sw – backspace destination file 1 byte

devspec ? name of device for which driver is to be installed

filespec – name of driver program

devspec1 – source device

drivespec1 – source drive

devspec2 – destination device

drivespec2 – Destination drive

filespec – file with attributes to be altered

wildmask – file or group of files to be operated on (use ?,*,! to mask characters)

PW=”” – disk master password

Acc=”” – new access password

Upd=”” – new update password

Prot=value – protection

Lrl=sw – new logical record length

Inv=sw – new invisible status

Keep=sw – new non-shrinkable status

Mod=sw – new mod flag status

[drivespec] – optional drive specifier

[doscmd] – any executable DOSPLUS command.

* – disables <ENTER> as break on boot & disables BREAK

! – invisible command

ON – enable BREAK key
OFF – disable BREAK key

devspec – any valid device specification

filespec – any valid file specification
Append=sw – build onto existing file

drivespec – any valid drive number
file – optional output file
device – optional output device

wildmask – file or group of files to be operated on (use ?,*,! to mask characters)
System=sw – display files as standard entries
Invis=sw – display visible and invisible files
Kill=sw – display names of deleted files
Alpha=sw – display names in alphabetical order

filespec – optional file specification
Start=val – starting memory address
End=val – ending memory address
Data=val – optional fill data

ON – turns display on
OFF – turns display off

drivespec – optional drive specification
Wp=sw – sets software write protect
Md=sw – configures for delay on motor on
HL=sw – configures for delay on head load
Step=sw – sets drive step rate
SKip=sw – sets double-step mode
SIZe=sw – indicates disk’s physical size
SIDes=sw – indicates number of read/write surfaces
Pd=sw – indicates physical drive

drivespec – optional drive specification
Wp=sw – sets software write protect
Step=sw – sets drive step rate
SIZe=sw – sets platter size
SIDes=sw – indicates number of read/write surfaces
Pd=sw – indicates physical drive
Ho=val – sets head offset
Co=val – sets cylinder offset
Ts=val – sets number of tracks per sector

device – any valid device

file – any valid file
filespec – any valid file specification
drivespec – any valid file specification
devspec – any valid device specification
wildmask – file or group of files to be operated on (use ?,*,! to mask characters)
Dpw=”” – destination drives master password
Echo=sw – display filenames as copied
Invis=sw – copy invisible files also
Kill=sw – delete source file after copying
Mod=sw – copy based on MOD flag condition
Over=sw – prompt before overwriting
Prompt=sw – prompt for disks (single-drive copy)
Query=sw – prompt before copying
Spw=”” – source disk’s master password
Tiny=sw – copy one sector at a time
New=sw – copy only files not on destination
Old=sw – copy only file on destination

filespec – any valid file specification
Data=val – fill data (one or two bytes)
Grans=val – number of grans
Keep=sw – sets keep flag (non-shrinkable attrib.)
Kilo=val – number of kilobytes
Lrl=val – logical record length
Size=val – number of records
Verify=sw – verify disk space after creation

mm – two-digit month (1-12)
dd – two-digit day (1-31)
yy – two-digit year (0-99)

A – set display to ASCII/Graphics
C – Instruction/Call step
Daaaa – set the display to aaaa
Gaaaa,bbbb,cccc – execute at aaaa with breakpoints set at bbbb and cccc
H – set display to hexadecimal
I – single step next instruction
Maaaa – <SPACE> – modify at aaaa. <ENTER> records change and end; <SPACE> records change and moves to next next address
O – exit to DOSPLUS with DEBUG still engaged
Rpr aaaa – alter register pair pr to aaaa
S – full screen display mode
U – set dynamic display update mode
X – set register examine mode
; – advance display to next memory page
– – decrement display to previous memory page

drivespec – optional drive specification
device/file – optional output device or file

wildmask – optional wildmask (?,*,!) to restrict DIR to certain class or group of files
System=sw – display system files
Invis=sw – display visible and invisible files
Kill=sw – display deleted files
Alpha=sw – display files in alphabetical order

filespec – any valid file specification
Break=sw – BREAK key enable/disable
High=val – set high memory before execution

filespec – any valid file specification
Data=sw – indicates that file is non-program file
Start=val – starting memory address
End=val – ending memory address
Tra=val – transfer address

val – optional error message number

devspec – any valid, active device

filespec – the filter program
YES – engage filter after loading (assumed) or engage previously loaded filters
NO – load but do not engage filter or deactivate a previously loaded filter
MAP – display filter codes

devspec – primary device to be routed

device/file – device or file to which primary device is to be routed

Page=val – number of physical line on page
Lines=val – number of lines per page to be used
Width=val – number of characters per line
Top – immediate top-of-form mode
Code=val – sends 1 or 2 byte value to printer

drivespec – optional drive specification
device – optional output device

file – optional output file

drivespec – any valid drive number
Mount=sw – logs in disk immediately

devicespec – primary device to be linked
device – device with which primary device is to be linked

file – file with which primary device is to be linked

filespec – name of file to be deleted
wildmask – optional group of files to be deleted (use ?,*,! to mask characters)
devspec – name of device to be deactivated

drivespec – name of drive to be removed from system
Inv=sw – include or not invisible files in delete
Echo=sw – display filename as being deleted
Sys=sw – include or not system files in delete
Query=sw – prompt before deleting files
Pw=”” – declares DISK master password to system

device – any valid output device in the system

file – any valid output file

device1 – source device

file1 – source file
device2 – destination device
file2 – destination file
Ctl=sw – determines whether or not control codes (ASCII 00H-1FH) will be output unchanged or displayed as periods

filespec – name of file to be loaded
Prompt=sw – prompt for disk mounts or not
Run=sw – execute file upon load or not
Tra=address – control address to be transferred to if file is to be executed

message – optional message string

drivespec – drive specification
Pw=”” – supplies current disk master password
Mpw=”” – supplies new password to system
Name=”” – specifies new name for diskette
Date=”” – specifies new date for diskette
Lock=sw – whether disk master password is to be assigned to, or removed from, all files in the directory or not
Acc=sw – if LOCK=Y, disk master password is assigned as ACCESS password of all files if LOCK=N, ACCESS passwords are removed
Upd=sw – if LOCK=Y, disk master password is assigned as UPDATE password of all files if LOCK=N, UPDATE passwords are removed
Clean=sw – zero or not unused entries in directory

device1 – device being renamed

file1 – file being renamed
device2 – new name for device
file2 – new name for file

devspec – current logical name of device

drivespec – current logical name of disk drive

Baud=val – sets baud rate

Word=val – sets word length

Stops=val – sets number of stop bits

Parity=sw – engage/disengage parity error checking

Even=sw – configures for even parity

Odd=sw – configures for odd parity

Dtr=sw – sets/resets DTR line

Rts=sw – sets/resets RTS line

BReak=sw – sets RS232 break status

device – optional output device

file – optional output file

filespec – name of configuration file

Time=sw – enable/disable time prompt

Date=sw – enable/disable date prompt

Logo=sw – enable/disable logo

Blink=sw – enable/disable blink cursor

Caps=sw – toggle caps mode (upper/lower case)

CUrsor=val – define cursor character

High=val – set top of memory pointer

Step=val – set system default drive step rate

SAve=sw – effect permanent changes

Port=val – address of port to be output on powerup

Mode=val – one byte value to be output to this port

hh – two-digit hour (00-23)
mm – two-digit minute (00-59)
ss – two-digit second (00-59)

ON – engage verify
OFF – disengage verify

DOSPLUS 3.5 Utility Command Reference

:sd – drive being copied from
:dd – drive being copied to
Date=”” – date or range of dates
Use=”” – overwrite files without being prompted

:sd – source drive
:dd – destination drive
:dr – any valid drive
wildmask – valid DOSPLUS wildcard specification (use ?,*,! to mask characters)
CAT=sw – display directory of TRSDOS 1.3
DIR=sw – same as CAT
Echo=sw – display filenames as files are copied
Invis=sw – operate on invisible and visible files
System=sw – operate on system and non-system files
Over=sw – overwrite or not a file
Query=sw – query or not before copying files
V12 – convert from TRSDOS 1.2 or earlier
V13 – convert from TRSDOS 1.3
Mod1=sw – use double-density diskette (Mod I)

:dr – drive containing directory to be checked
filespec – optional output file
devspec – optional optional device specification

Cyl0 – ignore possible error on Model I double- density diskette boostrap file
Files – repair faulty file directory entries
Gat – repair faulty Granule Allocation Table
Hit – repair faulty Hash Index Table

filespec – name of file to be examined or modified
Commands

; – advance one sector

– – go back one sector

+ – advance to end of file

= – go to beginning of file

F – find hexadecimal value

G – go to specified sector

M – enter modify mode

P – locate address in load module file

@ xx – fill xx bytes with 00 byte, starting at current cursor location

@ xxyy – fill yy bytes with xx byte, starting at current cursor location

Set – alter disk drive parameters
Fill – fill sectors with specified byte
Copy – copy sectors
Print – print hardcopy of selected sectors
Verify – read and check specified sectors
Format – format a selected track or tracks
Display – display or modify diskette sectors Display commands:

; – increment display one sector

+ – increment display one cylinder

– – decrement display one sector

= – decrement display one cylinder

BREAK – return to main menu

M – enter modify mode

Modify commands:

right arrow – increment cursor position 1 byte

down arrow – increment cursor position 1 row

left arrow – decrement cursor position 1 byte

up arrow – decrement cursor position 1 byte

BREAK – abort modify mode without save

ENTER – end modify mode with save

CLEAR – toggle hexadecimal/ASCII display

@ xx – fill current sector with 00 bytes

@ xxyy – fill current sector with yy bytes with xx bytes

:dr – drive containing diskette for formatting
Date=”” – set format date {01/01/80}
Pw=”” – specify disk master password {none}
Name=”” – specify disk name {none}
Cyls=val – specify number of cylinders {40}
Sides=val – specify single/double-headed format {1}
Den=”” – specify single (S) or double (D) density
Use=”” – override (Y) or not (N) prompt for previously formatted diskette {N}

command – valid DOSPLUS command or program
filespec – output file name
@devspec – output device specification

@DO – video display

@KI – keyboard

@PR – printer

@RS – serial port

@U1 – user defined

@U2 – user defined

:dr – disk drive specification
filespec – output file name
@devspec – output device specification

@DO – video display

@KI – keyboard

@PR – printer

@RS – serial port

@U1 – user defined

@U2 – user defined

wildmask – valid DOSPLUS wildcard specification (use ?,*,! to mask characters)
System – include system files
Invis – include invisible files
Hex – provide cylinder and sector numbers in hex

filespec1 – any valid filespec
filespec2 – any patch format file
patname – name of patch to be removed
Kill=sw – remove patch from file

filespec – name of KILLed file

:dr – drivespec for media
filespec – optional bootstrap program
Xder=val – specify control address on system reset

B – adjust baud rate (Model III)

H – print help list

I – re-initialize program

L – load a disk file

M – map out program area

O – offset program

Q – exit to DOSPLUS

R – read a system tape

S – save a disk file

W – write a system tape

DOSPLUS 3.5 Drivers and Filters Reference

filespec – optional MACROKEY definition file
Db=val – debounce delay
RD=val – delay before key repeat begins
RR=val – key repeat rate

Ucase=sw – enable/disable lower case (Model I)
Blink=val – set cursor blin rate (Model I)

Lf=sw – linefeeds are sent to printer after CR
Null=sw – printer advance a line when null is printed
SPool=val- optional spool buffer size
Max=val – optional number of attempts to output character to printer in spooler interrupt
Indent=val – number of spaces to indent text
Xlate=sw – whether to translate formfeed characters
Serial=sw – whether parallel or serial driver is used
Delay=sw – optional number of char. after LF or CR
Cts=sw – optional handshaking parameter
DSr=sw – optional handshaking parameter
Cd=sw – optional handshaking parameter
Ri=sw – optional handshaking parameter
INVert=sw – whether handshaking is normal or inverted

There are no parameters for this driver

:dr – disk drive specification
filespec – file containing disk file
Size=val – initialize library of specified size
Inst=sw – install itself into operating system

DOSPLUS 3.5 Job Control Language Reference

PROC – procedure buffer size (768 to 4096 bytes) {768}
QUEUE – keyboard queue (256 to 4096 bytes) {256}

jclprog – JCL program file
<exp> – parameters

/DOS <exp> – pass DOSPLUS command line to command interpreter
/EXIT – terminate JCL execution
/READ $var1 $var2 – accept input from keyboard or queue
/TYPE <exp> – display messages on video
/PRINT <exp>- display messages to lineprinter
/IF <exp1> <relation> <exp2>/JCL command – make logical comparisons of JCL variables and decisions based on those comparisons
/GOTO -label – alter normal program flow
/QUEUE <exp> – place data in keyboard queue
/QLOAD filespec – load keyboard queue with data stored in disk file
/PURGE – purge keyboard queue
/QUEUE /Jump -label – place special characters in queue
/RESUME – return to program interrupted by /JUMP
/CANCEL – allow JCL procedure entered through /JUMP to avoid returning to intercepted program
/RUN filespec <exp1> <exp2> <exp3> – execute another JCL program
/DEBUG – invoke DOSPLUS 3.5’s DEBUG monitor
/VOFF – suppress display of data read from queue
/OPTION <parm>/switch <parm>/switch <parm>/switch

DSP – whether data is displayed on video
JCL – print trace of JCL activities during execution
QUEUE – turn keyboard queue on/off
QBYTE – enable/disable queue from responding to single-character input
DQ – copy all data output to video display into queue
CHR – determines how special characters read from queue are handled

DOSPLUS 3.5 Disk BASIC Extensions

filespec – optional file specification
-F:nn – number of files (0-15) to be open at one time
-M:nnnn – highest memory address BASIC will use

filnum – optional file number (1-15) to be closed; if omitted; all files are closed

CMD”O”,exp,+ or -,AN(se),KA-KA,TA,TA

sort arrays

exp – expression to indicate number of elements
+ or – – primary key in ascending or descending order
AN(se) – primary key array with starting element no.
+KA – next key array (ascending order)
-KA – next key array (descending order)
TA – first tag array
TA – next tag array

CMD”REF”, option ,option,…

S= – single variable,line, or keyword
V – all variables
L – all line numbers
K – all keywords
P – printer

CMD”RENUM”, nln, inc, sln, eln

renumber BASIC text

nln – new line number {10}
inc – increment {10}
sln – starting line number {top of text}
eln – ending line number {end of text}

nln – new line number {10}
inc – increment {10}
sln – starting line number {top of text}
eln – ending line number {end of text}

CMD”SR”, sexp, rexp, sln-eln

global editing of BASIC text

sexp – search expression
rexp – replacement expression
sln-eln – optional starting and ending lines

CMD”X devspec/filespec -V/-L,<title>”

cross reference

devspec/filespec – data destination (*do)
-V – crossref all variables
=var – crossref only specified variable
-L – cross ref all lines
=line – crossref only specified line
<title> – title for current crossref list

dddd – one to four digit hexadecimal value

var$ – inverses MKD$ with 8 byte string

var$ – inverses MKI$ with 2 byte string

var$ – inverses MKD$ with 4 byte string

DEF FN name(var)=exp

define function
name – variable used to name function
var – variable(s) to be passed to function
exp – function desired

DEFUSRn = address

Define entry address for machine-language subroutine
n – USR routine number (0-9)
address – machine language entry point

pln – present line number
nln – new line number

pln – present line number
nln – new line number

filnum – file buffer being interrogated

FIELD filnum,num AS var$,num AS var…

Partition the buffer used with a random file

filnum – file buffer number specified in OPEN
num – length of that field
var$ – variable name for the field

GET filnum, recnum

read record from random file

filnum – file buffer number
recnum – logical record number

INPUT@ <pos>,”prompt”,fl,it;var$

controlled input
<pos> – screen position
“prompt” – prompt message to be displayed
fl – integer expression of field length
it – item type flag ($ = alphanumeric, # = numeric, * = return on field full)
var$ – string variable for input field

INPUT# filnum,var,var,var…

sequential file input
filnum – file buffer number of file
var – variable containing information read in

INSTR (pos,targ$,sub$)

string search function

pos – optional position; 1 is assumed
targ$ – name of string to be searched
sub$ – sub-string to be searched for

filespec – standard DOSPLUS file specification

LINE INPUT”prompt”;var$

keyboard line input

prompt – optional prompt to be displayed
var$ – name of string to return information

LINE INPUT# filnum,var$

input line from disk file

filnum – file buffer number of sequential file
var – variable name to store the string

LOAD “filespec”,option

load program from disk

filespec – standard DOSPLUS file specification
option – one or more special options to engage

R – runs program after loading; open file will not be closed
V – preserves current set variables and FIELD
line number – begins execution at line number specified when R option is used

filnum – file buffer number being interrogated

filnum – file buffer number being interrogated

LSET (or RSET) var$=exp$

Fill output buffer

var$ – variable defined via FIELD statement
exp$ – string expression to be placed in buffer

MERGE “filespec”

Merge ASCII file with resident program

filespec – standard DOSPLUS file in ASCII format
option – optional switch R to not interrupt program execution after new file is loaded

MID$ (var$,pos,len=rep$)

Replace portion of a string

var$ – name of string to be edited
pos – starting position of replacement
len – specifies number of character to be replaced
rep$ – string to be replaced with var$

new$=MID$(old$,pos,len)

duplicate portion of string

new$ – string created in this operation
old$ – original string information to duplicate
pos – point of old$ to start duplicating from
len – number of characters to duplicate

exp – returns 8 byte string; double pre

exp – returns 2 byte string; integer precision

exp – returns 4 byte string; single precision

OPEN “mode”,filenum,”filespec”,lrl

Open disk file

mode – I/O mode intended for file
R – random access mode
D – direct access; same as R
I – sequential input mode
E – sequential output extension mode
O – sequential output mode

PRINT# filnum,USING format$,var,del,var…

Output data to a sequential file

filnum – file buffer number of sequential file
USING format$ – optional format string to define data format for the print
var – variable containing data to be written
del – delimiter that must be placed between each variable to be written; may be semi-colon

filnum – file buffer number
recnum – logical record number to be written

RUN “filespec”,option

Load and run a program

filespec – standard DOSPLUS file specification
option – one of three special options

R – any open files will not be closed
V – preserves currently set variables and FIELD
line number – runs program beginning at line no.

SAVE “filespec”,A

Save program

filespec – standard DOSPLUS file specification
A – optional switch to save file in ASCII format

SET EOFn

Set EOF to last record accessed + 1

USRn (var) – call user external subroutine

n – USR routine number
var – variable to be passed to USR

DOSPLUS 3.5 Disk BASIC Shorthand

DOSPLUS 3.5 Disk BASIC Error Messages

DOSPLUS 3.5 Disk BASIC Error Codes