Ira Goldklang's TRS-80 Revived Site

TRS-80 Zaps/Patches/Pokes/Tips – NEWDOS/80 v2.0 Unofficial Zaps

by Ira @ 5:47 pm on May 11, 2009.
[Model I]      [Model III]
TRS-80 Model I NEWDOS/80 Version 2 *Unofficial* ZAPS
     		[Model IV]      [Model 100]



Add “,B” parameter to PDRIVE to Change in Resident RAM Only – Model I
This zap allows temporary ‘in memory’ change of the PDRIVE table thereby not altering the disc record.

Use PDRIVE as normal except ,B is substituted instead of the regular ,A in the PDRIVE command viz: PDRIVE,0,1=7,B.

This will alter the PDRIVE configuration in memory (you can leave the write-protect tab on) and you can do this as many times as required for the next time you RESET your PDRIVE table will not have been affected.

You could then copy SYS16/SYS onto other work discs in use. 

SYS16/SYS,02,FB     change  FE 41 21 20 06
                        to  C3 C0 51 00 00

SYS16/SYS,04,D4     change 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                           00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                        to FE 41 12 20 03 C3 F1 4F FE 42 C2 F7 4F 3E 41 12 77
                           C5 E5 01 00 07 21 E2 4D 71 23 10 FC E1 C1 C3 F1 4F



Add “,B” parameter to PDRIVE to Change in Resident RAM Only – Model III
This zap allows temporary ‘in memory’ change of the PDRIVE table thereby not altering the disc record.

Use PDRIVE as normal except ,B is substituted instead of the regular ,A in the PDRIVE command viz: PDRIVE,0,1=7,B.

This will alter the PDRIVE configuration in memory (you can leave the write-protect tab on) and you can do this as many times as required for the next time you RESET your PDRIVE table will not have been affected.

You could then copy SYS16/SYS onto other work discs in use. 

SYS16/SYS,02,E8     change  7E FE 41 12 20
                        to  7E C3 CB 51 20

SYS16/SYS,04,DF     change 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                           00 00 00 00 00 00 00 00 00 00 00 00 00
                        to FE 41 12 20 03 C3 E0 4F 3D FE 41 20 F8 C5 E5 01 00
                           07 21 D3 4D 71 23 10 FC E1 C1 18 E3 02



Boot In Lower Case – Model III
 
SYS0/SYS,11,2F      change  28 05
                        to  00 00



Boot in 4MHz on the Model 4 – Model 4
 
SYS0/SYS,13,B4 change  00 00 00 00 00 00 00 00 00 00 00 00
                   to  3A 10 42 F6 40 32 10 42 C3 B6 48 00

SYS0/SYS,11,DF change  C3 B6 48
                   to  C3 A8 50

Also execute the command SYSTEM,0,BJ=2



Correct date & time updating on warm boot – Model 4
 
SYS0/SYS,02,20 change  1E 20 0D 36 1E 21
                   to  19 20 0D 36 19 21



Allow the date in DD/MM/YY format – Model Unknown
 
SYS0/SYS,12,2B change  20 ED
                   to  00 00

SYS0/SYS,12,3E change  20 ED
                   to  00 00

SYS0/SYS,13,4E change  4D 4D 2F 44 44 2F
                   to  44 44 2F 4D 4D 2F



Allow the date in DD/MM/YY in the FORMAT commands – Model Unknown
 
SYS6/SYS,12,45 change  32
                   to  34



Display DIRectories without Clearing the Screen – Model Unknown
 
SYS8/SYS,00,DE change  CC 8F
                   to  21 8F

Comments are closed.

[Ira Goldklang’s TRS-80 Revived Site is proudly powered by WordPress.]