Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
3
CP/M-86 V1.1
Patch 02, LDCOPY, 3/08/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
Program: LDCOPY.A86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-00900
Error Description:
LDCOPY does not write the loader to the destination disk with a
track buffered BIOS.
Patch Procedure:
Change the distributed assembly file of the load copy program
according to the following procedure. Instructions are modified in
the Write routine.
1) Locate the label trysec:.
2) Locate the instruction just after the label jz tryread.
3) Add the following code:
mov cl, 00
mov ax, track
inc ax
cmp ax, nlt
jne normal_write
mov ax, sector
inc ax
cmp ax, spt
jne normal_write
mov cl, 01
Normal_Write:
.
.
.
4) Locate the beginning of the code segment, for example, Cseg.
5) Locate the copyright notice: (copyright (c) 1981, Digital
Research).
6) Just after the copyright, add:
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1 Patch 02
rs 100H ;emergency patch area
.
.
.
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
2
CP/M-86 V1.1
Patch 03, GENDEF, 4/8/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
DDT-86 is a trademark of Digital Research.
Program: GENDEF.CMD
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Error Description:
This patch corrects the GENDEF.CMD program to parse the
parameters in the command tail.
Patch Procedure:
Make a back-up copy of GENDEF.CMD before using DDT-86 to make
the following changes:
A>ddt86
DDT86 1.1
-rgendef.cmd
START END
NNNN:0000 NNNN:25FF
-xcs
CS 0000 nnnn+8 ; The effect of the register
DS 0000 nnnn+8 ; change is to set all segment
SS 0040 nnnn+8 ; registers to the beginning of
ES 0000 nnnn+8 ; the program. ( above the base page)
IP 0000 .
-aede
NNNN+8:0EDE mov bx, 06d
NNNN+8:0EE1 cmp byte [bx], 24
NNNN+8:0EE4 nop
NNNN+8:0EE5 nop
NNNN+8:0EE6 .
-aefb
NNNN+8:0EFB mov bx, 06d
NNNN+8:0EFE mov al, [bx+si]
NNNN+8:0F00 nop
NNNN+8:0F01 nop
NNNN+8:0F02 .
-wgendef.cmd
-^c
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1
Patch 04, ED, 04/08/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
DDT-86 is a trademark of Digital Research.
Program: ED.CMD
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Change Description:
Usually, you press CTRL-C to interrupt ED commands. If ED
g the command before the CTRL-C is pressed, ED
aborts causing termination of the edit session. The following patch
procedure modifies ED to allow interruption of commands using CTRL-Y
instead of CTRL-C.
Patch Procedure:
Make a back-up copy of ED.CMD before using DDT-86 to make the
following changes:
A>ddt86
-red.cmd
START END
nnnn:0000 nnnn:23ff
-xcs
CS 0000 nnnn+8
DS 0000 nnnn+8
SS 0000 nnnn+8
ES 0000 nnnn+8
-lbd1,bd3
yyyy:0BD1 CMP AL,03
yyyy:0BD3 JNZ 0BD9
-sbd2
yyyy:0BD2 03 19
yyyy:0BD3 75 .
-s79
yyyy:0079 30 31
yyyy:007A 36 .
-wed.cmd
-^c
A>
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1
Patch 05, ED, 04/08/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
DDT-86 is a trademark of Digital Research.
Program: ED.CMD
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Change Description:
Use the ED command, 0X<filename>, to delete files. If the
command is used with a filename that does not exist, however, ED
prints the message, BREAK "O" AT ^Z, and interrupts any macro command
being processed. The following patch procedure modifies ED to omit
the interruption of macro commands and the error message display.
Patch Procedure:
Make a back-up copy of ED.CMD before using DDT-86 to make the
following changes:
A>ddt86
-red.cmd
START END
nnnn:0000 nnnn:23ff
-xcs
CS 0000 nnnn+8
DS 0000 nnnn+8
SS 0000 nnnn+8
ES 0000 nnnn+8
-l8e9,8f7
yyyy:08E9 CMP BYTE [0259],FF
yyyy:08EE JNZ 08BA
yyyy:08F0 MOV BYTE [03C6],4F
yyyy:08F5 JMP 01F7
-a8e9
yyyy:08E9 jmp 8ba
yyyy:08EC .
-f8ec,8f7,90
-s79
yyyy:0079 30 32
yyyy:007A 36 .
-wed.cmd
-^c
A>
Licensed users are granted the right to include these changes in
CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1
Patch 06, BDOS, 4/23/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
ASM-86 and DDT-86 are trademarks of Digital Research.
Program: CPM.SYS and CPM.H86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Error Description:
This patch modifies Functions 17 and 18 (Search First and
Search Next) to return the directory record in the DMA address.
Usually, the data segment contains the address segment attribute.
However, in the following patch procedure, it is assumed that the
DMA buffer segment set by Function 51 (Set DMA Base) contains the
address segment attribute.
Patch Procedure:
Make a back-up copy of CPM.H86 and CPM.SYS before making the
following changes. Assemble the following program using ASM-86
. Concatenate the program to the end of CPM.H86 and the TBIOS.
Refer to the CP/M-86 Microcomputer Control Program System Guide for
concatenation instructions. Include all previous patches in this
concatenation.
Title 'Dmapatch 4/23/82'
Dmabase Equ Word ptr 24A2H
Patch_Area Equ 1896H
Cseg
Org Patch_Area
Mov Es, .Dmabase
End
Or, you can use DDT-86 to patch the CPM.SYS file directly
with the following commands:
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1 Patch 06
A>ddt86
DDT86
-rcpm.sys
START END
NNNN:0000 NNNN:397F
-s1918
NNNN:1918 9D a2
NNNN:1919 24 .
-wcpm.sys
-^c
A>
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
2
CP/M-86 V1.1
Patch 07, BDOS, 4/21/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
ASM-86 and DDT-86 are trademarks of Digital Research.
Program: CPM.SYS / CPM.H86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Error Description:
Register BH contains random data upon return from Function 12.
This patch forces the BDOS to return 0.
Patch Procedure:
Make a back-up copy of CPM.SYS and CPM.H86 before making the
following changes. Assemble the following program using ASM-86 .
Concatenate the program to the end of CPM.H86 and the TBIOS. Refer
to the CP/M-86 Microcomputer Control Program System Guide for
concatenation instructions. Include all previous patches in this
concatenation.
Title 'Func12 4/21/82'
;This patch sets BH to 0 when bdos returns from function 12
Cseg
Patch_Area Equ 0B77H
Org Patch_Area
Xor Ax, Ax
End
Or, you can use DDT-86 to patch the CPM.SYS file directly
using the following commands:
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1 Patch 07
A>ddt86
DDT86
-rcpm.sys
START END
NNNN:0000 NNNN:397F
-sbf7
NNNN:0BF7 32 33
NNNN:0BF8 C0 .
-wcpm.sys
-^c
A>
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
2
CP/M-86 V1.1
Patch 08, BDOS, 5/12/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
DDT-86 and SID-86 are trademarks of Digital Research.
Program: CPM.SYS and CPM.H86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Error Description:
The E command (Program Load) in DDT-86 or SID-86 might
overwrite part of DDT-86, SID-86 or other memory locations if a
drive specification is part of the filespec used in the E command.
This error might also occur if you use Function 59 with a drive
specification in the FCB.
Patch Procedure:
There are two ways to patch the system. The first requires
assembly of the program stub titled FUNC59P, which appears below.
Concatenate the assembled FUNC59P to the CPMX.H86 file, CPMX.H86 =
CPM.H86 + CBIOS.H86. The command to concatenate is PIP
CPM.H86=CPMX.H86,FUNC59P.H86. Then, use GENCMD with the command
GENCMD CPMX 8080 code[a40] and rename the CPMX.CMD to CPM.SYS.
Title 'FUNC59P'
;
; This program restores the ES reg after a call to Function 59
Cseg
Org 0E23H
Push Es
Nop
Mov .22DCH, Dx
Org 0F1AH
Jmp Patch_area
Nop
Org 0A20H
Patch_area:
Mov .2496H, Ax
Pop Es
Ret
End
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1 Patch 08
Or, you can apply the following patch using DDT-86. The patch
is applied below the FUNC59P program stub. Make a back-up copy of
CPM.SYS before using DDT-86 to make the following changes:
A>ddt86
rcpm.sys
START END
NNNN:0000 NNNN:397F
-saa0
NNNN:0AA0 00 a3
NNNN:0AA1 00 96
NNNN:0AA2 00 24
NNNN:0AA3 00 07
NNNN:0AA4 00 c3
NNNN:0AA4 00 .
-sea3
NNNN:0EA3 A1 06
NNNN:03A4 99 90
NNNN:0EA5 24 89
NNNN:0EA6 A3 16
NNNN:0EA7 DC .
-sf9a
NNNN:0F9A A3 e9
NNNN:0F9B 96 03
NNNN:0F9C 24 fb
NNNN:0F9D C3 90
NNNN:0F9E E9 .
-wcpm.sys
-^c
A>
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
2
CP/M-86 V1.1
Patch 09, PIP, 05/14/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
DDT-86 is a trademark of Digital Research.
Program: PIP.CMD
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Error Description:
A problem occurs using PIP to ambiguously copy archived,
multiextent files. PIP copies only the last extent.
Patch Procedure:
Make a back-up copy of PIP.CMD before using DDT-86 to make
the following changes:
A>ddt86
DDT86 1.1
-rpip.cmd
START END
nnnn:0000 nnnn:1D7F
-xcs
CS 0000 nnnn+8
DS 0000 nnnn+8
SS 0040 nnnn+8
ES 0000 nnnn+8 ; YYYY = nnnn+8
-l132A
YYYY:132A MOV CL,[02B9]
YYYY:132E NOT CL
YYYY:1330 PUSH CX
YYYY:1331 CALL 13B6
YYYY:1334 POP CX
YYYY:1335 OR AL,CL
YYYY:1337 RCR AL,1
YYYY:1339 JNB 1375
YYYY:133B MOV BYTE [01E4],00
-a132a
YYYY:132a test byte [02b9],01
YYYY:132f jz 1338
YYYY:1331 call 13b6
YYYY:1334 rcr al,1
YYYY:1336 jnb 1375
YYYY:1338 xor al,al
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1 Patch 09
YYYY:133a mov [0198],al
YYYY:133d mov [01e4],al
YYYY:1340 .
-wpip.cmd
-^c
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
2
CP/M 86 V1.1
Patch 10, BDOS, 5/20/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
ASM-86 and DDT-86 are trademarks of Digital Research.
Program: CPM.SYS and CPM.H86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Error Description:
CP/M-86 does not return an error indication code for an invalid
function code. This patch forces the BDOS to return 0FFFFH in AX
and BX if a function code is out of range.
Patch Procedure:
To patch the CPM.H86 file, assemble the following program stub
with ASM-86 and name it BADFUNC.H86. Concatenate BADFUNC.H86 to
the end of the CPM.H86 file using the PIP command:
A>PIP CPM.H86=CPM.H86,BADFUNC.H86
The modified CPM.H86 file replaces the original. You can use the
modified CPM.H86 file with your CBIOS to build a system. Refer to
the CP/M-86 Microcomputer Control Program System Guide for
information on the organization of CPM.SYS. Make a back-up copy of
CPM.SYS and CPM.H86 before making the following changes:
Title 'BAD FUNC NUMB 5/20/82'
;
; This program patches CPM86 V1.1 so it returns an 0FFFFH
; in BX and AX.
;
CSeg
Org 0A50H
Label_0:
Jb OK
Mov Word ptr .249bH, 0FFFFH
Ret
Ok:
Jmp Label_1
Org 0B94H
Jmp Label_0
Org 0B97H
Label_1:
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1 Patch 10
End
Or, you can patch the CPM.SYS file directly using DDT-86 .
Make a back-up copy of CPM.SYS before making the following changes:
A>ddt86
DDT86 1.1
-rcpm.sys
START END
NNNN:0000 NNNN:397f
-s0ad0
NNNN:0AD0 44 72
NNNN:0AD1 65 07
NNNN:0AD2 63 c7
NNNN:0AD3 65 06
NNNN:0AD4 6D 9b
NNNN:0AD5 62 24
NNNN:0AD6 65 ff
NNNN:0AD7 72 ff
NNNN:0AD8 20 c3
NNNN:0AD9 32 e9
NNNN:0ADA 38 3b
NNNN:0ADB 20 01
NNNN:0ADC 38 .
-s0c14
NNNN:0C14 72 e9
NNNN:0C15 01 b9
NNNN:0C16 C3 fe
NNNN:0C17 8A .
-wcpm.sys
-^c
Licensed users are granted the right to include these changes
in CP/M-86 V1.1 software.
All Information Presented Here is Proprietary to Digital Research
2
CP/M-86 V1.1
Patch 11, BDOS, 5/20/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
ASM-86 and DDT-86 are trademarks of Digital Research.
Program: CPM.SYS and CPM.H86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746
through C86-000-01001
Error Description:
If the system denies an absolute memory request, the system
does not return an error-indication code. This patch returns 0FFFFH
in AX if the system denies a memory request.
Patch Procedure:
To patch the CPM.H86 file, assemble the following program stub
using ASM-86 and name the file PATCH11.A86. Concatenate
PATCH11.A86 to the end of the CPM.H86 file using the following PIP
command:
A>PIP CPM.H86=CPM.H86,PATCH11.H86
The modified CPM.H86 file replaces the original. Use CPM.H86 with
your CBIOS to build a system. Refer to the CP/M-86 Microcomputer
Control Program System Guide for information on the organization of W
the CPM.SYS file.
Title 'Patch11 5/20/82'
Loaderr_loc Equ 0F1EH ;Addr of load error routine
Load59_Ret Equ 0F06H ;Exit from load error routine
Pat_offset Equ 0A30H ;Patch area
User_Parm_Seg Equ 02323H ;User's data segment
Aret Equ 0249BH ;Return value
Param_Seg Equ 0249DH ;User's data segment at entry
Cseg
Org Pat_Offset
Patch:
Mov Ax, .User_Parm_Seg
Mov .Param_seg, Ax
Mov Word ptr .Aret, 0FFFFH
Jmp loadret
All Information Presented Here is Proprietary to Digital Research
1
CP/M-86 V1.1 Patch 11
Org Load59_ret
loadret:
Org Loaderr_loc
Jmp Patch
End
Or, you can patch your CPM.SYS file directly using the
following DDT-86 commands. Make a back-up copy of CPM.SYS before
making the following changes:
A>ddt86
DDT86 1.1
-rcpm.sys
START END
NNNN:0000 NNNN:397F
-sab0
NNNN:0AB0 00 a1
NNNN:0AB1 00 23
NNNN:0AB2 00 23
NNNN:0AB3 00 a3
NNNN:0AB4 00 9d
CP/M-86 V1.1
Patch 12, SUBMIT, 5/24/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
DDT-86 is a trademark of Digital Research.
Program: SUBMIT.COM
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746 This patch modifies the SUBMIT utility to enable execution fromtch Procedure:
Make a back-up copy of SUBMIT.COM before using DDT-86 to makees:
A>ddt86
DDT86 1.1
-rsubmit.cmd
START END
nnnn:0000 nnnn:0F7F
-aa2
nnnn:00A2 mov dl,ff ;instruction was mov dx,00h
nnnn:00A4 nop
nnnn:00A5 .
-wsubmit.cmd
CP/M-86 V1.1
Patch 13, BDOS, 06/08/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
ASM-86 and DDT-86 are trademarks of Digital Research.
Program: CPM.H86 and CPM.SYS
Products and Serial Numbers Affected: CP/M-86 V1.1 0-000-00000
An area of memory can be overwritten when a user programram Load).
Patch Procedure:
To patch the CPM.H86 file, type the program stub on the following page into a file named PATCH13.A86. Assemble PATCH13.A86 Concatenate PATCH13.H86 toIP CPM.H86=CPM.H86,PATCH13.H86
The newly modified CPM.H86 file replaces the original and can used with your CBIOS to build a system. Refer to the CP/M-86formation on they modifications.
Title 'PATCH13 6/8/82'
;
; An area of memory may be overwritten when a
; user program executes a Function 59 (program load).
Patch_Area Equ 0A00H
Bdos Equ 00E0H
Cseg
Org Patch_Area
Start_Patch:
Mov Cs:byte ptr .2498H, 01
Push Ax
Mov Ah, Cs:.2327H
Mov Al, Cs:.2313H
Push Ax
Int Bdos
Pop Ax
Mov Cs:.2313H, Al
Mov Cs:.2327H, Ah
Pop Ax
Ret
Nop
Org 0C42H
Jmp Start_Patch
Nop
Nop
Nop
Nop
Nop
Nop
End
Or, you can patch your CPM.SYS file directly using DDT-86 . ng the following changes:
A>ddt86
DDT86 1.1
-rcpm.sys
START END
NNNN:0000 NNNN:397F
-aa80
NNNN:0A80 cs: mov byte [2498], 01
NNNN:0A86 push ax
NNNN:0A87 cs: mov ah, [2327]
NNNN:0A8C cs: mov al, [2313]
NNNN:0A90 push ax
NNNN:0A91 int 0e0
NNNN:0A93 pop ax
NNNN:0A94 cs: mov [2313], al
NNNN:0A98 cs: mov [2327], ah
NNNN:0A9D pop ax
NNNN:0A9E ret
NNNN:0A9F nop
NNNN:0AA0 .
-acc2
NNNN:0CC2 jmp 0A80
NNNN:0CC5 nop
NNNN:0CC6 nop
NNNN:0CC7 nop
NNNN:0CC8 nop
NNNN:0CC9 nop
NNNN:0CCA nop
NNNN:0CCB .
-wcpm.sys
-^c
CP/M-86 V1.1
Patch 14, TRACK.A86, 8/1/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
ASM-86 is a trademark of Digital Research.
Compiled October 1982
Program: TRACK.A86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-007460
Error Description:
Assembling TRACK.A86 produces a syntax error because of an improper ASM-86 directive.
Patch Procedure:
Make a back-up copy of TRACK.A86. Install this patch with : *#a <cr>
1: *214:15t <cr>
214: dseg
215:
216: cpm_disk rb 1
217: cpm_track rw 1
218: cpm_sec rw 1
219:
220: dma_longword rd 1
221: org dma_longword
222: dma_offset rw 1
223: dma_segment rw 1
224:
225: cur_disk rb 1
226: cur_sec rw 1
227: cur_track rw 1
228: cur_dma rw 1
214: *220:2k <cr>
220: *222:i <cr>
222: dma_longword equ dword ptr dma_offset
223: ^z <cr>
224: *214:15t <cr>
214: dseg
215:
216: cpm_disk rb 1
217: cpm_track rw 1
218: cpm_sec rw 1
219:
220: dma_offset rw 1
221: dma_segment rw 1
222: dma_longword equ dword ptr dma_offset
223:
224: cur_disk rb 1
225: cur_sec rw 1
226: cur_track rw 1
227: cur_dma rw 1
228:
214: *e <cr>
A>
CP/M-86 V1.1
Patch 15, BDOS, 11/19/82
Copyright 1982 by Digital Research
CP/M-86 is a registered trademark of Digital Research.
DDT-86 is a trademark of Digital Research.
Compiled December 1982
Program: CPM.SYS, CPM.H86
Products and Serial Numbers Affected: CP/M-86 V1.1 C86-000-00746scription:
The BDOS does not load a file with absolute requirements forRA or STACK segments.
Patch Procedure:
Make a back-up copy of CPM.SYS before you use DDT-86 to makeWm.sys
START END
nnnn:0000 nnnn:xxxx (note the value of nnnn)
-hnnnn,8
nnnn+8 nnnn-8 (note the value of nnnn+8)
-xcs
CS 0000 nnnn+8
DS 0000 nnnn+8
SS 0040 nnnn+8
ES 0000 nnnn+8
IP 0000 .
-add4
nnnn+8:0DD4 jmp 24e2
nnnn+8:0DD7 .
-a24e2
nnnn+8:24E2 cmp word 03[si],0000
nnnn+8:24E6 jz 24f2
nnnn+8:24E8 push ax
nnnn+8:24E9 mov ax,03[si]
nnnn+8:24EC mov [22d4],ax
nnnn+8:24EF pop ax
nnnn+8:24FO jmps 24f5
nnnn+8:24F2 mov [22d4],ax
nnnn+8:24F5 jmp 0dd7
nnnn+8:24F8 .
-wcpm.sys
-^C
A>
Or, you can assemble the following code file (PATCH15.A86) tooncatenate PATCH15.H86 to the end of theM.H86=CPM.H86,PATCH15.H86
The newly modified CPM.H86 file replaces the original and can with your CBIOS to build a system. Refer to Section 7.2 into study theodifications.
;
; The BDOS does not properly load a CMD file with absolute
; load addresses specified in the header record for EXTRA
; and/or STACK segments.
Patch_area equ 24E2h
Jmp_point equ 0DD4h
Patch_return equ 0DD7h
Pag0 equ word ptr .22D4h
Abs equ word ptr 3
CSEG
org jmp_point
jmp patch
CSEG
org patch_return
Patch_ret:
CSEG
org patch_area
Patch:
cmp abs[si],0 ! jz from_ax
push ax
mov ax,abs[si]
mov pag0,ax
pop ax
jmps end_patch
From_ax:
mov pag0,ax
End_patch:
jmp patch_ret
end
Licensed users are granted the right to include these changesed Here is Proprietary to Digital Research
