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JNZTEST.ASM
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Assembly Source File
|
2000-06-30
|
2KB
|
64 lines
;
; Test of alleged bug in DCON and DDT
; where JZ and JNZ supposedly trace
; incorrectly. Result: no bug found.
; 05/28/82 and 05/29/82 (Ron Fowler)
; | |
; | |
; | ---> lowercase
; --------------> uppercase
;
ORG 100H
;
;
; TEST | RESULT
; ---- | ------
; |
LOOP: ORI 1 ;RESET Z |
JNZ NOZ1 ;TEST JNZ--------->| went to noz1, as expected
JZ YESZ1 ;TEST JZ---------->| never got here
; |
; CAN'T GET HERE FROM UP THERE |
; (from noz1 or yesz1 only) |
; |
STEP2: XRA A ;SET Z |
JNZ NOZ2 ;TEST JNZ--------->| didn't jump, as expected
JZ YESZ2 ;----------------->| went to yesz2, expected
; |
; CAN'T GET HERE FROM UP THERE |
; |
step3: mvi b,8 ;do a subtraction |
mvi a,8 ;that =0 |
sub b ; |
jnz noz3 ;----------------->| didn't jump here, expected
jz yesz3 ;----------------->| jumped here as expected
; |
; ditto here from there |
; |
step4: mvi b,8 ;do subtraction |
mvi a,9 ; that's nz |
sub b ; |
jnz noz4 ;----------------->| jumped here, as expected
jz yesz4 ;----------------->| never got here, expected
;
; can't be here
;
jmp loop ;but do something anyway
;
; Turnaround here, and proceed to next step
;
NOZ1: JMP STEP2
YESZ1: JMP STEP2
;
NOZ2: JMP step3 ;new further testing
YESZ2: JMP step3
;
noz3: jmp step4 ;one more test
yesz3: jmp step4
;
noz4: jmp loop ;repeat entire test
yesz4: jmp loop
;
end