I don't have experience of 8051 but looking at your code, something like,
Code:
START ORG $1000
MOVE.B #$1,D3 ;preload with 1
MOVE.B D6,D1
CMP.B #"i",D1 ;compare to i
BEQ Done ;if same then we're done
MOVE.B #$5,D3 ;preload with 5
CMP.B #"v",D1 ;compare with V
BEQ Done
MOVE.B #$10,D3 ;preload with 10
CMP.B #"x",D1 ;compare with x
BNE Error
Done
;got value
Error
;something wrong
END START
Should work.
You should also consider setting bit 5 of D3 so it is not case sensitive.
If it's 68k then it should have worked unless the compiler doesn't accept "A" instead of 0x41. You did put some code where the two comments were didn't you?
i didnt understand about your command.
for the code that i ve write above,
it should be like this..
when i enter 49 in the D6,
it should copy 49 in D1 and show the answer 1 in D3