Jump command

[cym13]

I am dealing with the code:

@10
D=A
@20
A=D+A;JMP

What should be the value of PC after the last command? 20 (the old value of A) or 30 (the new value)?

[cadet1620]

cym13 wrote

I am dealing with the code:

@10
D=A
@20
A=D+A;JMP

What should be the value of PC after the last command? 20 (the old value of A) or 30 (the new value)?

This is undefined behavior. A C-instruction that changes A must not include a jump.

See this thread.

--Mark

[cym13]

Thank you very much!