asm context issue?

[britlion]

Code:

asm
sub a,3
end asm

I think this is expecting sub to be the basic context subroutine, not the asm subtract command, so fails to compile?

zxb 1.2.8-s758

[boriel]

According to the ZX Spectrum manual, the Z80 syntax instruction is sub N not sub a, N for 8 bits.
So:

Code:

asm
sub 3
end asm

should work ok.
Try this and tell me :?:

[britlion]

Ugh.

Looks like my reference may be incorrect:

Code:

SUB A,imm8
Operation Subtracts the immediate value from A.
Op Code 11010110 : [imm8]
Flags S Z H C are affected as defined
P/V detects overflow
N is set
T States 7

You're right. It looks like Zilog officially use SUB N - which is inconsistent with all their other instructions! How bizarre!

[boriel]

I used the speccy user manual to get the asm mnemonics! :mrgreen:
Anyway, I will try to make de ASM to allow SUB A, N also. :roll: