20 Apr
2006
20 Apr
'06
7:33 a.m.
Although I was well aware of the octal grouping of fields in the 8080, I
adopted hex right off from the start, as I did when coding for the 8008.
The problems dealing with "split" 16-bit quantites was too much of a hurdle
to warrant octal.
As far as memorizing opcodes, that's neither here nor there. While octal's
nice for decoding moves, it's less of an issue for conditionals. There's
still a very recognizable pattern:
JNZ = C2
JZ = CA
CNZ = C4
CZ = CC
RNZ = C0
RZ = C8
JNC = D2
JC = DA
CNC = D4
CC = DC
...
Cheers,
Chuck