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collapseos/blk/328

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z80: Use BC as IP register instead of IY It's a bit more inconvenient in terms of register protection (BC is much more generally useful than IY), but it makes tight spots such as next and execute much faster, so I think it's worth it.
2020-07-07 13:31:00 +10:00
CODE S= EXX, ( protect BC )
z80a: make mnemonic names more uniform across assemblers Initially, I used the same letters as those used in the z80 ref docs, but it makes the different assemblers harder to use than they should. Having consistent "argtype" rules across assemblers should help.
2020-06-28 12:01:56 +10:00
DE POP, HL POP, chkPS,
Make string length-prefixed instead of null-terminated I'm not sure why I chose null-terminated initially. Probably because the z80asm version had null-terminated strings. Length-prefixes strings are the traditional form of strings in Forth and it's a bit easier to work with them with traditional forth words when they're under this form.
2020-05-26 10:34:52 +10:00
LDA(DE),
(HL) CPr,
IFZ, ( same size? )
B A LDrr, ( loop A times )
BEGIN,
z80a: make mnemonic names more uniform across assemblers Initially, I used the same letters as those used in the z80 ref docs, but it makes the different assemblers harder to use than they should. Having consistent "argtype" rules across assemblers should help.
2020-06-28 12:01:56 +10:00
HL INCd, DE INCd,
Make string length-prefixed instead of null-terminated I'm not sure why I chose null-terminated initially. Probably because the z80asm version had null-terminated strings. Length-prefixes strings are the traditional form of strings in Forth and it's a bit easier to work with them with traditional forth words when they're under this form.
2020-05-26 10:34:52 +10:00
LDA(DE),
(HL) CPr,
JRNZ, BREAK, ( not equal? break early. NZ is set. )
DJNZ, AGAIN,
THEN,
Copy boot.z80 to blkfs
2020-04-23 11:19:12 +10:00
PUSHZ,
z80: Use BC as IP register instead of IY It's a bit more inconvenient in terms of register protection (BC is much more generally useful than IY), but it makes tight spots such as next and execute much faster, so I think it's worth it.
2020-07-07 13:31:00 +10:00
EXX, ( unprotect BC ) ;CODE