collapseos/blk/007
Virgil Dupras de7cb4a80f Add word A,
This would be useful, for example, to allow the assembler to write
straight to an AT28 EEPROM without going to RAM. This would be a
life saver in machines with tight RAM such as the SMS.
2020-10-28 20:45:50 -04:00

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( Splits word into msb/lsb, lsb being on TOS )
: SPLITB
256 /MOD SWAP
;
: PC H@ ORG @ - BIN( @ + ;
( A, spits an assembled byte, A,, spits an assembled word
Both increase PC. )
: A,, SPLITB A, A, ;
: <<3 3 LSHIFT ; : <<4 4 LSHIFT ;
( As a general rule, IX and IY are equivalent to spitting an
extra 0xdd / 0xfd and then spit the equivalent of HL )
: IX 0xdd A, HL ; : IY 0xfd A, HL ;
: _ix+- 0xff AND 0xdd A, (HL) ;
: _iy+- 0xff AND 0xfd A, (HL) ;
: IX+ _ix+- ; : IX- 0 -^ _ix+- ;
: IY+ _iy+- ; : IY- 0 -^ _iy+- ;