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440ea43a88
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.
13 lines
416 B
Plaintext
13 lines
416 B
Plaintext
lblchkPS BSET ( chkPS )
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( Note that you only need to call this in words that push
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back to PSP. If they don't, calling chkPS is redundant with
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check in next )
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EXX,
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( We have the return address for this very call on the stack
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and protected registers. 2- is to compensate that. )
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HL PS_ADDR 2- LDdn,
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SP SUBHLd,
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EXX,
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CNC RETc, ( PS_ADDR >= SP? good )
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JR, lblofl BWR ( abortUnderflow-B298 )
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