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Adding a delay such as the 20ms one we have in AVR programmer's initialization routine is tricky without a word like TICKS. This implementation is highly inaccurate, but more accurate and reliable than a "ballpark" DO..LOOP...
14 lines
634 B
Plaintext
14 lines
634 B
Plaintext
STABLE ABI: As a compatible binary, this binary follows the
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same stable ABI as its z80 counterpart.
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PS CHECKS: Unlike z80 boot code, we don't check PS at each next
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call (we do check RS though). It is the responsibility of every
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native PSP-modifying word to call chkPS, . Also, chkPS, is a
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bit different than in z80: it is parametrizable. The idea is
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that we always call chkPS, before popping, telling the expected
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size of stack. This allows for some interesting optimization.
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For example, in SWAP, no need to pop, chkPS, then push, we can
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chkPS and then proceed to optimized swapping in PS.
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To assemble, load blocks 445 through 461
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