2020-06-13 04:01:24 +10:00
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PC/AT Recipe
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Work in progress.
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2020-06-17 09:05:36 +10:00
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Register usage: SP is PSP, BP is RSP, DX is IP
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2020-06-22 04:07:02 +10:00
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Unlike z80 boot code, we don't check PS at each next call (we
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do check RS though). It is the responsibility of every native
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PSP-modifying word to call chkPS, . Also, chkPS, is a bit
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different than in z80: it is parametrizable. The idea is that
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we always call chkPS, before popping, telling the expected size
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of stack. This allows for some interesting optimization. For
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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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811 MBR bootloader 812-829 Boot code
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