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17 lines
615 B
Plaintext
17 lines
615 B
Plaintext
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Z80 boot code
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This assembles the boot binary. It requires the Z80 assembler
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(B200) and cross compilation setup (B260).
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On top of that, it requires RAMSTART to be defined as the
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beginning address of RAM. This is where system variables are
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placed. HERE is then placed at RAM+80 (ref B80).
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We also need RS_ADDR to be set to the bottom address of the
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Return Stack.
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RESERVED REGISTERS: At all times, IX points to RSP TOS and IY
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is IP. SP points to PSP TOS, but you can still use the stack\
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in native code. you just have to make sure you've restored it
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before "next". (cont.)
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