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rosco-m68k / rosco_m68k

Design, documentation and software for the Really Old School Computer (M68K)
https://rosco-m68k.com
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Null-terminated print traps should leave A1 pointing to the terminator #385

Closed roscopeco closed 7 months ago

roscopeco commented 11 months ago

In the interface reference docs, we state that the print traps leave A1 pointing to the null terminator.

This no longer appears to be the case, we save and restore that register in the trap code.

since this behaviour is useful, we should put it back as it was.

0xTJ commented 11 months ago

Is there a one of the implementation that's known not to do as it's documented? I've checked most of the functions printing functions and those seemed to match what's documented.

TRAP #14 uses A0 while TRAP #13 uses A1, so I could see if there was some confusion where the main system print traps save and restore A1. I might however have also just missed a spot where the behaviour is wrong.

roscopeco commented 7 months ago

Closing this as superseded. If still an issue we can reopen or reraise 🙂