8-bit acorn hardware • Re: PS/2 interface for the Joystick port

... Conventionally, your interception is fine to also use &EF/&F0/&F1 for the same purpose, plus also PHP/SEI....PLP. Saves you two zero page locations for the control block pointer.
...
While you have IRQs off you also have access to IRQWS1 and IRQWS2 at &FA/&FB.

Thanks, I can't think of another place or person where you could get this information

And thanks for the IRQWS1/2 tip as I do need a couple of pairs of zp pointers for the relocation code which I run with PHP : SEI... PLP anyway as I am patching the osword and osbyte vectors in the same code.

I guess for chaining with extended vectors you could fall back to trampolining through your workspace if you have any.

Statistics: Posted by tricky — Mon Dec 09, 2024 4:54 pm

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