[Coco] OS-9 Level1 Version 02.00.00 FYI

[Walter Zambotti]

I have been continuing to find out why this version of OS9 won't run on (O)VCC.

The only interesting thing I have found is that this version does not seem to be generating any interrupts once it gets so far into the boot.

This explains why the keyboard isn’t working.

I can see it writes the value Cx (where x is any hex digit) to GIME reg 90 several times.  This would cause the chip IRQ output to be enabled.

However at no point is gime reg 92 (hex) (or 93) ever written to.  Which IRQ selection and request enable register.

So unless IRQs are meant to be enabled by default I'm not sure!

So not sure what magic is being employed on Lvl 1 Ver 2 to generate inerrupts.

Walte