[Coco] replacing main rom

[John R. Hogerhuis]

On Tue, 2005-05-10 at 13:28 -0700, John Hogerhuis wrote:
> I've been reading through the super extended color basic manual to
> figure out what needs to be set up on the coco at startup.
> 

err, hmm, I meant the super ECB unravelled book. The manual ain't much
good for this kinda thing...

Anyway I guess there's nothing Free around... to start I just need to
write the minimal code to come up in 80-column hardware text screen. For
now I can just poll the keyboard eventually though I will start adding
interrupt handlers.

Are there any interrupts that the coco must service for it to function
normally?

Looking at SEBU (super extended basic unravelled) I see

TMR Timer interrupt
HBORD Horizontal border interrupt
VBORD Vertical border interrupt
EI2 Serial border interrupt
EI1 Keyboard interrupt
EI0 Cartridge interrupt

I'm thinking the GIME doesn't need any help to run the display, so I
don't need to do anything special (other than return from interrupt) on
HBORD and VBORD, right? 

-- John.