Re: Timer interrupt frequency (50Hz vs 60 Hz)
RETRO Innovations via Coco <coco-uNHYcr1XS/wmlAP/[email protected]>
| Newsgroups | gmane.comp.hardware.tandy.coco |
|---|---|
| Message-ID | <[email protected]> |
On 3/20/2025 7:07 PM, Alex Evans via Coco wrote: > Yes, you can interrupt (IRQ) on hsync on any coco. So if you write: prep: //put 0 in NUM // put 0 in START //enable fsync // wait for START to equal 2 // use NUM value to calc PAL or NTSC fsync_IRQ // increment START // if START = 1 // zero out NUM, enable hsync, and return // else disable fsync and hsync and return hsync_IRQ: // increment NUM // return Would the above give you different numbers in NUM you could use to determine PAL/NTSC? Jim -- RETRO Innovations, Contemporary Gear for Classic Systems www.go4retro.com store.go4retro.com -- Coco mailing list Coco-uNHYcr1XS/wmlAP/[email protected] https://pairlist5.pair.net/mailman/listinfo/coco