Timer Interrupt?

potatohead

Right now, I'm sifting through our threads to find the interrupt discussion. Thought I bookmarked it, but apparently didn't.

Anyone testing this?

I'm starting to work on an interrupt frame work for a video signal.

Seairth

(typing on phone, so being brief...)

Use ADDCNT to set the timer counter. Use WAITCNT to stall (SETQ with WC for timeout) or POLLCNT to poll.

To set the ISR:

mov ijmp1, #isr
setint1 #1

(Edit: corrected SETCNT to ADDCNT.)

ozpropdev

potatohead wrote: »

Right now, I'm sifting through our threads to find the interrupt discussion. Thought I bookmarked it, but apparently didn't.

Anyone testing this?

I'm starting to work on an interrupt frame work for a video signal.

Same here. Can't seem to find any interrupt info. Search is frustrating.
Hard to test without some clues to get started

potatohead

I got it!

This worked for me:

dat
		orgh	0


		org
		jmp	#init		'make sure to run in COG mode.

init		getcnt	temp
		addcnt	temp, ##$ffff		'set timer for lots of cycles
		setint1 #%001		'set timer mode
		mov	$1f4, #isr1	'set ISR address

loop		setxdac	dwhite
		jmp	#loop



isr1		getcnt	temp
		addcnt	temp, #100		'timer period
		setxdac	dblank
		reti1

potatohead

I don't think the getcnt in the ISR is needed.

ozpropdev

I found tis
http://forums.parallax.com/discussion/comment/1338752/#Comment_1338752

Seairth

potatohead wrote: »

I don't think the getcnt in the ISR is needed.

That depends on if you are setting the next interval from the beginning of the interrupt or not-the-beginning.

potatohead

True. Just figured that out when playing with a few scenarios. It's like "mark time" then work from there.

Seairth

Also, I would suggest seeing the ISR before setint1. And the assembler has predefined labels: ijmp1, ijmp2, ijmp3.

potatohead

Didn't know about the labels. Of course, good call on the order of things.

I've got enough to make a signal that should tolerate some pixel experiments now.