AVR-Chat

John Samperi wrote:
> G'day
> 
> We I finally got my updated board with the M64 on
> Friday. Put it together and got it running with some
> simple code, USART0 and USART1 talking to 2 terminals
> and the mandatory flashing led. The led uses timer
> overflow 1 (4.095ms) and a register dec from 127 to
> give about .5 sec flashes in the int routine. The code
> was ported from another app using the m8. Here is the
> strange part. The led would flash 3 times correctly,
> the 4th ON time was about twice as long, it would then
> flash 5 times correctly, the 6th OFF time was about
> twice as long, it would then flash 6 times correctly,
> the 7th OFF time was about twice as long. It would then
> repeat the sequence! For 2 days!
> 
> This morning (+-6am) I felt the need for a jtagice
> (nope not expecting) but being Sunday morning no chance
> of getting one in a hurry...unless..look up bootleg info
> about jtagice, adatpt one of my DXIO-6 module which uses
> M8535 (pin compatible with m16) some veroboard and some
> connectors and voila, instant jtagice //BRAG MODE ON//
> It worked first go!//BRAG MODE still ON// :-)

Where do you get the firmware to turn a mega8535 into a jtagice?

> Meanwhile back at the range...something happened by enabling
> disabling OCD and JTAG on the M64. The LED now flashes correctly
> even without jtag or programmer plugged in i.e. as it should.
> The question remains: Why is it so! Why is the timer now working
> as it should? Anyone has any ideas? No I haven't changed anything
> in the code, just played around with the 'fully working' jtag.

Could have something to do with the setting that allows timers
to be stopped or run at full speed during jtag single-stepping.

> By the way Dave, I learned from your problems with the Int vectors
> last week and copied and pasted them directly from the M64 PDF
> into my code. :-))