Jtag timers and UART problem

Development Boards MicroMod
1

Hi!

I have a problem with Olimex JTAG, UART and Timers. When I disconnect JTAG everything works fine and I can use the UART and Timers, but when i debug with JTAG (or the JTAG i physically connected) and click “GO” only junk characters are transmitted. (It’s not enough to stop debugging. I have to remove the cable)

I have an RC servo controlled with PWM, and it only works if I disconnect the JTAG.

What is wrong?

I use a Atmega32 and tried with different boards and different JTAGs.

I tried with internal 1 mhz and external 4 Mhz crystal (15pF).

2

hi,

JTAG should not affect your baudrate (baudrate change should cause the junk characters), try to use crystal with less error in baudrate settings like 3.6864 Mhz

Best regards

Tsvetan

3

Hi!

But everything works great when the JTAG i disconnected, and when I make a reset after starting Debug. It’s not only UART, it is all timers…

I guess that reset solves the problem, but its a bit annoying.