Just a couple of quick questions about JTAG on the AVR series, specifically the mega128, and the Olimex USB JTAG ICE. I haven't used JTAG on AVR before.
- Any positive or negative comments on the AVR-USB-JTAG from Olimex vs. the JTAGICE from Atmel? It seems like the JTAGICE uses a higher-speed USB connection vs. serial emulation on the Olimex device, is that accurate?
- What do I do with pin 8 (nTRST) on the JTAG connector? Olimex's designs run this to a GPIO on the micro, but I don't see the reason for it. I also don't understand why Vref runs to the port, but that's a separate issue.
Thanks.