[avr-chat] avr-gdb, assembly, and JTAG

[Marge Coahran]

Can avr-gdb/avarice be used with source written in assembly (eg, can gdb 
display values stored in specific registers)? The code would be assembled 
with avra.

Also, do I understand correctly that to use JTAG in a Linux environment, I 
first need to use ISP once to enable the JTAGEN fuse, but thereafter the 
fuse can remain enabled over a sequence of program and debug sessions?

For context, I teach a course in Computer Organization and Architecture 
using the AVR, and I specifically want students to work in assembly for 
the insight it gives into the inner workings of the processor. I have a 
set of STK500's and Dragons for this. I currently have Atmega8515L chips 
that came with the STK500's, but I am considering moving to ATmega16L 
for JTAG support. (I think debugWIRE is probably not feasible for this 
because, if I understand correctly, in Linux it requires using HV 
programming to disable the DWEN fuse between each debug and program 
operation. But HV and ISP/ICE need different physical connections on the 
STK500, and I don't trust every student to do this correctly every time. I 
think it would result in fried boards.)

Thanks,
Marge Coahran
Computer Science
Grinnell College