Dear all,
I managed to build a minsoc with all the source code provided on my de2(ep2c35), and I established the adv_jtag_bridge successfully. After that, I use or32-elf-gdb download the uart.or32(minsoc/sw/uart/) program into the minsoc, it displayed some information about the sections and the address.
It seems all right.
But when I continue the process like below:
set $pc=0x100
c
it stoped. With no more information displayed.

I tried to observe the signal "cpu_stall", it is high when I download the program and turn down when I use continue(c) command.
I guess the problem is that, I can't change PC by GDB, and that means I can't send a data into or1200.
But I can send data to on-chip memory, since I have sucessfully download the program.

I wonder why this happen and what can I do.

Most thanks.

What you get when you try to read spr registers ? Can You modify them from gdb ? use this commands and paste some output from gdb here: info registers set spr

sorry, something bad happend to my post ...
commands are:
>info registers
>set spr [register name] [value]

Thank you for your replying. I did that as your advice, I use "set SYS.NPC 0x100" and "set SYS.NPC=0x100" to set it. But unforturnately, neither did work.

use:
spr npc 0x100

here's a good cheat sheet for gdb commands:
http://opencores.org/or1k/ORPSoC_Board_Software_Debugging#GDB_commands_table

Hello Panbin,

which version of GDB are you using? Is your computer terminal configured with the same baudrate as the firmware? Is the board pinout for the serial port correclty configured on the UCF file?

Regards,
Raul