[ECOS] GDB stubs in ROM?
Sarah A Bailey
Mon Sep 11 04:31:00 GMT 2006
I've been working on code that uses eCos on the LPC2148. My question
is fairly straightforward: Can I run GDB stubs if I build eCos in
The answer seems to be no so far, but I thought I'd double check with
other developers. I searched the internet and mailing lists for an
answer, but the best I could find was from the eCos mailing list.
It basically said it's fairly difficult, and requires hardware support
for hardware breakpoints.
I've tried compiling eCos with GDB stubs in ROM, but I cannot set
software or hardware breakpoints in the code. I also can't continue.
(gdb) set debug remote 1
(gdb) hbreak cyg_user_start
Hardware assisted breakpoint 1 at 0x5fc: file blinky.c, line 90.
Sending packet: $Z0,89fc,4#50...Ack
Packet Z0 (software-breakpoint) is NOT supported
Sending packet: $m89fc,4#07...Ack
Packet received: 0000a0e3
Sending packet: $X89fc,0:#28...Ack
Packet received: OK
binary downloading suppported by target
Sending packet: $X89fc,4:\001\000\237ï#bb...Ack
Packet received: E03
Sending packet: $Z1,5fc,4#15...Ack
Packet Z1 (hardware-breakpoint) is NOT supported
Cannot insert breakpoint -2.
Error accessing memory address 0x89fc: Input/output error.
Cannot insert hardware breakpoint 1.
Could not insert hardware breakpoints:
You may have requested too many hardware breakpoints/watchpoints.
0x89fc is the address of main(). I had to explicitly call
breakpoint() in order for the GDB stubs to work at all. If I didn't
explicitly call breakpoint(), the hardware wouldn't respond to any GDB
packets and CTRL-C would not stop the processor.
I'm planning on getting a JTAG tool, but I was hoping to get some work
done before it arrives. It would be difficult to debug without GDB.
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