Hi all,
I'm now porting the redboot from a EVM board to my target board. However, I've changed the flash and it seems doesn't work with my old redboot configuration. I can only see the target board send some rubbish out from the serial port. I don't know what to do next. I'm actually loading the redboot thru a JTAG. In normal case, how does people solve this problem since it is tedious to trace the assembly from my windows based debugger?
Thanks, Eric
Probably a baud rate problem. Try various settings; 115k is now common, as are 57600 and 9600.
If fiddling around with the settings in your terminal program doesn't reveal anything, it's possible the serial port init is busted for your board, and you get to debug that.
Hi Watt,
Sorry, I did not describe the problem very clear. In fact, I know it is the flash problem because I can actually boot up the board when I remove the configuration of the flash I am using. When I just add the configuration of my flash, the output skew up and I don't know how to debug it. Do you know how can I check the problem in this stage?
Eric
14.9"
I don't know what you mean by "remove the configuration of the flash". Does that mean that you're restoring the old version of RedBoot? If so, it *still* sounds like a baud rate problem, since you probably have a different number compiled in. Or if you're restoring the RedBoot configuration partition, the one you program in isn't set up correctly for the RedBoot you're building.
If it's truly a problem with the flash load, I would be extremely surprised to see any noise at all out the serial port, as such fundamental problems tend to lock the processor up immediately.
eric enlightened us with:
I know this post is a few weeks old but I've only just seen it. In case you didn't work it out, there are two possibilities: redboot stores baud rate configuration information in the flash. If you can erase the flash entirely first, then RedBoot will pick up that it isn't initialised (a checksum failure) and will fall back to its default baud rate, whatever that is for your board.
The second possibility is that the data you are seeing goes something like $T02:12345678;fedcba98;656536565654#ab or whatever numbers. That's GDB remote protocol and means redboot has hit a processor exception for whatever reason and bombed out. One of the numbers will be the PC register in hex which you can look up in your redboot image or linker map, or you can attach with GDB to find out in a more friendly way where it stopped, assuming you have the source tree still around.
Jifl
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