I am having multiple random errors when trying to download/debug using uVision4 and the ULink or ULink Pro JTAG units on a CortexM3 target. On good days, it actually programs flash and runs. That's very rare. On most days, I get these errors in random order:
"No ULINK device found" "No JTAG Device Found" "Too Many Devices in JTAG Scan Chain"
I really like that last one because after that uVision locks up completely and I have to reboot my PC. I am running Windows XP. Anyone have similar issues? Is there a way to fix this?
I've tried all of the Debug settings. In the Debug settings panel, it usually shows the correct JTAG target device, although sometimes it shows no target device at all and I cannot get one to appear.
Hi Ken,
(Let me guess the LPC1788?)
I get these errors sometimes because the board is reset and there is no code at 0x00. Or more precisely the reset vectors aren't there or are corrupted.
Generally what I do is erase the flash with flash magic (http://www.flashmagictool.com/) and I'm back up and running.
Regards,
Marc
as far as the debugger locking up, unplugging the ulink2 from your computer usually restores control.
Which device are you using?
Is this a custom board you are debugging on? Is the board showing signs that it is running, or is it frozen.
If you go to project-> options for target -> Debug tab -> Settings button (on the right hand side)
Can you see the ULINK serial number?
Can you see your device's JTAG ID on the TDO row in on the right hand side.
If this is a Cortex device, have you tried using serial wire instead?