The board was working fine but all of the sudden I can't download any code on it from Keil. Whenever I try to download code on the board, I get
"Could not find Cortex-M device in the JTAG chain! Please check the JTAG cable and connection devices"
I tried a couple of different cables but didn't work. What can be causing the problem?
What JTAG pod are you using?
You mention a chip, the board it is on might be more enlightening?
Try using SWD mode rather than JTAG mode.
Thanks for replying! I'm sorry but I'm a beginner. I don't know what is JTAG pod. I am using a Tiva C launchpad. How can I enable SWD mode?
The JTAG pod, ie J-LINK, U-LINK, etc. What debugger is selected?
SWD/JTAG mode is frequently a setting available in the Debug Settings Option
If you have code that puts the core to sleep or disconnects/reconfigures the pins used by the debugger can prevent connection. Check Connect under Reset settings, or things you can do with your board/chip to put it in soft safe mode, or into a ROM Loader, rather than the code you previously loaded.
Stellaris ICDI debugger is selected. I tried the SWD but didn't work. How can I do that? "or things you can do with your board/chip to put it in soft safe mode, or into a ROM Loader, rather than the code you previously loaded."
Did you get anu documentation with your board?
Have you read the documentation for the processor, and then verified how the processor behaves at boot and cross-correlated this with straps or pin assignments on your board?
Suddenly I got the same problem with Tiva-C LaunchPad. Is there any answer?