Hi all
Hope someone can help me a bit. I can get the SWD to work, or partial at least. JTAG not at all
JTAG:
If I select JTAG as the interface in KEIL, the CPU can be detected and the interface. But I can't erase, program or debug. When I erase/program/debug I get "Cannot access memory" and a "Error: Flash Erase failed - Target Dll has been cancled"
I have tried lowing the clock with no luck.
I'm using the small 10 pin header from the ULINK2 as my JTAG connector. Pin 10 (RESET) is connected to the JTAG_TRST on the CPU. That may be wrong? Also there isn't a 100 k Ohm pull down on the JTAG_TCK. That my also be a problem. I will try correcting them and retry.
SWD: Targer CPU is detected and I can erase and download the flash. I then can start the debugger and run my code. The problem first occur when I stop the debugger. Then I can't erase, program or start debugging again. I need to get the CPU into the internal bootloader first, before I can reuse the SWD interface and re-programm and debug.
I have the idea, that this is because the JTAG interface isn't working correctly. Somehow it needs the JTAGbefore it can switch to SWD?
HARDWARE: It is a custom platform using a LPC1788 Cortex M3 and I use ULINK2 and the latest MDK-ARK uVision. Crystal speed at 12 MHz. Using a GPIO sample, from the CMSIS lib, for testing
Thomas