I have a few boards with an LPC1817 on which the JTAG is no longer working.
I have checked all the conditions that may disable the JTAG.
- Pin 28 DBGEN is not connected and pulled up internally
- OTP bank 3 is not progammed
- The CRP is not active
- CREG5 is not loaded
Can anybody give me a hint why the JTAG stops working.
I have connected both LPC-Link2 and J-LinkPro without success.
I can only program through ISP.
Regards,
Jos
Hi Jos,
sometimes SWD ist still working when JTAG is not.So make a crosscheck.
Reason could be a damage of one of the JTAG inputs. See this thread for more details:
https://community.nxp.com/thread/487475
Regards,
Bernhard.
Thanks Bernhard,
We will have a closer look at the connection sequence and grounding of power and jtag at our production facility.
Regards,
Jos