XC888 JTAG disabled by default?

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
User20995
Level 1
Level 1
Hello all,

I want to flash the uC via JTAG, but I am not able to do it. I normally use XC888CM-8FF and I have no problems downloading it, but with this new uC, my IDE does not detect JTAG communication. It does not even read the JTAG ID.
I use Keil uVision v9.60 and ULINK2 Tool, and the JTAG hardware is the same we have been using for years in many different PCBs and it has always worked. (fyi we use JTAG default port P0.0-P0.1-P0.2, TMS, MBC & REST pins of the uC).
We normally use CAN BSL in production and JTAG in development, but since there are allocations issues with XC888CM we moved to CLM and therefore we lost the CAN BSL.

Can anyone give me some guidelines on what could be happening?
Is the JTAG port enabled by default when the uC is brand new?
May the flash be protected and therefore the JTAG disabled? In this case, how can I unprotect it using only JTAG?

Is there any test I could do to be sure that the uC is, at least, powered on and 'alive'?

Thanks in advance!
0 Likes
0 Replies