What's the matter with the COP?

[wangbo]

I design a board with MPC8548E,and design the JTAG interface as the MPC8548EEC suggested,when I used the codewarrier to connect the board,it is failed and report " cannot reset the targets",if not chose the "Reset target On launch",it can connect to the board.I check out the signal "HRESET",and find it is asserted at the end of the process.my codewarrier and simulator all work well.so what's wrong with my board,thx.

[genuap]

Have you looked at JTAG TRST? This should be ANDED with POR. I believe there's a diagram in the HW spec or checklist that shows how to do this.

[wangbo]

yes,I'm sure that TRST is ANDED with POR.I compare it to a 8349 board,and find that TRST on 8349board is pull down by a 1k res,and the 8548e HW SPEC do not use any pull up or pull down res,is it correct?