keasley keasley

CWCF6.4 5828 fail to start

Discussion created by keasley keasley on Sep 7, 2007
Latest reply on Sep 11, 2007 by Dumitru Negrea
I have two prototype boards using the 5282. One starts as expected, but the other does not. We have reviewed connections, power, etc. and found no visible or measurable cause.

When the "bad" board powers up, I can connect to it using the BDM -- but:
a) all the General Purpose registers value of 0x000... and they will not change.
b) all Supervisor Registers value of 0BADBAD0. They will change but seem to make no difference
c) other registers are "unavailable"

Pressing "Reset" does not help.
Entering the "reset" command causes to board to appear normal.
If in Internal Boot mode, I can enter "reset run" and hang it up again, then enter "reset" and correct it.
If in External Boot mode, "reset run" dumps the debug session and I have only recovered with power cycle.

The board design does not allow for booting to Single Chip mode; D19 is tied low and I can only toggle D18 (using a jumper).

Please advise what is likely to cause this. Thank you.