Started by iewgnip January 12, 2004
Hi All,

I hope you can help me with this problem. I have built my own EVB
and I have one that I got from Motorola as well (EVB DP256). The
Motorola EVB was working fine all this while with an 8Mhz crystal.
I used my own EVB to try to communicate with the Mot EVB using
BDM and was able to read/write contents into the device in the Mot
EVB (master-my EVB, target-Mot EVB). Great till here.
Then, I tried to download some code into RAM of the device in Mot
EVB and set the PC and then execute the BDM "GO". While doing all
this, I was scoping the BKGD pin (PT7 of master) of the Mot EVB to
make sure my timing comms were correct. However, after dumping this
code into RAM of the target, I can't seemed to view Flash and RAM
anymore. But when I reverted back to the previous code, it was ok.
Also, right now, after trying to dump and run code in the target's
RAM on the Mot EVB, the Mot EVB is not able to communicate properly
with MCUEz. I keep getting a "Unable to establish proper
communications with target". It trys to re-sync with the computer but
always fails communication. Scoped ECLK and XTAL, all were fine.
Power pins were all fine too.
However, there are a few trials when i do get the Mot EVB to
communicate with the computer but when I try to download code into
RAM and execute it wouldn't work. When code is downloaded into Flash
($C000) then it works, I can step-thru,breakpoint and run.
If anyone could probably suggest what has gone wrong, I'll be
really glad.