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.
For a custom made board, as a first step you must to be able to download and run a project using a board-specific init.cfg file. Furthermore, "Verify Memory Writes" must be checked in the project's CF Debugger Settings panel. Once the debugger can step and run through the main code on the board with Verify Memory Writes on, you can build the ROM version of the project and program the flash. You will have to write your own init.cfg file with a minimal register initialization to properly configure the board's CPU and peripherals on your custom board. For a starting point, you can study the init.cfg files from the CodeWarrior support directory (CodeWarrior for ColdFire V6.4 installation folder\E68K_Support\Initialization_Files). Make a copy of the init.cfg file that's the closest match to your board's hardware configuration and name it my_custom_board_init.cfg. Edit this file to match your board's settings (clocks, RAM, flash, register initialization, memory initialization, and so on) exactly. Now perform a Debug->Connect command with the modified init file selected. To have the Debugger use the modified file, in the CF Debugger Settings panel choose Use Target Initialization file and navigate to my_custom_board_init.cfg. Then (if your board's RAM was correctly initialized), you should be able to
perform debugging operations on the board.
The same board initialization has to be done in the stand-alone version of the project (ROM version), but from within source code. The my_custom_board_init.cfg file is only executed on the target board at the beginning of a debug session.
You can use the Hardware Diagnostics tool (CW menu Tools->Hardware Diagnostics) with your Target Processor, Connection, and my_custom_board_init.cfg file selected in the Hardware Diagnostics -> Configuration panel when testing RAM memory accesses on the board.
If you still need our help after these procedures, please log a service request here.