jtag interface damaged or missing on LPC2378

I have two Olimex LPC-2378-STK boards.

Somehow the JTAG interface code was damaged on one board, probably from trying to download a Flash Debug program. On the other board, the LPC2378 chip was replaced because the original chip had a faulty TIMER0.

On either board, trying to load a Flash Debug program, I get

JTAG Error: No contact with the JTAG Interface

On retry, I get

JTAG Error: Unknown Fault - No valid response from target

On the board with the replaced LPC2378, a Ram Debug program loads and executes properly.

On the other board, a Ram Debug program gives:

Downloading and Verifying Application

On retry:

Warning: There were warnings during download, see Log Window

Warning: Target inconsistency detected in Memory range 0x00000000- 0x0000003B

Warning: Target inconsistency detected in Memory range 0x40000044- 0x40000C97

and the program goes into loop at Data abort. However, if I ground the ISP pin, this board loads and executes properly.

I suspect that the replacement LPC2378 was not programmed with the JTAG interface and that the on other board the JTAG interface was overwritten.

If the problem is missing or overwritten JTAG code, is there a way to restore it? Or is there another problem?

The JTAG interface cannot be overwritten, it’s implemented in hardware.

Leon

Leon,

Ok, thanks for that info.

More info:

I am using IAR Embedded Workbench with Macraigor driver and Wiggler OCD interface device.

Using Flash Magic I erased the flash memory in the board that was having problems with Ram Debug. Downloading Ram Debug programs now works fine on both boards.

I still cannot download Flash Debug on either board.

Is it possible that the boot loader has been corrupted? If so how can it be restored?

The boot loader can be corrupted. There have been several discussions about this on the Yahoo LPC2000 forum.

Leon