I’ve been using openOCD and the Olimex USB JTAG pod for a couple months now. It has been working great.
I’m programming an Olimex LPC2148 processor on a simple header board. I was powering said board via the USB cable. Everything worked fine.
Now I am powering the board by applying 5VDC straight from a LM7805 ot the Vin pin on the header connector. I am not using the USB cable at all. I cannot program the micro controller anymore.
The message I get is:
Info: openocd.c:84 main(): Open On-Chip Debugger (2006-11-22 14:00 CEST)
Error: jtag.c:1156 jtag_validate_chain(): Error validating JTAG scan chain, IR mismatch, scan returned 0x00
I checked the schematics and it appears to me it should work just fine. The 5VDC from the LM7805 feeds directly into an LM1117. I’ve checked the processor voltage and its 3.0V, just like it was before.
Why can’t I program my LPC2148 with the new power supply ?
Thanks.