Saturday, July 12, 2008

Missing EEPROM on OpenOCD-USB Adapter board

As it turned out OpenOCD-USB Adapter does not have EEPROM which is on the adapter schematic (see the bottom of this page). The EEPROM chip (93LC46BT SOT-23-6) was removed from the board after manufacturing. It is clearly can be seen on the picture (6 pads on the right of USB connector). I guess, the EEPROM chip was removed because of an error on the adapter PCB (EEPROM's CLK and Vcc pins are swapped). The same adapter is also available form So be aware of this defect.


Anonymous said...

What version of the OpenOCD-USB board do you have?
I've got a "625000043A", which does have the EEPROM fitted, but which currently does not enumerate on any machine I have connected it to. The only schematic I have seen is for 61000043A :-(

Misha said...

What version of the OpenOCD-USB board do you have?
The number on the back of PCB is 625000043A.
As I mentioned in another post the device is functional. I am using the adapter with my Mac to upload a firmware and debug code on LPC2103 and LPC2148.

Anonymous said...

Thanks for the info.
I got my board from , and it did have the EEPROM fitted. However, it would not connect to my Mac or Linux machines.
The PCB is the same number as yours, and I confirmed it has the same layout error (swapped clk and vcc).
When I removed the EEPROM, the board is now detected by the USB subsystem under Linux and MacOS.
I'm currently trying to connect from a Debian linux machine to an LM3S6965 evaluation board. Once it is working, I'll be trying other CortexM devices, and trying with MacOSX.