usb-icp and lpc934

[DaveA75]

I'm trying to connect to a 89lpc934 via the ISP header and the Future Design USB-ICP.  I keep getting the message:

"The device signature does not match the xpected values. Accessing a device using the wrong protocol could render the device unusable."

I've installed the latest drivers and the latest version of Flash Magic.  The microcontroller has never been used before so it's in the default factory state.  Can anyone help?

[Andy Ayre]

If you go to ISP -> Read Device Signature, what do you get?

[DaveA75]

FF for all three fields

[Andy Ayre]

That means the ICP isn't working. I would double-check your target circuit to make sure it meets the requirements for the USB-ICP.

[DaveA75]

Further reading indicates that the usb-icp needs to be able to control the uP power supply, with a maximum of 500pF of bypass capacitance.  Is this true?  This essentially makes the in-system programming useless if the target is in a system with other devices on the same power supply and the requisite bypass caps.....

[Andy Ayre]

I don't know - I'm not familiar with how the USB-ICP is implemented. In the case of the USB-ICP and the Philips ICP bridge, a microcontroller is controlling the ICP signals and their timing, not Flash Magic.

[Gabe]

One suggestion is to double check that the pins are correct on your target board.  Pins 2 and 4 were a little confusing to me when I first looked into this part.  Pin 4 has to go directly to the micro's power line with no other connections to it.  Pin 2 is jumpered to pin 4 during normal operation to power the board using whatever regulator and capacitance you have on the board.  

I ended up not going with the FDI programmer because having to the jumper for the micro's power was undesirable.

[DaveA75]

Does this mean that the programmer needs power supplied on pin2?  This wouldn't make any sense to me as the cable I got with the programmer has no connection to pin 2.

What in-circuit programming solution did you use instead?