Development Board HP-488 (Version 3?)

[Mark]

Hi Guys,

The MCLR Reset is not working on the board. the switch is fine but the board is not delivering 5v to the MCLR pin (on any socket). It seems to be not connected as some chips leak enough current to bring it up to around 3v in which case the chip works. Any suggestions? (J29 for Power/USB looks OK).

Where is R12 (the pull up resistor?) on the board, or is it not labelled?
Could you send a clear schematic of the board (the one on the data sheet is unclear) so I can try and diagnose the problem?

Thanks,

Mark

[Benj]

Hello Mark

The MCLR pullup resistor is 10K and labelled R34 (just above the ICD2 / USB jumpers) and connects to pin 13 of U3. I will private message you with a clearer schematic of the board.