PLEASE HELP ME: background mode Problem

[bitasobhani]

Hi all

I cannot program 1321x SRB board by a BDM programmer when I use switching power supply (yellow led on programmer is OFF). But when I use USB supply it can be programmed (yellow led on programmer is ON). I have the same problem when programming 13192 SARD board whith switching power supply. Unfortunately the board has no USB connector. So I cannot program the board at all. 

I measured switching power supply voltage with voltmeter. It is 9.15volt.

Thanks

[peg]

Hello,

Does the SARD board work with a 9V battery?

Does the green power LED on the SARD come on with the external power supply like it does with the battery?

You do realise the power switch works opposite when using external power supply.

Can you measure 3 volts on the 2 pins behind the serial socket? (marked 3V and + -)

[bitasobhani · Accepted solution]

Thanks for reply

I solved the problem. It was due to disconnection of the board ground and programmer ground pin in flat cable. So when I used USB supply, the two groud was connected through the computer.