Programming AVRs with AVRISP when using the SPI bus at the same time?

Hi

I would like to ask a question because i would like to make sure before i try. I currently using a AVRISP programmer from Atmel which uses the SPI to program the AVR. And i want to also use the SPI for communication with a SD Card. I am wondering if there could be an issue. Because one of my friends that have the same programmer was using the programmer and EEPROM through the SPI and something has cooked his programmer. Would there be any electrical issues with both these devices connected to the same pins? Should there be some inline resisters?

I would just like to know if anyone knows about this before i go trying what i intend to do.

Thanks for your help

Scotty

Reply to
Scotty
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I'm using exactly the same configuration with simple resistor interface to the SD (MMC) card. I don't see what problem it could cause. The SD card is deselected while you program the AVR.

Reply to
larwe

Thanks

I just wanted to make sure as i did not really want to distroy my programmer.

Scotty

Reply to
Scotty

Be careful of target vs. program cable power. I tend to leave the Vcc line disconnected on my ISP connector. When I'm laying out a PCB with ISP, I put a zero ohm resistor on that line, and don't normally stuff it. That way the board won't be powered by the debugger, and the debugger won't fight the board's PSU.

Reply to
larwe

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