Hi guys,

I just bought another 2 atmegas and it seems to be just a pain trying to plug and replug my programming cable into each of the pins of the 2 microcontrollers. How do you guys deal with that and having to program 2 or more mcus? I was wondering if there was some kind of switch were I could have the programming cable hooked up to and I just have to turn it one way and it programs the master, and then I turn it the other way to program the slave. Or something similar to that.

-Dan

If you're not using both of those pins on both of the MCUs, you could connect either the TX's or the RX's together, and then use an SPDT switch (same kind as the programming switch) to switch the other wire between the two chips.

If you're using both pins on both chips, you can use a DPDT switch, but it's hard to find one with the 0.3" row spacing and 0.1" pin spacing for a breadboard. Otherwise you can use two SPDT switches, or four SPST switches (like the DIP switches that come with the Nerdkit) and just remember to switch them in pairs.

Thanks Bretm,

I'll give that a shot with the 2 spdt switches included with the nerdkit and hopefully it will help.

-Dan

I drew up a circuit, had PCBs manufactured, put the components on, including a header for the programming cable, and just swap MCUs out of it, so I never have to change the programming cable again.

BM