Objective Development Forums

Hi,

when looking at the ISP parts for example in the circuit for PowerSwitch I see that Pin 8 and 10 of the ISP connector are connected to PD0 and PD1 and thus to ground.
What is the meaning of doing this?

Since it's not necessary to have four ground pins, I usually connect two of them to RxD and TxD for debugging purposes. AVR-Doper can even read the debug info from these pins.

If you use AVR-Doper for In System Programming, you can print debug info through the ISP cable and AVR-Doper.

The additional resistor limits the current if a programmer with four ground pins is connected.