I'm trying to use a Nano V3 clone as an ISP to program atmega328p's because I have not dedicated programmer yet. As part of troubleshooting I'm just trying to program another breakout board with ISP headers with something simple as the example Blink sketch. Everything seems to go fine as far:
- I can upload the programmer sketch to the programmer Nano
- The program is running fine with a pulsating heartbeat
- I can program the target breakout with the Blink sketch using Arduino IDE
However, here the bad stuff occurs - The programmer Nano ALSO turns into Blink:
I can actually workaround by just changing back to AVRISP mk2 and uploading the ArduinoISP sketch again and then the programmer Nano is an ISP programmer again and the other one still Blink. But it's just weird and I really don't want that as part of my workflow and maybe I have other issues due to this that I don't understand.
To be super clear on my setup:
- I'm on OSX, connecting a usb cable to a Nano V3 clone. I've uploaded the 'ArduinoISP' example sketch as of Arduino IDE 1.8.5 (I think it has been updated recently)
- The Nano seems is running this sketch - the heartbeat is pulsating
- I connect 5 of the 6 pins on ISP 1-1, everything but the reset which I connect from D10 on programmer to reset on ISP header of target - all according to instructions.
- I change the programmer in Arduino IDE to be 'Arduino as ISP' and leave everything else intact, port - same usb port, processor - still atmega328p, board - still arduino nano.
- upload Blink
This makes the programmer turn into Blink too.