Given that every ATTiny connected already has a bootloader (micronucleus) installed, here's my theoretical chain:
Computer > Master ATTiny (Connected via USB) > ATTiny Slave A > ATTiny Slave B
Is it possible to flash an individual slave (say, slave B) with new software without replicating it to all of the other slaves, or altering the master?
Can this be done with the normal MISO/MOSI/SCK/RESET method?
I've done some research (Programming multiple ATMegas/Arduinos at once) but I'm not looking for a batch flashing method; I want to upload custom programming to a single slave.
Note: I'm not trying to pass data between the master and the slaves. What I want is to reprogram the slaves from a single USB connection. It's also important that each slave has a fixed identity so I know exactly which one I'm flashing every time I boot the "system".
Disclosure: I'm an arduino novice and programming intermediate. This is my first project utilizing serial communication.