I want to make an Attiny programmer as an Arduino (Uno) shield. I know that some Attiny programmers already exits but I'm trying to make something different that will meet my needs better.
My question is related to the 10uf capacitor used between the GND and the RESET pin of Arduino. I understood that it is needed to prevent the reset of Arduino.
I was wandering if is it possible that, in some cases, the programming of Attiny may not work because of this capacitor?
Has anyone experienced such thing?
An option would be to add a jumper to disable the capacitor if required, but I want to keep the board as simple as possible so I wouldn’t add a jumper if it isn’t absolutely needed.
ktor:
My question is related to the 10uf capacitor used between the GND and the RESET pin of Arduino. I understood that it is needed to prevent the reset of Arduino.
That is correct - once the "Arduino as programmer" sketch is loaded and running, it does not want to be reset as the IDE opens the serial (USB) port to communicate with it.
ktor:
I was wondering if is it possible that, in some cases, the programming of Attiny may not work because of this capacitor?
Has anyone experienced such thing?
The capacitor is not connected to the ATtiny in any way. Why would this be of relevance? The programming connections for the ATtiny are taken from the ICSP connector except for the reset pin, which is taken from a port pin. You are using an adaptor cable specially wired to do this, as in Nick's tuorial.