RE: [avr-chat] Pin Change Interrupts and UART on Mega88

[Alex Shepherd]

> The attiny26 datasheet specifically mentions that the pin 
> change interrupt is disabled when an "alternate function" is 
> enabled. I couldn't find anything similar in the atmega88 
> datasheet though. You may just have to try it out.

Yes I read something to this effect in an app note about using the USI
interface to emulate a UART. They used the pin change interrupt to detect
the start bit and then turned on the USI to handle the rest of the byte and
said that enabling the USI would disable the pin change interrupt.

I guess in my case I could enable the pin change interrupt to detect the
start bit edge and then enable the USART hopefully the time between
receiving the interrupt and enabling the USART would not interfere with the
normal USART reception.

Guess I'll have to give it a try.

Alex