I'm looking for the documented rise times on AVR general purpose port pins. As an example, in the ATMega644 datasheeet, I've found rise times documented for External Clock, TWI, and SPI pins. But, I can't find the rise time for general purpose port pins.
Perhaps it's documented and I'm not finding it. For example, I had done a fair bit of searching for the port pins' output impedance, but finally found that data in the I/O pin output voltage vs. source/sink current graphs.
Thanks for any help!