Question
Port 1 on the ADuC834 is primarily used for analog inputs. Can I use Port 1
pins for digital I/0?
If so, how?
Answer
Pins 1.2 to P1.7 inclusive are analog input/digital input pins. They have no
digital output
capabilities. The default configuration for these six Port 1 pins is as analog
inputs. In the default
state, the Port 1 register contains FFh. To configure any of these six Port 1
pins as a digital input,
simply clear the corresponding bit to zero in the Port 1 register (P1).
P1.0 and P1.1 are digital I/O pins and have a pull-up configuration as
described in datasheet for Port 3.
Both P1.0 and P1.1 have an increased current sink capability of 10 mA.