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==========================================
 dev2 gpio - General Purpose Input Output
==========================================

The gpio module provides eight I/O to be controlled by the host.

Do not forget to select an output using the control script!

Controlling ouput
=================

Use the control script to set outputs and directions.

 dev2ctl.py --gpio *DDR* *PORT*

DDR and PORT have the same meaning as the corresponding AVR registers.  Each
parameter is an eight bit value, with each bit corresponding to one I/O port.

 - if DDR bit is 0, corresponding port is an input, use PORT to activate a
   pull-up,
 - if DDR bit is 1, corresponding port is an output, use PORT to select the
   output value.

For example:

 dev2ctl.py --gpio 0xc 0xa

 - ports 0, 4, 5, 6, 7 will be input with no pull-up,
 - port 1 will be input with pull-up,
 - port 2 will be output with value 0,
 - port 3 will be output with value 1.

Reading input
=============

To read inputs, use a serial monitor (minicom, picocom, gtkterm, screen,
socat...).  For each character sent to the console, input port current state
will be echoed back.