From bb2e0fc1fbe21b2ef4128fa666922df63768acd4 Mon Sep 17 00:00:00 2001 From: Nicolas Schodet Date: Thu, 1 Jul 2010 21:52:10 +0200 Subject: digital/dev2/doc: document dev2 usage, closes #132 --- digital/dev2/doc/gpio.txt | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 digital/dev2/doc/gpio.txt (limited to 'digital/dev2/doc/gpio.txt') diff --git a/digital/dev2/doc/gpio.txt b/digital/dev2/doc/gpio.txt new file mode 100644 index 00000000..1a8b478f --- /dev/null +++ b/digital/dev2/doc/gpio.txt @@ -0,0 +1,39 @@ +========================================== + 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. + -- cgit v1.2.3