mio.py is “my” io library for Raspberry Pi. At present it is a kind of “hello world” program that demonstrates how work with one digital input, e.g., a switch, and one digital output, e.g., an LED. Below are (a) a photo of the Raspberry rigged up with a circuit managed by miO, (b) a description of the package, (c) some output on the command line, (d) a circuit diagram.

The (Python) code is at github.

(a) MIO RUNNING ON PI

(b) MIO: COMMAND SUMMARY

Suppose that LED is pin 17 and SWITCH is pin 23:

• blink(LED, 0.1, 0.3) — blink LED, on for 0.1 second, off for 0.3 seconds
• read(SWTICH) — read SWITCH: print 1 ON the first time it is closed, then the time it was held closed when it opens, then print 2 ON when it is closed the second time, etc.
• control(LED, SWITCH) — control LED with SWITCH. This function is like read, except that the LED blinks when the switch is closed.

These functions can be invoked fromt the command line: (a) sudo python mio.py blink, (b) sudo python mio.py read, (c) sudo python mio.py control.

(c) SOME OUTPUT

pi@raspberrypi ~/gpio $ sudo python3 mio.py read
    1 ON
      1.09
    2 ON
      1.75
    3 ON
      0.13
    4 ON
      0.11

(d) CIRCUIT DIAGRAM

Let the switch have terminals A and B.

   A --- 3.3V

              |--- 1K resistor --- Pin 23
   B --- T ---|
              |--- 10K resistor ---GND

   Pin 17 --- LED --- 330 Ohm resistor --- GND