read NZ rotary dial's input from a retro phone using raspberry pi
reverse arranged dial in NZ
| Dial | Pi |
|---|---|
| 4 | GND |
| 5 | GPIO16 |
| 3 | GPIO20 |
| while dialing, p5 will toggle until the dial back to its home position |
p5: __________--------------------------------------------------------------------------------_______________
p3: _________________________________________--------___-------___--------___-------___-------_______________
| when released, the rotary dial will start rotating back |
| and sending pulses to p3 on its way back |
| this piece in p3 is the signal to be |
| processed and read the number from |
input_number = 10 - pulse_count
use argument -f to freeze the signal
| file | |
|---|---|
| v1.py | only 2 wires connect to port 4 and 5, can just read the number but not robust |
| v2.py | 3 wires version, the proper way of connection |
| read_gpio.py | visualise gpio input, read from GND by default for debugging. use -p port_number to select port, use -l set port to PUD_DOWN which is PUD_UP by default |
reading interval is set to 0.01s
-------___--------__--------___--------__--------___-------___--------___-------___--------___------
Number: 0
--------__--------__--------___--------___-------___--------__--------___-------___-------
Number: 1
--------___--------__--------___-------___--------___-------___--------__-------
Number: 2
--------__--------___-------___--------___-------___--------___------
Number: 3
--------___--------___-------___--------__--------___-------
Number: 4
--------___-------___--------___-------___-------
Number: 5
--------___-------___--------__-------
Number: 6
--------__--------___-------
Number: 7
--------__-------
Number: 8
-------
Number: 9