I liked the simple elegance of my Really Simple Raspberry Pi internet radio that just had a push button to change the channel… but I saw this project that connected a RaspberryPi radio to an Arduino LCD shield for displaying station names and for controlling the radio with buttons.
I happen to have an unused Arduino Uno and LCD shield lying around, so I decided to have a go at this myself. My LCD is a different kind, so I had to change the code for my shield – it’s one of these: http://www.hobbytronics.co.uk/arduino-lcd-keypad-shield
The main steps were:
1) Install mpc & mpd, add 7 internet radio stations.
2) Install nanpy.
3) Add the code below.
So far my code only changes the channel up and down, next step is to do volume as well. I had to use a USB port to drive the display, so I’m back to using the Pi’s internal headphone jack rather than USB. It’s also not very stable – sometimes it is better to keep things simple. It’s usually fairly obvious which station you’re listening to, so does a radio need an LCD display?
Here’s my rough Python code. I called it lcd-soundsystem.py. Ahem.
#!/usr/bin/env python
import time
import os
from nanpy import Arduino
from nanpy import (Lcd)
Arduino.pinMode(0, input)
lcd = Lcd([8, 9, 4, 5, 6, 7], [16, 2])
lcd.printString("MyLittleRadio v1", 0, 0)
lcd.printString("by @blogmywiki ", 0, 1)
time.sleep(2)
def getKey():
val = Arduino.analogRead(0)
if val == 1023:
return "NONE"
elif val < 100:
return "RIGHT"
elif val < 200:
return "UP"
elif val < 400:
return "DOWN"
elif val < 600:
return "LEFT"
elif val < 800:
return "SEL"
else:
return "KBD_FAULT"
def getTrack():
L= [S.strip('\n') for S in os.popen('mpc').readlines()] # Get the Track info from the stdout of the mpc command
sttn = L[0][0:15] # Pick out the Station and Track info
lcd.printString(16*" ", 0, 0) # Send it out to the LCD Display
lcd.printString(sttn, 0, 0)
lcd.printString(16*" ", 0, 1)
print L
print sttn
station = 4
os.system("mpc play 4")
getTrack()
while True:
#take a reading
key=getKey()
if key == "UP":
station += 1
if station > 7:
station = 1
print(str(station))
os.system("mpc play " + str(station))
getTrack()
elif key == "DOWN":
station -=1
if station < 1:
station = 7
print(str(station))
os.system("mpc play " + str(station))
getTrack()
