Quick Guide to Connecting your Raspberry Pi to Arduino via USB Cable
There are several ways you can have serial transmission between your Raspberry Pi and your Arduino board – this is one of the laziest. Quick background – I have a buggy I want to control from the Pi using the Arduino board for sensors and relays. The Pi fitted with this cheap wireless adapter works perfectly.
Step 1: Shut off all Serial Action going on with the Pi.
You have to edit two places. The first ‘/boot/cmdline.txt’ – delete
Then bounce over to /etc/inittab and we have to comment out the last line by adding the # to the beginning.
#T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100
Step 2: Reboot with your Arduino plugged in and make sure you have the proper power.
Step 3: Download a serial terminal like minicom or cu. I like cu.
sudo apt-get install cu
Step 4: Figure out where your Arduino can be accessed. (Also make sure that you have already uploaded a script that is waiting for a serial connection.) Most likely as a Raspberry Pi user it will be ‘/dev/ttyACM0’ but to be sure I did a quick ‘ls -l /etc/serial/by-path’ and got the following answer:
lrwxrwxrwx 1 root root 13 Dec 31 1969 platform-bcm2708_usb-usb-0:1.2:1.0 -> ../../ttyACM0
Step 5: Enjoy the magic of sending bits over the wire. Connect with your serial terminal client – in my case:
cu -l /dev/ttyACM0 -s 9600
and you should see a connected message.
Step 6: Figure out what you are going to do with this new serial knowledge.