PocketC.H.I.P. Does Field Repair with C.H.I.P.py Ruxpin

CHIP in the Wild

Does a bear C.H.I.P. in the woods?

We were out in a field taking pictures of C.H.I.P.py Ruxpin –as you do when you have a C.H.I.P.-powered talking bear– and I wanted to get C.H.I.P.py to comment on the weather.

Lacking my laptop and with no clue of C.H.I.P.py’s IP address, what was I to do? Easy. Use three wires to directly connect C.H.I.P.py and PocketC.H.I.P.. With a few commands on PocketC.H.I.P., it’s easy to setup a connection and gain shell access to the bear (or any other device with exposed TX, RX, and ground). Here’s how I did it.

Parts

  • Three wires (18 AWG) – these don’t need to be fancy wires, but if you want to make them more robust, twist the wires using a drill, add header pins, and heatshrink tubing. Here are some great cable creation tips.

Tools

  • PocketC.H.I.P. – you could also use C.H.I.P. to connect to other devices using the same commands, however, since there’s no screen on C.H.I.P., I didn’t use it.

Connect to CHIPPY

1. Connect to target device

The connection between the two devices needs to share a ground wire and cross the TX and RX wires. The main reason I made this fancy wire is to have a cable with the TX and RX lines already crossed. This way I don’t have to think about wiring, I just make sure the ground pin is plugged into the proper pin.

Ground — Ground
TX — RX
RX — TX


CHIPpy Connected to PocketCHIP

2. PocketC.H.I.P. Setup

Power-on PocketC.H.I.P. and launch a terminal from the drop down menu.

sudo su

Stop the tty that’s running on /dev/ttyS0 using systemd.
systemctl stop serial-getty@ttyS0.service

Ensure the wires are connected correctly (something my fancy cable already takes care of), then grant permissions to root for PocketC.H.I.P.’s /dev/ttyS0.
chmod a+rw /dev/ttyS0

Connect to
cu -l /dev/ttyS0

To end the cu connection, simply type ~. and the connection will terminal.

Note: Learn more about cu here.


This method is great for more than just talking bears! When I need to setup a C.H.I.P. and don’t want to lug out a monitor and keyboard this is my default approach. Best of all, this trick works for any computer or device that exposes Ground, TX, and RX pins and has a UART. So the next time you need to access an unconfigured device, grab three wires and PocketC.H.I.P.!

CHIPpy Header

Posing with PocketC.H.I.P.

About the Author

Posted by

I'm busy writing and editing content at Next Thing Co.

Categories:

PocketC.H.I.P.