Connecting with TTL serial

The chumby has a four-pin, 3v level TTL serial connection port running at 115.2 Kbps. You cannot just connect this to your computer's serial port, parallel port or USB port without a converter. We think the best way to connect is using an FTDI cable which can be easily modified.

Make the Cable

You must use a 3.3v logic level FTDI cable, look for the letters "3V3" or similar on the cable. We also suggest checking with a multimeter that the voltage on the logic pins (everything but Red) is no higher than 3.3V. 5V logic will damage the chumby board, and it would be a shame if it broke before you got to have some fun!

Also, make sure you have an adapter thats a cable, so that you can move around the pins.
Use tweezers to lift up the black connector tabs.
Then gently pull out the wires
Repeat!
Rearrange the wires as shown, so you have Black (GND) then a space, Orange (TX) and Yellow (RX). You can clip the unused pins or cover them with heatshrink. They wont be used. Just make sure you don't have the conductive pins accidentally touch your Hacker Board!!!

Connect

Plug in your FTDI cable, and install any drivers. See our instructions for driver installation for Windows, Mac and Linux.

Once the driver is installed, verify the COM or tty port. For example, the COM port for our FTDI cable is COM34 (we have a lot of FTDI cables!). Open up a Serial Terminal program and connect to that COM or tty port at 115.2Kbps without hardware handshaking.
Connect a 5V regulated supply into the chumby and your FTDI cable so that the black wire lines up with the GND labeled pin.
You should see the following on your terminal:
Hit return a few times to get the shell!
This guide was first published on Dec 12, 2012. It was last updated on Dec 12, 2012. This page (Connecting with TTL serial) was last updated on Dec 05, 2019.