Here’s how to make a serial cable to control a Roomba with your Mac/PC. iRobot Roomba manufactured after October 2005 contain an electronic and software interface that allows you to control or modify Roomba’s behavior and remotely monitor its sensors. This interface is called the Roomba Serial Control Interface or Roomba SCI.
The Roomba SCI is a serial interface protocol to let you control your Roomba, but the port on the Roomba doesn’t conform to RS232 standards. This board does the conversion.
There are two boards shown here. The first version (larger, encased in lexan), and the second version (smaller, encased in a blue floss box).
Circuit is simply a 7805 +5V voltage regulator and MAX232 RS-232 transceiver, appropriate capacitors to make it work and a ‘power on’ LED. Because everything needs an LED. Flickr photo with notes here.
Below are parts lists from Jameco (and one from Radio Shack). Jameco doesn’t have the cheapest parts, but they do have an easy-to-use site, ship fast, and carry just about everything that a weekend electronics geek would need. If you want to really scrimp, shop at Digikey or Mouser, and you’ll probably save a few bucks on these parts.
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