Rex Wasn’t Really A PDA, It Was The First Great Digital Rolodex

Back in the 1990s I was fascinated with small computers. I used the HP200LX palmtop computer for almost ten years, which I wrote about back in December. Naturally, the Franklin Rex 3 PCMCIA-sized organizer caught my attention when it was released in 1997. Here was a Personal Digital Assistant (PDA) the size of a credit card that could fit not just in your pocket, but in your shirt pocket.

Viewed today, it was an interesting paradigm. The screen takes up almost the entire front face of the device with a few buttons for navigation. But isn’t it a deal-breaker that you can’t enter or edit contact info on the device itself? This was long before cellphones were pervasive, and if you had the option to connect to the internet a telephone or Ethernet cable was involved. The ability to have a large data set in your pocket viewable without slapping a brick-like laptop on a table was pretty huge.

I think the killer feature was the PCMCIA interface. I challenged myself to reverse engineer the API so that I could sync data outside of the

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Rex, The ARM-Powered Robot Board


There are a million tutorials out there for building a robot with an Arduino or Raspberry Pi, but they all suffer from the same problem: neither the ‘duino nor the Raspi are fully integrated solutions that put all the hardware – battery connectors, I/O ports, and everything else on the same board. That’s the problem Rex, an ARM-powered robot controller, solves.

The specs for Rex include a 1GHz ARM Cortex-A8 with a Video SoC and DSP core, 512 MB of RAM, USB host port, support for a camera module, and 3.5mm jacks for stereo in and out. On top of that, there’s I2C expansion ports for a servo adapter and an input and output for a 6-12 V battery. Basically, the Rex is something akin to the Beaglebone Black with the hardware optimized for a robotic control system.

Because shipping an ARM board without any software would be rather dull, the guys behind Rex came up with Alphalem OS, a Linux distro that includes scripts, sample programs, and an API for interaction with I2C devices. Of course Rex will also run other robotics operating systems and the usual Debian/Ubuntu/Whathaveu distros.

It’s an impressive bit of hardware, capable of speech recognition, and machine vision tasks with OpenCV. Combine this with a whole bunch of servos, and Rex can easily become the brains of a nightmarish hexapod robot that responds to your voice and follows you around the room.

You can pick up a Rex over on the Kickstarter with delivery due sometime this summer.