Teletext Experimenter’s Board

A Teletext decoder and RGB display board based around the Philips SAA5246 Teletext decoder IC. This board can:

  • Decode teletext from a composite-video carrier
  • Display it on an RGB monitor
  • Allow you to read a decoded page back to your host device
  • Allow you to substitute your own page data, making a “teletext quality” graphics card
  • Be controlled entirely via I2C!

Requirements

This board can do nothing on its own – it needs some sort of computer or microcontroller to be told what to do. This microcontroller needs to support I2C – like the Arduino, Raspberry-Pi, PIC micros, Acorn Archimedes, and many others.

You need to be comfortable with soldering and enjoy amateur digital electronics as a hobby in order to make use of it. If you’re not sure, I’d advise you to read through all the pages here (including the tutorials) and see how much of it is familiar to you.

In Action

This is it decoding the Teletext stream from a Raspberry-Pi running vbit2, and displaying it on a spare monitor. The Teletext Experimenter’s Board os being controlled by an Arduino Uno here, running the code featured in Tutorial 3. And yes, I was working on this on New Year’s Eve. Don’t judge me. Rum-and-Teletext makes for a better New-Year’s-Eve than watching Jools Holland:

This is a simple prototype clock. It’s running on an Arduino Uno with a DS1307 RTC module. The digits came from a bitmap font, and the date is double-height text:

And this is a video of my Teletext fishtank, being driven by a Raspberry-Pi. Coder-art for the win:

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