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The SAA5244 is a complete teletext decoder chip with built-in single page memory. It was introduced in March 1996 and was used in TVs and, more recently, Nathan Dane's Teletext In Vison Decoder.


The SAA5244 decodes teletext to Level 1 specifications.

It can decode additional packets such as Packets 8/30 and 27, making it compatible with FASTEXT, BSDP and PDC. It also automatically decodes the Hamming 8/4 error protection on these packets.

It's available as a 40-pin DIP or 44-pin QFP and requires a 27MHz clock signal, which can be supplied by a standard crystal with additional circuitry or a crystal oscillator.

It comes with 5 national options (additional characters) built-in, English, German, Swedish, Italian and French - and also 32 characters for OSD use.

The SAA5244 can act as a master or slave for video sync - it can even sync to 525 line sources for stable text overlay.

The chip can be used as a simple display chip, by setting it to master sync mode and disabling the acquisition circuits you can write freely to any point on the 25 row, 40 column display.


The SAA5244 is programmed via its I2C bus similarly to many other such chips of the era - a guide to the programming can be found (link) or in its datasheet.


The SAA5244 takes a standard 625 line Composite PAL video signal as its video input. This connects to pin 8 (DIP) or 25 (QFP) via a decoupling ceramic capacitor.

It outputs an RGB video signal, whose voltage peak can be controlled by the RGBREF pin, along with a Blanking signal which can be used to overlay text on a live video signal - this requires a SCART socket or additional circuitry. In master sync mode it outputs a sync signal from pin 12 (DIP) or 29 (QFP). In slave mode this pin is used as a sync input.

Additionally, the chip outputs an Odd/Even field clock, Y (luma) and a "contrast reduction" output for overlay use.