All material on this page is contributed by Mr. Pascal Holdry, France. Mr. Holdry obtained permission to publish the documentation and firmware for non-commercial purposes.

µInflux HRC 80 High Resolution Color card for the TRS-80

The HRC 80 card is a graphical extension card for the TRS-80 and compatibles. It is based on the Texas Instruments TMS 3556 Video Display Processor and supports a 320x250 pixels in 8 colors or grey levels. The standard TRS-80 video screen could be superimposed to the graphics screen.

The TMS3556 has support for several teletext/videotext standards: Antiope, Ceefax, Prestel, Teletel. It has 512 characters split into four equal sized generators. Characters can be displayed at normal size, double height, double width or both. Foreground and background color are selectable out of a palet of eight (including black and white).

µInflux board

µInflux HRC 80 board

The board connected to the TRS-80 expansion board for programming and syncing with the TRS-80 screen. It was also connected to the video output so the TRS-80 text and graphics could be superimposed to the graphics. The output is a "Peritel" or "Scart" connector. Color was available on the RGB pins and the gray level information on the composite pin. The TMS 3556 is designed for European video systems, so the card will only work with a 50Hz screen refresh rate.

Presentation GTEXTEGTEXTE commands

µInflux HRC 80 board

The commands for the Basic extensions GTEXTE and GBASIC are described here.

After the µInflux company folded, the HRC 80 was supported by Pentasonic. The Pentasonic HifiColor card could be seen as an extended successor to the HRC 80.

Local links:

More documentation in the documentation directory.

Last update: 2013-02-15