TOSEC: Tangerine Oric 1 and Atmos 2012-04-23

Oric was the name used by Tangerine Computer Systems for a series of home computers, including the original Oric-1, its successor the Oric Atmos and the later Oric Stratos/IQ164 and Oric Telestrat models.

With the success of the Sinclair ZX Spectrum, Tangerine's backers had suggested a home computer and Tangerine formed Oric Products International Ltd to develop and release the Oric-1 in 1983. Further computers in the Oric range were released through to 1987 with Eastern European clones being produced into the 1990s.

Based on a 1 MHz 6502A CPU, the Oric-1 came in 16 KB or 48 KB RAM variants for £129 and £169 respectively, matching the models available for the popular ZX Spectrum and undercutting the price of the 48K Spectrum by a few pounds. Both Oric-1 versions had a 16 KB ROM containing the operating system and a modified BASIC interpreter.

During 1983, around 160,000 Oric-1s were sold in the UK, plus another 50,000 in France (where it was the year's top-selling machine). Although not quite the 350,000 predicted, this was enough for Oric International to be bought out and given sufficient funding for a successor model, the Atmos.

The Oric-1 improved somewhat over the Spectrum with a different keyboard design replacing the Spectrum's unusual Chiclet keyboard. In addition the Oric had a true sound chip, the programmable GI 8912, and two graphical modes handled by a semi-custom ASIC (ULA) which also managed the interface between the processor and memory. The two modes were a LORES text only mode (though the character set could be redefined to produce graphics) with 28 rows of 40 characters and a HIRES mode with 200 rows of 240 pixels above three lines of text. Like the Spectrum, the Oric-1 suffered from attribute clash—albeit to a lesser degree in HIRES mode, when a single row of pixels could be coloured differently from the one below in contrast to the Spectrum, which applied foreground and background color in 8 x 8 pixel blocks. As it was meant for the home market, it had a built in television RF modulator as well as RGB output and was meant to work with a basic audio tape recorder to save and load data. Error-checking of recorded programs was bugged, frequently causing user-created programs to fail when loaded back in. A nice feature was an almost standard (except for the connector) Centronics printer interface.

The Edenspring money enabled Oric International to release the Oric Atmos, which added a true keyboard and an updated V1.1 ROM to the Oric-1. The faulty tape error checking routine was still there. Soon after the Atmos was released, the modem, printer and 3.5 -inch floppy disk drive originally promised for the Oric-1 were announced and released by the end of 1984. A short time after the release of the Atmos machine, a modification for the Oric-1 was issued and advertised in magazines and bulletin boards. This modification enabled the Oric-1 user to add a second rom (containing the Oric Atmos system) to a spare rom socket on the Oric-1 circuit board. Then, using a basic DPST (double pole single toggle) switch, the users could then switch between the new Oric Atmos rom and the original Oric-1 rom at their leisure.