The TekBios is a GEMDOS extension that creates simple access to a TEK 4/8 board or compatible board. The TekBios uses the opcodes 100 to 114.
The TEK 4/8 is a Transputer board for the ISA-bus. The board can be fitted with a processor of type T414 or T800 from Inmos. It was introduced in the magazine c't 10/1987 - 12/1987. For use on the Atari one also needs the universal bus interface from c't 7/1987.