TMS9900

The TMS9900 was one of the first commercially available single-chip 16-bit microprocessors. Introduced in June 1976, it implemented Texas Instruments's TI-990 minicomputer architecture in a single-chip format, and was initially used for low-end models of that lineup. Its 64-pin DIP package made it more expensive to implement in smaller machines than the more common 40-pin package. It saw relatively few design wins outside TI's own use. Among those uses was their TI-99/4 and TI-99/4A home computers, which ultimately sold about 2.8 million units. By the mid-1980s, the microcomputer field was moving to 16-bit systems such as the Intel 8086 and newer 16/32-bit designs such as the Motorola 68000. With no obvious future for the chip, TI's Semiconductor division turned its attention to special-purpose 32-bit processors: the Texas Instruments TMS320, introduced in 1983, and the Texas Instruments TMS340 graphics processor. The 9900 architecture lived on into the 1990s as the Communications Processor in TI's TMS380 chipset for Token Ring networking (later Ethernet).