The 1-bit architecture is a microprocessor or computer architecture that has a datapath width or a highest operand width of 1 bit. These architectures typically have a matching register file with registers width of 1 bit. Very few 1-bit architecture CPUs were commercially marketed.

Applications

1-bit MPUs and MCUs found some success in industrial equipment where actual calculations was not needed but simple Boolean operations dominated the majority of the task. For general purpose applications and other calculations-related applications, 1-bit was largely seen as obsolete even in the early 1970s. Most bit-serial applications quickly switched over to 4/8-bit and then 16-bit microprocessors. Today all 1-bit microprocessors are largely obsolete, even academia.

1-bit microprocessors

• Motorola MC14500
• General Instrument SBA
• General Instrument SBA-1

1-bit systems

• Motorola WDR-1-Bit Computer