1-bit computing

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A 1-bit computer architecture is an instruction set architecture for a processor that has datapath widths and data register widths of 1 bit (1/8 octet) wide.

1-bit microprocessor MC14500BCP

An example of a 1-bit architecture that was actually marketed as a CPU is the Motorola MC14500B Industrial Control Unit.[1] There are also several design studies for 1-bit architectures in academia, and corresponding 1-bit logic can also be found in programming.

Other examples of 1-bit architectures are programmable logic controllers.

A typical sequence of instructions from a program for a 1-bit architecture might be:

  • load digital input 1 into a 1-bit register;
  • OR the value in the 1-bit register with input 2, leaving the result in the register;
  • write the value in the 1-bit register to output 1.

This architecture was considered superior when the program makes the decisions rather than performing computations, ladder logic, also for serial data processing.[2]

1-bit CPUs can be considered obsolete now, not many kinds have been produced (MC14500B and WDR-1 known) and none known to be available in the major computer component stores (as of 2016, a few on eBay[3]). Finnish company Partco still sells MC14500B as spare part in 2017.[4]

See also

References

  1. ^ "MC14500B Industrial Control Unit. Semiconductor Technical Data, Rev. 3" (PDF). Motorola. 1995. Retrieved December 21, 2016.
  2. ^ Motorola MC14500B Application Handbook
  3. ^ http://www.ebay.com/itm/Motorola-IC-MC14500B-MC14500BCL-100-NEW-/320837692605
  4. ^ "CMOS-LOGIC IC 4500 DIP16". Retrieved January 3, 2017. Also known as MC14500BCP