Intel 8251

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Intel C8251 Ic-photo-Intel--C8251.JPG
Intel C8251

The 8251 is a Universal Synchronous/Asynchronous Receiver/Transmitter (USART) packaged in a 28-pin DIP made by Intel. It is typically used for serial communication and was rated for 19.2 kilobits per second signalling rate.

Contents

It is commonly confused with the much more common 8250 UART that was made popular as the serial port in the IBM Personal Computer.

It includes 5 sections:

  1. read/write control logic
  2. transmitter
  3. receiver
  4. data bus system
  5. modem control

Variants

Model NumberTemperature RangeDate of ReleasePrice (USD) [list 1]
ID8251IndustrialMarch/April 1979 [1] $25.10
8251ACommercialMay/June 1980 [2] $6.40
  1. In quantities of 100 and up

Known uses

The Intel 8251A was used in the Intel SDK-86 MCS-86 System Design Kit [3] and the DEC LA120 printing terminal. [4] The device is also used in the IC-10 RS-232 interface for Kenwood HAM radios like TS-440S, TS-711, TS-811 and many others.


  1. Intel Corporation, "Microcomputer Component: New industrial grade product line answers the demand for high-reliability components to operate in industrial applications.", Intel Preview, March/April 1979, Pg. 11
  2. Intel Corporation, "Intel peripherals enhance 8086 system design", Intel Preview Special Issue: 16-Bit Solution, May/June 1980, Pg. 22
  3. "Intel SDK-86 MCS-86 System Design Kit User's Guide" (PDF). Archived from the original (PDF) on 2012-09-10. Retrieved 2016-08-19.
  4. LA120 Technical Manual

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