[TUHS] 6-bit, 7-bit and 9-bit byte UNIXes

Michael Davidson michael_davidson at pacbell.net
Fri Oct 1 10:58:48 AEST 2004

> Was there any UNIX with 6-bit wide, 7-bit wide or 9-bit wide bytes or all
> UNIXes are 8-bit wide bytes?

BBN had a version of UNIX for the C/70 machine which had 10 bit bytes.

This is memorialized in the "IP/TCP Implementation Status" section of the
historic RFC 801 which describes the NCP to TCP transition plan, thus:

APPENDIX D.  IP/TCP Implementation Status

   Please note that the information in this section may become quickly
   dated.  Current information on the status of IP and TCP
   implementations can be obtained from the file


      Date:  18 Nov 1981
      From:  Rob Gurwitz <gurwitz at BBN-RSM>

      The C/70 processor is a BBN-designed system with a native
      instruction set oriented toward executing the C language.  It
      supports UNIX Version 7 and provides for user processes with a
      20-bit address space.  The TCP/IP implementation for the C/70 was
      ported from the BBN VAX TCP/IP, and shares all of its features.

      This version of TCP/IP is running experimentally at BBN, but is
      still under development.  Performance tuning is underway, to make
      it more compatible with the C/70's memory management system.

[ ... ]

More information about the TUHS mailing list