Interdata

Interdata was a company which produced a line of minicomputers. They started with 16-bit machines, and added a 32-bit line; the latter were initially upward compatible with the former. They were later the Computer Systems Division of Perkin-Elmer, Inc.

Interdata machines supported several different buses, which were generally standardized and available across the line:

• the 'Multiplexor bus', which supported programmed I/O
• the ' Selector Channel bus', which supported DMA

The 32-bit machines are somewhat famous for being the first ISA after the PDP-11 to which UNIX was moved (they were, for a short period before the arrival of the VAX, the only 32-bit minicomputer).

16-bit machines

• Interdata Model 70
• Interdata Model 74
• Interdata Model 80
• Interdata Model 85
• Interdata 3
• Interdata 4
• Interdata 5/16
• Interdata 6/16
• Interdata 7/16
• Interdata 8/16

32-bit machines

• Interdata 7/32
• Interdata 8/32

Interdata documentation does not directly address the question of whether the 8/32 is upwardly compatible with the 7/32; they use the same instruction formats, and thus addressing modes, though. (Operation codes are always 8 bits on both machines.)

External links

• interdata - documentation at Bitsavers
  • 32 Bit Series Reference Manual
  • I/O Interface Design Specification
  • Selector Channel