TRS-80 Expansion Interface 26-1140

The TRS-80 Expansion Interface (catalog number 26-1140) is the basic model, shipping with no additional RAM installed. Two other variants were also sold with catalog numbers 26-1141 and 26-1142, containing 16K and 32K or RAM respectively.

In addition to allowing extra RAM to be fitted to a TRS-80, the Expansion Interface also provides:

  • DIN jacks for two cassette records
  • Line printer card-edge for connection to Radio Shack Line Printers and other suitable parallel interface printers
  • Min-Disk card-edge for connection of up to four Radio-Shack Mini-Disk Drives
  • Expansion board card edge for use with the RS-232C Interface (or other custom designed PCB)
  • Bus card edge, which duplicates the signals present at the TRS-80 card edge.

In addition to these connections, the Expansion Interface provides a 25mS heartbeat interrupt to the computer (RTC).

The Expansion Interface is not compatible with a Level I TRS-80, only Level II.

Date : Unknown

Manufacturer : Tandy

Physical Description : TRS-80 interface sn-077756 outer box 5 foam incerts 1 ribbon 4 plastic clip on covers 5 pin - 5 pin male din cable Cassette interface cable expansion interface booklet level 2 basic ref manual back page to basic ref manual (loose from booklet) TRS-80 ref handbook service manual space warp games booklet SCRIPSIT training program book notes for NEWDOS booklet documents for NEWDOS booklet

This exhibit has a reference ID of CH40487. Please quote this reference ID in any communication with the Centre for Computing History.

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