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Acorn Universal Second Processor Unit

The Universal Second Processor Unit is a second processor unit that allows any BBC Master internal co-processor boards to be installed, thereby allowing the BBC B and B+ to use them as external co-processors. It contained a power supply, interface logic and a connector that matched the internal co-processor connector built into the BBC Master main board. The possible co-processor boards were:

  • The Turbo board: a 4MHz 65C102 with 64KB RAM.
  • The Master 512 board: a 10MHz 80186 with 512KB RAM.
The universal second processor unit could also be attached to the BBC Master in addition to an internal co-processor. In this case only one of the second processors would be enabled, switchable through software.

Our unit has been fitted with the Master 512 co-processor board. It has a serial number of 03-ANC21-1000861.

Date : 1987

Manufacturer : Acorn Computers

Physical Description : Co-Processor Unit

This exhibit has a reference ID of CH34150. Please quote this reference ID in any communication with the Centre for Computing History.

Scan of Document: Acorn Universal Second Processor Unit

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