[Return to top] BBC micro compatible - CPU. By Lee Davison.
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Eurobeeb CPU card Introduction
This is the heart of the CUBE system and could run as a stand alone SBC as it has the following...
  • 65C02 CPU
  • 2 x 8k RAM (battery backed)
  • 16k EPROM
  • 6551 ACIA
  • 6522 VIA
  • uEM M3002 RTC
  • First things first.
    The original battery on this card had burst and it was beginning to corrode the surrounding metal. To halt this the battery was the first thing to go.

    Next as I am going to be experimenting with this card I also decided to replace the 'budget' sockets with some turned pin type.

    This involved desoldering and removing all the old sockets and then cleaning the board. Once the board was clean the new turned pin sockets were soldered in place and the board was thoroughly cleaned once more.

    Address map
    The address map appears to be very similar to that of the BBC micro. Which is what you would expect. Details to follow.
    EPROM and PROMs
    I've done a dump of the 27128A 16k EPROM that contains the OS code. You can download it as either a binary dump or Motorola S record here.
  • Download the OS EPROM as a Motorola S record file.
  • Download the OS EPROM as a binary dump.
  • There are also two 82S147Ns that do the address decoding. both are here as a binary dump or Motorola S record.
  • Download IC9 as a Motorola S record file.
  • Download IC9 as a binary dump.

  • Download IC10 as a Motorola S record file.
  • Download IC10 as a binary dump.
  • Circuit diagram
    See it here .

    e-mail me [e-mail]
    Last page update: 15th August, 2002.