The BBC Master has a MOS ROM that includes 8 pages of ROM.
This are MOS, Terminal, View, ADFS, BASIC, ANFS and DFS.

There are a few updates for this ROM’s and there are compability issues.

You cannot easily change the ROM because it is 28 pin socket and EPROM or FLASH has at least 32 pin.

This is why I have designed a simple ROM converter/switch the can hold up to four different set’s of ROM’s.

This design is one of the smallest and can use either 27C010/27C020/040 or flash 29C020.
This chips are still easy to get hold on.

You can buy a DIY kit from me with all parts or you can by it ready build and tested.
I will also offer a FLASH with the ROM’s preinstalled.

Prices are for version 1.0

Product NOK Pund Euro Dollar
Kit 50.- 4.80 5.60 5.90
Build 100.- 9.50 11.20 11.80
FLASH 50.- 4.80 5.60 5.90
Shipping 26 3.0 3.50 4.50

If you want more then one please as for price.

The ROM/Flash includes.

MOS 3.2 with Y2K fixes
MOS 3.5 with Y2K fixes and DFS 2.45 fixes
ROM 9 DFS 2.24+Mouse – DFS 2.24 with double density bugfix, SRAM 1.04, Mouse 1.00

The ROMS images can be found here. Not sure if the CopyRight still applies, if so you need to own a legal copy.

If you need a special ROM combination please let me know.


Del dette:
  1. Hi

    ” DIY BBC Master quad OS ROM switch ” Page
    I have just purchased the DIY BBC Master quad OS ROM switch from you.

    I am unable to access the link to the ROMs ” ROMS images ” ? I don’t have permission ??

    Can you help Please

    Keep Safe

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