Now for the new bit. For years I wanted to be able to map this controller into memory addresses &FC44-47 as a "second Winchester controller" instead of the default of &FC40-43.

This can be done by modifying the signal fed to the address lines on the 1MHz bus. The board provides signals for A0-A7 which when added up as 8 binary bits, make the address in page &FC where the board appears. By default, it is &40, which is 01000000. This number is made up by all the address lines outputting a logic zero, except address line A6, which is a logic 1.

What I needed to do was also make address line A2 output a logic 1, turning the address into 01000100, or &44.

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