(± 15x10cm)

The second big project from the FAC.
On this pc-board is room for 8 EPROM's ( roms ) on the #Axxx block and 2 places for 4K C-mos, at choice #Axxx or #Exxx. (see diagram ) The #Exxx block has to be converted to #1xxx when one uses the Atom FDC system.
Based on the switching routine ("chair-program") from B.Poot, a number of excellent switching-systems were developed.
( Branquart -system and CX -system )

Atom-DOS users have to modify its #Exxx block to #1xxx with a piggyback. On #1000 a switching routine can be loaded with advantage, even on write-protect.

That is clearly an advantage over a plain C-mos ram card. For a an efficient use of the card it is unavoidable to modify the F-ROM and make an adjustment around IC23.

The old "schakelkaart"

The new "schakelkaart"