Addressor Card (for use with 128K and larger Memory Expanders)

The card that lets an ADAM reach memory beyond 64K. It holds no memory itself - it sits in slot #2 and does the addressing while the RAM lives on a separate card.

Why two cards

• The ADAM's expansion bus was designed around a 64K expander. Anything larger needs the extra address lines this provides.
• Without it, a 512K card behaves as an ordinary 64K expander. The memory is present and unreachable, which is the commonest confusion with these cards.

What uses it

• Most ADAM software sees only the base 64K plus 64K, whatever is fitted.
• CP/M and T-DOS see all of it and use the remainder as a RAM disk.

Orphanware's own expanders from 128K to 512K are catalogued alongside this. Micro Innovations, MicroFox and E&T all made equivalent addressor cards, and Eric Pearson's MIB238 carries the function on a card that does several other jobs as well.