It goes in the Atari's cartridge port, a
little-used connector on the
side of the machine. Used an unusual type of edge connector, and
hardly any software was supplied on cartridges. Some sound samplers
used it, though. I think the signals available were read-only,
fine for ROMs, but preventing the use of the slot for most types
of peripherals.
I've not seen many ROM cartridges for it but there was a nice
VT-100 emulation cartridge available for it.
Jeff
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