Atari 800 Computer // Mosaic 64K + 32K // GENUINE !

Description

For your consideration, a near-mint Atari 800 Home Computer, equipped with a total of
96 KB
of RAM, thanks to its (unique) Mosaic 64KB ram expansion.
As originally found, the system appears in pristine condition, remarkably well preserved (and stored), without any signs of corrosion on its metal frame or components
and minimal signs of use
. Cartridge hatch operates quietly and smoothly, remaining open in up-position, although not spring-loaded (back-force clips could be re-installed at any time, although not supplied with unit). The entire system (and its 64KB RAM expansion) has been carefully tested specifically for this auction.
The
Mosaic 64KB
appears to have been
professionally
installed, in the past. Thanks to its clever and flexible design, this RAM expansion is on a class of its own. By setting its logic-control jumpers, the following RAM configurations were tested on this
Atari 800
:
1. ANY-slot operation (all other slots
empty
):
Inserted in Slot 1 (Slots 2 and 3 empty): total 48KB of RAM, 48KB visible.
Inserted in Slot 2 (Slots 1 and 3 empty): total 64Kb of RAM, 52KB visible (48KB + any of
four
banks of
4KB
)
Inserted in Slot 3 (Slots 1 and 2 empty): total 64Kb of RAM, 52KB visible (48KB + any of
four
banks of
4KB
)
2. TERMINAL-slot operation (Mosaic-64KB on Slot-3):
[16KB in Slot 1], [16KB in Slot 2]:
total 96KB of RAM, 52KB visible (48KB + any of
twelve
banks of 4KB)
[32KB in Slot 1], [16KB in Slot 2]:
total 112KB of RAM, 52KB visible (48KB + any of
sixteen
banks of 4KB)
[16KB in Slot 1], [32KB in Slot 2]:
total 112KB of RAM, 52KB visible (48KB + any of
sixteen
banks of 4KB)
There maybe other possible configuration modes, but those were not tested.
As shipped, the system is fitted, configured and tested to work with [16KB in Slot 1], [16KB in Slot 2], and [Mosaic-64KB on Slot 3], for a total of
96KB
of RAM, per above description and organization.
The following is a complete summary of all items included on this auction (as shown in pictures):
x1 Atari 800 Home Computer (pristine, tested)
x3 Atari 16KB RAM cards (like new, tested)
x1 Mosaic 64KB Select RAM expansion (like new, tested)
x1 Mosaic 32KB RAM expansion (boots in Slot 1 or 2, but NOT passing parity test, 00-block, bit-3)
x1 Original,
serial-matching
box, manuals and papers for Mosaic 32KB RAM expansion, in excellent condition.
x1 Original,
serial-matching
box for Mosaic 32KB,
in excellent condition.
x1 Atari 9v AC (50 watt) power-supply, in original box (tested, in very good condition)
x1 SIO cable (in very good condition)
x1 Composite Video + separate Audio cable (like new).
No additional shipping charges, for continental U.S deliveries, only.
Items will be professionally packed and shipped, for extra protection during transit.
You  can buy with confidence.
Enjoy!