Tandy PLUS Memory Expansion Board
The PLUS Memory Expansion Board was used with the Tandy 1000EX and 1000HX.
It was required in order to add DMA capability to either machine, as well
as to bring either machine to a full 640k of RAM. It also added two additional
'PLUS' style expansion connectors, as without it, there was only a single
connector in which to plug other 'PLUS' style expansion cards. Non-Tandy
boards were also available to fill the same role, though at least one of these
cards only provided a single additional expansion connector. The PLUS memory
board carried Tandy part# 25-2062 and listed for $$189.99.
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