Circuit Df'.scru'tion - Radio Shack TRS-80 Service Manual

All and more about Sharp PC-1500 at http://www.PC-1500.info
1. Chip Select Circu it
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4. CIRCUIT DESCRIPTION
·rC4011139fo. TC40Hl38f
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Th Di!'i)lay chip L . 3
~---------• To RA.\11, 2 <TC5514 P)
~-------------0--• To
1/0 PORT(l.Jl58J
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~-•To
ROM (SC6J3 J28E')
L - - - - - - - - - - - - - - - - - - - -+ To Module Unit
' - - - - - - - - - - - - - - - - - - - + To tttodule Unit
TC• OH1ss
I nt ern.al logic:
Truth Table
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- 12-
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