Sharp BE-2520 Service Manual page 44

BE-2520
7-9. IC Internal logic
74LS$138(3-8 Decoder ) 74LS$139 (Dual 2—4 Decoder ) MC14042 (TC4042) 4—Bit Latch
BLOCK DIAGRAM
DATA OUTPUTS SELECT DATA OUTPUTS
ENABLE
4 \ DO
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CLOCK
POLARITY
D1
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ENABLE| SELECT
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X H
es OUTPUTS
ENABLE | SELECT
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