PT6555 Datasheet, PDF (22/28 Pages) Princeton Technology Corp – LCD Driver IC

PT6555
Every t8 period, the controller checks the state of the DO Pin when CE is at “LOW” state. If the DO is at “LOW” level, then
the controller validates that a key has been pressed and a key data read operation is performed. Please refer to the
timing diagram below. It must be noted however, that if a key data read operation is performed when DO is held “HIGH”,
the read key data - KD1 to KD30 and the sleep acknowledge bit SA will not be valid.
V1.1
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August, 2009