LC75817E Datasheet, PDF (41/43 Pages) Sanyo Semicon Device – 1/8 to 1/10 Duty Dot Matrix LCD Display Controller/Driver with Key Input Function

LC75817E, 75817W
• Explanation
In this technique, the controller uses interrupts to determine key on/off states and read the key data. The controller
must check the DO state when CE is low. If DO is low, the controller recognizes that a key has been pressed and
executes the key data read operation. After that the next key on/off determination is performed after the time t10 has
elapsed by checking the DO state when CE is low and reading the key data. The period t10 in this technique must
satisfy the following condition.
t10 > t6
If a key data read operation is executed when DO is high, the read key data (KD1 to KD30) and sleep acknowledge
data (SA) will be invalid.
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