HD66724 Datasheet, PDF (47/117 Pages) Hitachi Semiconductor – (Graphics LCD Controller/Driver with Key Scan Function)

HD66724/HD66725
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0 0 0 1 1 0 1 IRE KF1 KF0
Figure 19 Key Scan Control Instruction
Table 26 KF Bits and Key Scan Cycle
KF1
KF0
Key Scan Pulse Width
Key Scan Cycle
0
0
0.25 ms
1.0 ms (32 clock cycles)
0
1
0.5 ms
2.0 ms (64 clock cycles)
1
0
1.0 ms
4.0 ms (128 clock cycles)
1
1
2.0 ms
8.0 ms (256 clock cycles)
Note: The data is a value obtained when the oscillation frequency (fosc) is 32 kHz. The value depends on
the oscillation frequency.
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