HD66420 Datasheet, PDF (35/52 Pages) Hitachi Semiconductor – (RAM-Provided 160 Channel 4-Level Grey Scale Driver for Dot Matrix Graphics LCD)

HD66420
Set HOLT bit to 1 (control register 1)
Internal operation stops
Set DTY or GRAY bit to 1 (control register 2)
Wait for oscillation to stabilize
Oscillator 2 starts working
Clear HOLT bit to 0 (control register 1)
Internal operation starts
Figure 21 Procedure for Changing Oscillator
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