Fujitsu F2MC-8L Family series Hardware Manual page 78

Peripherals
HARDWARE CONFIGURATION
(5) Operation
First, write the data to be displayed to display RAM. Then, set the value
corresponding to the LCD panel to be used to LCDR (LCD control register).
The LCD drive waveform is output according to the data in the display RAM,
when the clock pulse is supplied.
The display drive output has a 2-frame AC waveform. The combination of
bias and duty shown below may be possible. Note that the combination of
1/3 bias and 1/2 duty should not be used. Examples of waveforms are
shown on the following pages.
1/2 duty
1/2 bias
1/3 bias
In the 1/2 duty mode, the COM2 and COM3 output waveforms are non-
selective level. The COM3 output waveform is also a non-conforming
waveform at 1/3 duty.
When LCD operation is terminated, both common and segment produce
waveforms at L level. However, when SEG20 to SEG41 are specified as
general-purpose port by the mask option, segment data are not output.
2– 63
1/3 duty
×
×
: Recommended mode
×
: Application disabled
1/4 duty
×