M30222 Datasheet, PDF (154/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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Specifications in this manual are tentative and subject to change
MITSUBISHI MICROCOMPUTERS
M30222 Group
Rev. G
LCD Drive Control Circuit
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
LCD Static Drive
When bit 7 of the LCD expansion register is set, then the static drive function is enabled.
The following LCD pins get assigned the static drive function in one of the following groups: SEG35 to
SEG24, SEG35 to SEG27, or SEG35 to SEG32. Bits 6 and 5 of the LCD expansion register determine
the grouping of the static drive pins. All remaining LCD pins retain their normal LCD functions.
The waveforms that are output from the static drive pins are shown in Figure 1.123. When writing to
LCD RAM for static operation, write the data to all four bits assigned to that pin. (Refer to Table 1.50,
LCD display RAM map). For example, to set static SEG34 ON and SEG35 OFF, write F016 to address
011116.
LCDCK
STATIC COM
["0" written to LCD RAM]
STATIC SEG (pixel off)
["0" written to LCD RAM]
STATIC SEG (pixel on)
["1" written to LCD RAM]
Fig. 1.123. LCD drive waveform (static drive)
Voltage level
VL3
Vss
VL3
Vss
VL3
Vss
LCD Expansion Clock
When bit 7 of the LCD expansion register is set, the LCD expansion clock becomes active. In this mode
a clock (LCDCKout) synchronized to the internal LCD clock can be output from the mcu. The frequency
of LCDCLKout is set by the LCD clock divided counter and is:
f(LCDCKout) = (frequency of count source for LCDCK)
2 x (LCD clock divided counter + 1)
In addition, a synchronization signal (SYNCout) is output. When the LCD SYNCout initiation bit is set,
this signal will go active low at the beginning of the next LCD frame.
Refer to Figures 1.124 and 1.125.
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