Cautions - Fujitsu MB96300 series Hardware Manual

CHAPTER 26 LCD CONTROLLER/DRIVER
26.6

Cautions

Cautions covering the usage of LCD controller/driver
• Switching the frame period generation clocks:
- Frame period generation clocks (LCR:CSS) can be switched even during LCD display.
- However, switching may cause some screen flicker. To avoid such flicker, be sure to set the blanking
select bit (LCR:BK) to "1" (blank display) before switching.
• Depending on your LCD, different external divider resistors are used. Use appropriate resistor values.
• When the display mode is set to 1/2 duty cycle, non-selected waveform is output through the COM2 and
COM3 pins. For 1/3 duty cycle, the COM3 pin is used to output non-selected waveform.
• Inappropriate selection or setting of frame period generation clock (CSS), LCD drive power supply
control (VSEL), duty cycle (MS[1:0]) and frame period (FP[1:0]) results in inappropriate LCD display
• By default, LCD display is disabled in MCU Timer modes. To enable LCD display in MCU Timer
modes, use LCR:LCEN and make sure the required clock is operating.
• LCD display is disabled in MCU STOP mode
• Take care that the LCD display is not enabled if the required clock is not operating. Otherwise the LCD
panel might be damaged by DC voltage. Refer to the following tables.
Table 26.6-1 LCD operation except in MCU Timer modes or MCU STOP mode
CSS
0
1
1
1
1
688
CKSEL Sub RC
clock clock
CLKSC CLKRC
running running
X X X
0 No X
0 Yes X
1 X No
1 X Yes
MB96300 Super Series Hardware Manual
Operation for MS[1:0] ≠ "00"
LCD controller is running with Peripheral Clock CLKP1.
Do not use this setting! DC voltage is applied to the LCD
panel.
LCD controller is running with Sub Clock CLKSC.
Do not use this setting! DC voltage is applied to the LCD
panel.
LCD controller is running with RC Clock CLKRC.