UPD78F0838 Renesas Electronics Corporation., UPD78F0838 Datasheet - Page 695

• Manufacturer Part Number: UPD78F0838
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

<R>
17.4 Setting LCD Controller/Driver
Remark Use the following procedure to set to the display-off state and disconnect the internal resistors when
Caution When displaying in a mode with a large number of COMs, such as 4 COM, VLC0 may not be able
Set the LCD controller/driver using the following procedure:
<1>
<2>
<3>
<4>
<5>
<6>
<7>
Subsequent to this procedure, set the data to be displayed in the data memory.
Set the LCD drive method via MDSET0 and MDSET1 (bits 4 and 5 of the LCD mode register (LCDMD)).
Set the pins to be used as segment outputs to the port function registers (LCDPF0, LCDPF3, LCDALL).
Set an initial value to the RAM for LCD display.
Set the number of time slices via LCDM0 to LCDM2 (bits 0 to 2 of the LCD display mode register (LCDM)).
Set the LCD source clock and LCD clock via LCD clock control register (LCDC0).
Set SCOC (bit 6 of the LCD display mode register (LCDM)) to 1.
Start output corresponding to each data memory by setting LCDON (bit 7 of the LCD display mode register
(LCDM)) to 1.
using the internal resistance division method.
<1> Clear LCDON (bit 7 of LCDM) (LCDON = 0).
<2> Clear SCOC (bit 6 of the LCD display mode register (LCDM)) (SCOC = 0).
<3> Assume MDSET0, MDSET1 (bits 4 and 5 of the LCD mode register (LCDMD)) = (0, 0) and
to obtain sufficient contrast under the low-voltage conditions, depending on the panel
characteristics. Use the LCD controller/driver after having performed thorough LCD display
evaluation and confirmed that there are no problems regarding the display quality.
Deselect signals are output from all segment pins and common pins, and a non-display state is
entered.
Ground levels are output from all segment pins and common pins.
set to no internal resistor connection (power save mode).
CHAPTER 17 LCD CONTROLLER/DRIVER
Preliminary User’s Manual U19748EJ1V0UD
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