MC68HC908LJ12 Datasheet, PDF (319/413 Pages) Freescale Semiconductor, Inc – 8-bit microcontroller units

Liquid Crystal Display Driver (LCD)
$005A
$005B
$005C
$005D
$005E
$005F
Read:
LCD Data Register 9
(LDAT9)
Write:
Reset:
F17B3
U
F17B2
U
Read:
LCD Data Register 10
(LDAT10)
Write:
Reset:
F19B3
U
F19B2
U
Read:
LCD Data Register 11
(LDAT11)
Write:
Reset:
F21B3
U
F21B2
U
Read:
LCD Data Register 12
(LDAT12)
Write:
Reset:
F23B3
U
F23B2
U
Read:
LCD Data Register 13
(LDAT13)
Write:
Reset:
F25B3
U
F25B2
U
Read:
LCD Data Register 14
(LDAT14)
Write:
Reset: U
U
U = Unaffected
F17B1 F17B0 F16B3
U
U
U
F19B1 F19B0 F18B3
U
U
U
F21B1 F21B0 F20B3
U
U
U
F23B1 F23B0 F22B3
U
U
U
F25B1 F25B0 F24B3
U
U
U
F26B3
U
U
U
= Unimplemented
Figure 16-1. LCD I/O Register Summary
F16B2
U
F18B2
U
F20B2
U
F22B2
U
F24B2
U
F26B2
U
F16B1
U
F18B1
U
F20B1
U
F22B1
U
F24B1
U
F26B1
U
F16B0
U
F18B0
U
F20B0
U
F22B0
U
F24B0
U
F26B0
U
16.5 Functional Description
Figure 16-2 shows a block diagram of the LCD driver module, and
Figure 16-3 shows a simplified schematic of the LCD system.
The LCD driver module uses a 1/3 biasing method. The LCD power is
supplied by MCU power supply V_DD. Voltages V_LCD1, V_LCD2, and V_LCD3
are generated by an internal resistor ladder.
The LCD data registers, LDAT1–LDAT14, control the LCD segments’
ON/OFF, with each data register controlling two frontplanes. When a
logic 1 is written to a FxBx bit in the data register, the corresponding
frontplane-backplane segment will turn ON. When a logic 0 is written, the
the segment will turn OFF.
Technical Data
320
Liquid Crystal Display Driver (LCD)
MC68HC908LJ12 — Rev. 2.1
Freescale Semiconductor