PIC18F87K90 Datasheet, PDF (274/566 Pages) Microchip Technology – 64/80-Pin, High-Performance Microcontrollers with LCD Driver and nanoWatt XLP Technology

PIC18F87K90 FAMILY
REGISTER 20-3: LCDREF: LCD REFERENCE VOLTAGE CONTROL REGISTER
R/W-0
LCDIRE
bit 7
R/W-0
LCDIRS
R/W-0
LCDCST2
R/W-0
LCDCST1
R/W-0
LCDCST0
R/W-0
VLCD3PE
R/W-0
VLCD2PE
R/W-0
VLCD1PE
bit 0
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
bit 6
bit 5-3
bit 2
bit 1
bit 0
LCDIRE: LCD Internal Reference Enable bit
1 = Internal LCD reference is enabled and connected to the internal contrast control circuit
0 = Internal LCD reference is disabled
LCDIRS: LCD Internal Reference Source bit
If LCDIRE = 1:
1 = Internal LCD contrast control is powered by VDDCORE (3.3V) voltage
0 = Internal LCD contrast control is powered by VDD
If LCDIRE = 0:
Internal LCD contrast control is unconnected. LCD band gap buffer is disabled.
LCDCST<2:0>: LCD Contrast Control bits
Selects the resistance of the LCD contrast control resistor ladder:
111 = Resistor ladder is at maximum resistance (minimum contrast)
110 = Resistor ladder is at 6/7th of maximum resistance
101 = Resistor ladder is at 5/7th of maximum resistance
100 = Resistor ladder is at 4/7th of maximum resistance
011 = Resistor ladder is at 3/7th of maximum resistance
010 = Resistor ladder is at 2/7th of maximum resistance
001 = Resistor ladder is at 1/7th of maximum resistance
000 = Minimum resistance (maximum contrast); resistor ladder is shorted
VLCD3PE: Bias 3 Pin Enable bit
1 = Bias 3 level is connected to the external pin, LCDBIAS3
0 = Bias 3 level is internal (internal resistor ladder)
VLCD2PE: Bias 2 Pin Enable bit
1 = Bias 2 level is connected to the external pin, LCDBIAS2
0 = Bias 2 level is internal (internal resistor ladder)
VLCD1PE: Bias 1 Pin Enable bit
1 = Bias 1 level is connected to the external pin, LCDBIAS1
0 = Bias 1 level is internal (internal resistor ladder)
DS39957B-page 274
Preliminary
 2010 Microchip Technology Inc.