BAT32G1x9 user manual | Chapter 23 LCD bus interface
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Rev.1.02
(4). LCD bus pin settings
The LCDB is used as a bidirectional bus interface for communicating with an external LCD driver chip with
the following setup.
• Set the PMC
registers to configure the pins to digital mode.
• Set the PM registers to set the pins
D B W R
————————
and DBRD
——————
multiplexing to output mode.
• Set the pin registers to set the pin output latches D B W R
————————
and DBRD
——————
multiplexes to
"1"
• Set the PM register to set the
PIN for DBD0 to DBD7 multiplexing to input mode. (When the output is multiplexed
from DBD0 to DBD7, the hardware automatically switches to the output mode, and does not require the user to
set it himself.)
• Set the pin register to set the PIN output latch for
DBD0
to
DBD7 multiplexing to "0"
Figure 23-19 LCD
bus pin setup flow
< 68 mode
(using
PCF2119x) >
Start
Set port registers
P1 <- 0x01
End
Set port mode control registers
Set port mode registers
R/W <- P06/DBWR,E <- P05/DBRD
Note2
D0 to D7 <=> P80 to P87
RS <- P10,
1
is active
PMC1 <- 0x00
P10~P12 digital mode
PM0 <- 0x9F
PM8 <- 0x00
PM1 <- 0xFE
PM14 <-0xFE
P05 and PC06 output mode
P80 to P87 input mode
Note1
P10 output mode
P140/CLKBUZ0 output mode
Note: 1
The P80
to
P87
pins must be set to input mode to act as an LCD bidirectional communication bus.
2. W h e n
LBTL.bit7 (LBEL) = 0, the
output
latch registers of the P
05
and
P06
pins must be set to
"1".