PCA85232 Datasheet, PDF (26/54 Pages) NXP Semiconductors – LCD driver for low multiplex rates

NXP Semiconductors
PCA85232
LCD driver for low multiplex rates
The acknowledgement after each byte is made only by the (A0 and A1) addressed
PCA85232. After the last (display) byte, the I²C-bus master issues a STOP condition (P).
Alternatively a START may be asserted to RESTART an I²C-bus access.
7.17 Command decoder
The command decoder identifies command bytes that arrive on the I²C-bus. The
commands available to the PCA85232 are defined in Table 9.
Table 9. Definition of PCA85232 commands
Command
Operation code
Bit
7
6
5
4
mode-set
1
1
0
0
load-data-pointer-MSB 0
0
0
0
load-data-pointer-LSB
0
1
0
0
device-select
1
1
1
0
bank-select
1
1
1
1
blink-select
1
1
1
1
frequency-prescaler
1
1
1
0
3
2
1
0
E B M[1:0]
P[7:4]
P[3:0]
0
0
A[1:0]
1
0
I
O
0
AB BF[1:0]
1
F[2:0]
Reference
Table 10
Table 11
Table 12
Table 13
Table 14
Table 15
Table 16
Table 10.
Bit
7 to 4
3
2
1 to 0
Mode-set command bit description
Symbol
Value
Description
-
1100
fixed value
E
display status
0^[1]
disabled (blank)^[2]
1
enabled
B
LCD bias configuration^[3]
0^[1]
1
M[1:0]
1_{⁄3 bias}
1_{⁄2 bias}
LCD drive mode selection
01
static; BP0
10
1:2 multiplex; BP0, BP1
11
1:3 multiplex; BP0, BP1, BP2
00^[1]
1:4 multiplex; BP0, BP1, BP2, BP3
[1] Power-on and reset value.
[2] The possibility to disable the display allows implementation of blinking under external control; the enable bit
determines also whether the internal clock signal is available at the CLK pin (see Section 7.5.1).
[3] Not applicable for static drive mode.
PCA85232
Product data sheet
Table 11.
Bit
7 to 4
3 to 0
Load-data-pointer-MSB command bit description
Symbol
Value
Description
-
0000
fixed value
P[7:4]
0000^[1] to
1001
P7 to P4 defines the first 4 (most significant) bits of
the data pointer that indicates one of the 160 display
RAM addresses
[1] Power-on and reset value.
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 8 December 2010
© NXP B.V. 2010. All rights reserved.
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