PCA8534A All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2015. All rights reserved.
Product data sheet Rev. 4 — 16 April 2015 28 of 53
NXP Semiconductors
PCA8534A
Automotive LCD driver for low multiplex rates
After acknowledgement, the control byte is sent defining if the next byte is a RAM or
command information. The control byte also defines if the next byte is a control byte or
further RAM or command data (see Figure 18
and Table 18). In this way, it is possible to
configure the device and then fill the display RAM with little overhead.
The command bytes and control bytes are also acknowledged by all addressed
PCA8534A connected to the bus.
The display bytes are stored in the display RAM at the address specified by the data
pointer and the subaddress counter. Both data pointer and subaddress counter are
automatically updated.
Fig 17. I
2
C-bus protocol
(;$03/(6
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PJO
6
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6
FRQWUROE\WH
VODYHDGGUHVV
5$0FRPPDQGE\WH
5$0'$7$
0
6
%
/
6
%
$
$
3
5:
6
$
6
$
$
$
35$0'$7$ $
EWUDQVPLWWZRFRPPDQGE\WHV
&200$1'
6
$
6
$
$
$
3&200$1' $$
FWUDQVPLWRQHFRPPDQGE\WHDQGWZR5$0GDWHE\WHV
&200$1'
6
$
6
$
$
$
35$0'$7$ $ 5$0'$7$ $$
&
2
5
6
Fig 18. Control byte format
Table 18. Control byte description
Bit Symbol Value Description
7CO continue bit
0 last control byte
1 control bytes continue
6RS register selection
0 command register
1 data register
5 to 0 - unused
PJO
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56
06% /6%
