pcf8532 NXP Semiconductors, pcf8532 Datasheet - Page 21

• Manufacturer Part Number: pcf8532
• Description: Universal Lcd Driver For Low Multiplex Rates
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCF8532_1
Product data sheet
7.16.6 Input filters
7.16.7 I
To enhance noise immunity in electrically adverse environments, RC low-pass filters are
provided on the SDA and SCL lines.
Two I
The least significant bit of the slave address that a PCF8532 responds to is defined by the
level tied at its input SA0. The PCF8532 is a write only device and does not respond to a
read access. Two types of PCF8532 can be distinguished on the same I
allows:
The I
condition (S) from the I
addresses available. All PCF8532’s with the corresponding SA0 level acknowledge in
parallel to the slave address, but all PCF8532’s with the alternative SA0 level ignore the
whole I
After acknowledgement, a control byte follows which defines if the next byte is RAM or
command information. The control byte also defines if the next following byte is a control
byte or further RAM/command data.
In this way it is possible to configure the device then fill the display RAM with little
overhead.
The command bytes and control bytes are also acknowledged by all addressed
PCF8532’s 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 and the data is directed to the intended PCF8532 device.
The acknowledgement after each byte is made only by the (A0 and A1) addressed
PCF8532. After the last (display) byte, the I
Alternatively a START may be issued to RESTART an I
2
•
•
C-bus protocol
Up to 8 PCF8532’s on the same I
The use of two types of LCD multiplex on the same I
2
2
C-bus protocol is shown in
C-bus slave addresses (0111 000 and 0111 001) are reserved for the PCF8532.
2
C-bus transfer.
Rev. 1 — 10 February 2009
2
C-bus master which is followed by one of the two PCF8532 slave
Figure
2
C-bus for very large LCD applications
15. The sequence is initiated with a START
Universal LCD driver for low multiplex rates
2
C-bus master issues a STOP condition (P).
2
C-bus access.
2
C-bus.
PCF8532
© NXP B.V. 2009. All rights reserved.
2
C-bus which
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