pcf85176 NXP Semiconductors, pcf85176 Datasheet - Page 18

• Manufacturer Part Number: pcf85176
• Description: Universal Lcd Driver For Low Multiplex Rates
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCF85176_1
Product data sheet
7.13 Output bank selector
7.14 Input bank selector
7.15 Blinker
The hardware subaddress must not be changed while the device is being accessed on the
I
The output bank selector (see
address for transfer to the display register. The actual row selected depends on the
selected LCD drive mode in operation and on the instant in the multiplex sequence.
The PCF85176 includes a RAM bank switching feature in the static and 1:2 multiplex drive
modes. In the static drive mode, the bank-select command may request the contents of
row 2 to be selected for display instead of the contents of row 0. In the 1:2 multiplex mode,
the contents of rows 2 and 3 may be selected instead of rows 0 and 1. This gives the
provision for preparing display information in an alternative bank and to be able to switch
to it once it is assembled.
The input bank selector loads display data into the display RAM in accordance with the
selected LCD drive configuration. Display data can be loaded in row 2 in static drive mode
or in rows 2 and 3 in 1:2 multiplex drive mode by using the bank-select command (see
Table
The display blinking capabilities of the PCF85176 are very versatile. The whole display
can blink at frequencies selected by the blink-select command (see
frequencies are fractions of the clock frequency. The ratio between the clock and blink
frequencies depends on the blink mode selected (see
An additional feature is for an arbitrary selection of LCD elements to blink. This applies to
the static and 1:2 multiplex drive modes and can be implemented without any
communication overheads. By means of the output bank selector, the displayed RAM
banks are exchanged with alternate RAM banks at the blink frequency. This mode can
also be specified by the blink-select command.
In the 1:3 and 1:4 multiplex modes, where no alternative RAM bank is available, groups of
LCD elements can blink by selectively changing the display RAM data at fixed time
intervals.
2
C-bus interface.
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In 1:4 multiplex mode, all RAM addresses of row 0 are selected, these are followed by
the contents of row 1, row 2, and then row 3
In 1:3 multiplex mode, rows 0, 1, and 2 are selected sequentially
In 1:2 multiplex mode, rows 0 and 1 are selected
In static mode, row 0 is selected
13). The input bank selector functions independently to the output bank selector.
All information provided in this document is subject to legal disclaimers.
Rev. 01 — 14 April 2010
Table
13) selects one of the four rows per display RAM
Universal LCD driver for low multiplex rates
Table
6).
PCF85176
Table
© NXP B.V. 2010. All rights reserved.
14). The blink
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