PCF8562TT-2 NXP [NXP Semiconductors], PCF8562TT-2 Datasheet - Page 21

• Manufacturer Part Number: PCF8562TT-2
• Description: Universal LCD driver for low multiplex rates
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
PCF8562
Product data sheet
7.10.5 Input bank selector
7.11 Blinking
The PCF8562 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 content of
row 2 to be selected for display instead of the content of row 0. In the 1:2 multiplex mode,
the content 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.
The bank-select command (see
static drive mode or in rows 2 and 3 in 1:2 mode. The input bank selector functions are
independent of the output bank selector.
The display blinking capabilities of the PCF8562 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.
Table 8.
[1]
The entire display can blink at a frequency other than the nominal blink frequency. This
can be effectively performed by resetting and setting the display enable bit E at the
required rate using the mode-set command (see
Blink mode
off
1
2
3
•
•
In 1:2 multiplex mode, rows 0 and 1 are selected
In static mode, row 0 is selected
Blink modes 1, 2, and 3 and the nominal blink frequencies 0.5 Hz, 1 Hz, and 2 Hz correspond to an
oscillator frequency (f
Blinking frequencies
All information provided in this document is subject to legal disclaimers.
clk
) of 1536 Hz (see
Rev. 6 — 16 June 2011
Normal operating mode ratio
-
--------- -
768
------------ -
1536
------------ -
3072
f
f
f
clk
clk
clk
[1]
Table
Section
14) can be used to load display data in row 2 in
Universal LCD driver for low multiplex rates
12).
Table
Table
11).
Nominal blink frequency
blinking off
2 Hz
1 Hz
0.5 Hz
8).
Table
15). The blink
PCF8562
© NXP B.V. 2011. All rights reserved.
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