pcf8534a NXP Semiconductors, pcf8534a Datasheet - Page 15

• Manufacturer Part Number: pcf8534a
• Description: Universal Lcd Driver For Low Multiplex Rates
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCF8534A_3
Product data sheet
7.11 Data pointer
The following applies to
The addressing mechanism for the display RAM is realized using the data pointer. This
allows the loading of an individual display data byte or a series of display data bytes, into
any location of the display RAM. The sequence commences with the initialization of the
data pointer by the load data pointer command. After this, the data byte is stored starting
at the display RAM address indicated by the data pointer (see
is stored, the data pointer is automatically incremented based on the selected LCD
configuration.
The contents of the data pointer are incremented as follows:
If an I
Consequently, the data pointer must be rewritten prior to further RAM accesses.
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Static drive mode: the eight transmitted data bits are placed in row 0 to eight
successive display RAM addresses.
1:2 multiplex drive mode: the eight transmitted data bits are placed in row 0 and 1 to
four successive display RAM addresses.
1:3 multiplex drive mode: the eight transmitted data bits are placed in row 0, 1 and 2
to three successive addresses. However, bit 2 of the third address is left unchanged.
This last bit can, if necessary, be controlled by an additional transfer to this address
but avoid overriding adjacent data because full bytes are always transmitted.
1:4 multiplex drive mode: the eight transmitted data bits are placed in
row 0, 1, 2 and 3 to two successive display RAM addresses.
In static drive mode by eight.
In 1:2 multiplex drive mode by four.
In 1:3 multiplex drive mode by three.
In 1:4 multiplex drive mode by two.
2
C-bus data access terminates early, the state of the data pointer is unknown.
Rev. 03 — 10 November 2008
Figure
11:
Universal LCD driver for low multiplex rates
Figure
PCF8534A
11). Once each byte
© NXP B.V. 2008. All rights reserved.
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