PCF2119AU NXP [NXP Semiconductors], PCF2119AU Datasheet - Page 31

• Manufacturer Part Number: PCF2119AU
• Description: LCD controllers/drivers Single-chip LCD controller and driver
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
PCF2119X
Product data sheet
10.2.1.3 Read_data
10.2.1.4 Write_data
Busy flag: The busy flag indicates the internal status of the PCF2119x. A logic 1 indicates
that the chip is busy and further instructions will not be accepted. The busy flag is output
to pin DB7 when bit RS = 0 and bit R/W = 1. Instructions should only be started after
checking that the busy flag is at logic 0 or after waiting for the required number of cycles.
Address counter: The address counter is used by both CGRAM and DDRAM, and its
value is determined by the previous Set_CGRAM and Set_DDRAM instruction. After a
read/write operation the address counter is automatically incremented or decremented
by 1. The address counter value is output to the bus (DB6 to DB0) when bit RS = 0 and bit
R/W = 1.
Table 14.
Read_data from CGRAM or DDRAM: Read_data reads binary 8-bit data from the
CGRAM or DDRAM. The most recent ‘set address’ command (Set_CGRAM or
Set_DDRAM) determines whether the CGRAM or DDRAM is to be read.
The Read_data instruction gates the content of the data register to the bus while pin E is
HIGH. After pin E goes LOW again, internal operation increments (or decrements) the
address counter and stores RAM data corresponding to the new address counter into the
data register.
There are only three instructions that update the data register:
Other instructions (e.g. Write_data, Curs_disp_shift, Clear_display and Return_home) do
not modify the value of the data register.
Table 15.
Write_data to CGRAM or DDRAM: Write_data writes binary 8-bit data to the CGRAM or
the DDRAM.
Bit
RS
R/W
7 to 0
Bit
RS
R/W
7 to 0
•
•
•
Set_CGRAM
Set_DDRAM
Read_data from CGRAM or DDRAM
Symbol
-
-
READ_DATA
Symbol
-
-
WRITE_DATA 00000000 to
Read_data bit description
Write_data bit description
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 15 November 2010
Value
1
1
00000000 to
11111111
Value
1
0
11111111
Description
see
read data from CGRAM or DDRAM
Description
see
write data to CGRAM or DDRAM
Table 10
Table 10
LCD controllers/drivers
PCF2119x
© NXP B.V. 2010. All rights reserved.
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