pcf8811 NXP Semiconductors, pcf8811 Datasheet - Page 17

• Manufacturer Part Number: pcf8811
• Description: 80 X 128 Pixels Matrix Lcd Driver
• Manufacturer: NXP Semiconductors

Philips Semiconductors
11.1.2
The read mode of the interface means that the
microcontroller reads data from the PCF8811. To do so the
microcontroller first has to send a command (the read
status command) and then the PCF8811 will respond by
transmitting data on the SDO line. After that SCE is
required to go HIGH (see Fig.16).
2004 May 17
handbook, full pagewidth
handbook, full pagewidth
80
SDATA
SDATA
SCLK
SCLK
SCE
SCE
R
128 pixels matrix LCD driver
EAD MODE
data
DB7 DB6 DB5 DB4
data
display data string
(
ONLY EXTENDED COMMAND SET
data
and length data (two bytes)
display length instruction
data
data
Fig.15 Transmission interrupted by SCE.
data
Fig.14 Transmission of several bytes.
DB2 DB1 DB0
)
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
17
display data string
data
The PCF8811 samples the SDIN data on rising SCLK
edges, but shifts SDO data on falling SCLK edges. Thus
the microcontroller is supposed to read SDO data on rising
SCLK edges.
After the read status command has been sent, the SDIN
line must be set to 3-state not later then the falling SCLK
edge of the last bit (see Fig.16).
The serial interface timing diagram is given in Chapter 19.
data
data
last
instruction
DB7 DB6 DB5 DB4 DB3
instruction
DB7
DB2
DB6 DB5 DB4
Product specification
PCF8811
DB1 DB0
MGW746
MGW747