PCF8813 Datasheet, PDF (22/72 Pages) NXP Semiconductors – (67 + 1) x 102 pixels matrix LCD driver

Philips Semiconductors
(67 + 1) × 102 pixels matrix LCD driver
9.2.2 READ MODE
Product specification
PCF8813
handbook, full pagewidth
SCE
SCLK
SDATA
D/C DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
SDOUT
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
D/C
MGU633
Fig.24 Serial interface (3-line), read mode.
In the read mode of the interface, that the microcontroller
reads data from the PCF8813. To do this the
microcontroller has first to send a command, then the read
status command, and then the PCF8813 will respond by
transmitting data on the SDOUT line. After that, SCE is
required to go HIGH before a new command is sent (see
Fig.24).
The PCF8813 samples the SDATA data at rising SCLK
edges, but shifts SDOUT data at falling SCLK edges. Thus
the microcontroller reads SDOUT data at rising SCLK
edges.
After the read status command has been sent, the SDATA
line must be set to 3-state not later than at the falling SCLK
edge of the last bit.
The 8th read bit is shorter than the others because it is
terminated by the rising SCLK edge (see Fig.24). The last
rising SCLK edge sets SDOUT to 3-state after a delay
time (see time t₄ in Fig.44).
2004 Mar 05
22