CHAPTER 16 SERIAL INTERFACES CSI10 AND CSI11
Preliminary User’s Manual U17260EJ3V1UD
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16.4.2 3-wire serial I/O mode
The 3-wire serial I/O mode is used for connecting peripheral ICs and display controllers with a clocked serial
interface.
In this mode, communication is executed by using three lines: the serial clock (SCK1n), serial output (SO1n), and
serial input (SI1n) lines.
(1) Registers used
•
Serial operation mode register 1n (CSIM1n)
•
Serial clock selection register 1n (CSIC1n)
•
Port mode register 0 (PM0) or port mode register 1 (PM1)
•
Port register 0 (P0) or port register 1 (P1)
The basic procedure of setting an operation in the 3-wire serial I/O mode is as follows.
<1> Set the CSIC1n register (see
Figures 16-5
and
16-6
).
<2> Set bits 0 and 4 to 6 (CSOT1n, DIR1n, SSE11 (serial interface CSI11 only), and TRMD1n) of the CSIM1n
register (see
Figures 16-3
and
16-4
).
<3> Set bit 7 (CSIE1n) of the CSIM1n register to 1.
→
Transmission/reception is enabled.
<4> Write data to transmit buffer register 1n (SOTB1n).
→
Data transmission/reception is started.
Read data from serial I/O shift register 1n (SIO1n).
→
Data reception is started.
Caution Take relationship with the other party of communication when setting the port mode register
and port register.
Remark
n = 0:
µ
PD78F0531, 78F0532, 78F0533
n = 0, 1:
µ
PD78F0534, 78F0535, 78F0536, 78F0537, 78F0537D