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User’s Manual U11302EJ4V0UM
CHAPTER 14 SERIAL INTERFACE CHANNEL 1
14.1 Functions of Serial Interface Channel 1
Serial interface channel 1 has the following three modes.
Table 14-1. Modes of Serial Interface Channel 1
Operation Mode
Pins Used
Features
Usage
Operation stop
mode
3-wire serial I/O
mode
(MSB-/LSB-first
switchable)
3-wire serial I/O
mode with
automatic transmit/
receive function
(MSB-/LSB-first
switchable)
–
SCK1 (serial clock),
SO1 (serial output),
SI1 (serial input)
SCK1 (serial clock),
SO1 (serial output),
SI1 (serial input)
• Used when serial transfer is not carried out.
• Power consumption can be reduced.
• Input and output lines are independent and
they can transfer/receive at the same time, so
the data transfer processing time is short.
• The start bit of 8-bit data to undergo serial
transfer is switchable between MSB and LSB.
• Mode with same function as 3-wire serial I/O
mode above plus automatic transmit/receive
function.
• Can transmit/receive data with a maximum of
64 bytes. Therefore, this function enables the
hardware to transmit/receive data to/from the
OSD (On Screen Display) device and device
with on-chip display controller/driver
independently of the CPU thus the software
load can be reduced.
–
These modes are used
for connection of
peripheral ICs and
display controllers that
incorporate a clocked
serial interface.