upd78f0148m1gka1-9eu Renesas Electronics Corporation., upd78f0148m1gka1-9eu Datasheet - Page 381

• Manufacturer Part Number: upd78f0148m1gka1-9eu
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

17.4 Operation of Serial Interface CSIA0
17.4.1 Operation stop mode
the P142/SCKA0, P143/SIA0, and P144/SOA0 pins can be used as ordinary I/O port pins in this mode.
Serial interface CSIA0 has the following three modes.
• Operation stop mode
• 3-wire serial I/O mode
• 3-wire serial I/O mode with automatic transmit/receive function
Serial communication is not executed in this mode. Therefore, the power consumption can be reduced. In addition,
(1) Register used
The operation stop mode is set by serial operation mode specification register 0 (CSIMA0). To set the
operation stop mode, clear bit 7 (CSIAE0) of CSIMA0 to 0.
(a) Serial operation mode specification register 0 (CSIMA0)
This is an 8-bit register used to control the serial communication operation.
This register can be set by a 1-bit or 8-bit memory manipulation instruction.
RESET input clears this register to 00H.
Address: FF90H
CSIMA0
CSIAE0
CSIAE0
< >
0
After reset: 00H
CSIA0 operation disabled (SOA0: Low level, SCKA0: High level) and
asynchronously resets the internal circuit
ATE0
CHAPTER 17 SERIAL INTERFACE CSIA0
User’s Manual U15947EJ3V1UD
ATM0
R/W
Control of CSIA0 operation enable/disable
MASTER0 TXEA0
< >
RXEA0
< >
DIR0
0
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