Datasheet

78K0/Ix2 CHAPTER 16 SERIAL INTERFACE CSI11
R01UH0010EJ0500 Rev.5.00 555
Feb 28, 2012
16.4 Operation of Serial Interface CSI11
Serial interface CSI11 can be used in the following two modes.
 Operation stop mode
 3-wire serial I/O mode
16.4.1 Operation stop mode
Serial comm
unication is not executed in this mode. Therefore, the power consumption can be reduced. In addition,
the SCK11, SI11, SO11, and SSI11 pins can be used as ordinary I/O port pins in this mode.
(1) Register used
The operation stop mode is set by serial operation mode register 11 (CSIM11).
To set the operation stop mode, clear bit 7 (CSIE11) of CSIM1n to 0.
(a) Serial operation mode register 11 (CSIM11)
CSIM11 can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation clears CSIM11 to 00H.
Address: FF88H After reset: 00H R/W
Symbol <7> 6 5 4 3 2 1 0
CSIM11 CSIE11 TRMD11 SSE11 DIR11 0 0 0 CSOT11
CSIE11 Operation control in 3-wire serial I/O mode
0 Disables operation
Note 1
and asynchronously resets the internal circuit
Note 2
.
Notes 1. To use P37/SO11, P35/SCK11, and P02/SSI11/INTP5 as general-purpose ports set CSIM11 in the
default status (00H).
2. Bit 0 (CSOT11) of CSIM11 and serial I/O shift register 11 (SIO11) are reset.