Datasheet

78K0/Kx2-L CHAPTER 16 SERIAL INTERFACES CSI10 AND CSI11
R01UH0028EJ0400 Rev.4.00 576
Sep 27, 2010
16.4 Operation of Serial Interfaces CSI10 and CSI11
Serial interfaces CSI10 and 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 communication is not executed in this mode. Therefore, the power consumption can be reduced. In addition,
the SCK1n, SI1n, SO1n, 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 1n (CSIM1n).
To set the operation stop mode, clear bit 7 (CSIE1n) of CSIM1n to 0.
(a) Serial operation mode register 1n (CSIM1n)
CSIM1n can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation clears CSIM1n to 00H.
Remarks 1. 78K0/KA2-L (25, 32-pin products): n = 1
78K0/KB2-L: n = 0
78K0/KC2-L: n = 0, 1
2. The SSI11 pin is available only in 78K0/KA2-L (25, 32-pin products) and 78K0/KC2-L (48-pin
products).
• Serial operation mode register 10 (CSIM10)
Address: FF80H After reset: 00H R/W
Symbol <7> 6 5 4 3 2 1 0
CSIM10 CSIE10 TRMD10 0 DIR10 0 0 0 CSOT10
CSIE10 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 P10/SCK10 and P12/SO10 as general-purpose ports, set CSIM10 in the default status (00H).
2. Bit 0 (CSOT10) of CSIM10 and serial I/O shift register 10 (SIO10) are reset.