267
CHAPTER 14 SERIAL INTERFACE SIO3
User’s Manual U15798EJ2V0UD
14.3 Register to Control Serial Interface SIO3
The serial interface SIO3 is controlled by serial operation mode register 3 (CSIM3).
(1) Serial operation mode register 3 (CSIM3)
This register is used to enable or disable SIO3’s serial clock, operation modes, and specific operations.
CSIM3 is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input sets the value of this register to 00H.
Caution In 3-wire serial I/O mode, set the port mode register (PMXX) as follows. Set the output latch
of a port set to output mode (PMXX = 0) to 0.
During serial clock output
PM22 = 0; Sets P22 (SCK3) to output mode
(master transmission or master reception)
P22 = 0; Sets output latch of P22 to 0
During serial clock input
PM22 = 1; Sets P22 (SCK3) to input mode
(slave transmission or slave reception)
Transmit/receive mode
PM21 = 0; Sets P21 (SO3) to output mode
P21 = 0; Sets output latch of P21 to 0
PM20 = 1; Sets P20 (SI3) to input mode
Receive mode
PM20 = 1; Sets P20 (SI3) to input mode
Содержание mPD780344 Series
Страница 2: ...2 User s Manual U15798EJ2V0UD MEMO...