Csi4 Control Registers - NEC Renesas V850/SC1 User Manual

11.3.2 CSI4 control registers

CSI4 is controlled by the following registers.
•
Variable-length serial control register 4 (CSIM4)
•
Variable-length serial setting register 4 (CSIB4)
•
Baud rate generator source clock select register 4 (BRGCN4)
•
Baud rate generator output clock select register 4 (BRGCK4)
(1) Variable-length serial control register 4 (CSIM4)
This register is used to enable or disable the serial clock, operation modes, and specific operations of serial
interface channel 4.
CSIM4 can be set by an 8-bit or 1-bit memory manipulation instruction.
RESET input sets CSIM4 to 00H.
After reset: 00H
<7>
CSIM4 CSIE4
CSIE4
0
1
MODE4
0
1
SCL4
0
1
Notes 1. The SI4, SO4, and SCK4 pins are used as port function pins when CSIE4 = 0 (SIO4 operation
disabled state).
2. When CSIE4 = 1 (SIO4 operation enable state), the port function is available only for the SI4 pin
when only using the transmit function and to SO4 pin when using the receive-only function.
334
CHAPTER 11 SERIAL INTERFACE FUNCTION
R/W Address: FFFFF2E2H
6 5
0 0
SIO4 operation enable/disable specification
Shift register operation
Operation disabled
Operation enabled
Operation mode
Transmit/receive mode
Receive-only mode
External clock input (SCK4)
BRG (Baud rate generator)
User's Manual U15109EJ3V0UD
4 3 2
0 0 MODE4
Serial counter
Clear
Count operation enabled
Transfer operation mode flag
Transfer start trigger
SIO4 write
SIO4 read
Clock selection
1 0
0 SCL4
Port
Note 1
Port function
Note 2
Serial function + port function
SO4 output
Normal output
Port function