UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 458

• Manufacturer Part Number: UPD784026
• Description: 16/8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

16.3.2 Clocked Serial Interface Mode Registers (CSIM1, CSIM2)
and CSIM2 format is shown in Figure 16-11.
418
The CSIM1 and CSIM2 are 8-bit registers that specify operations in the 3-wire serial I/O mode.
These registers can be read or written to by an 8-bit manipulation instruction or bit manipulation instruction. The CSIM1
These registers are cleared to 00H by RESET input.
Caution Select whether data is transferred from the MSB first or LSB first before writing data to SIO. If this
Figure 16-11 Format of Clocked Serial Interface Mode Register 1 (CSIM1) and Clocked Serial Interface
CSIM1
CSIM2
CTXE1
CTXE2 CRXE2
selection is made after data has been written to SIO, the transfer sequence of the data already stored
in SIO is not changed.
7
Mode Register 2 (CSIM2)
CRXE1
6
CHAPTER 16 ASYNCHRONOUS SERIAL INTERFACE/3-WIRE SERIAL I/O
5
0
0
4
0
0
3
0
0
DIR1
DIR2 CSCK2
2
CSCK1
1
0
0
0
CSCKn
CTXEn
DIRn
Address
0FF84H
0FF85H
0
1
0
1
0
0
1
1
CRXEn
External input
clock to SCKn pin
Baud rate
generator output
MSB-first
LSB-first
Serial Clock Selection Bit
Operating Mode Specification
(Transfer Bit Order)
Source Clock
0
1
0
1
On Reset
00H
00H
Transmission /reception disabled,
or asynchronous serial interface
mode
Reception enabled
Transmission enabled
Transmission/reception enabled
Transmit/Receive Operation
R/W
R/W
R/W
Input
CMOS output
In case of SCKn
(CTXEn, CRXEn = 1)
(n = 1, 2)