Serial Operating Mode Register 0 Format - NEC PD78056F User Manual

CHAPTER 16 SERIAL INTERFACE CHANNEL 0 ( PD78058F SUBSERIES)
(2) Serial operating mode register 0 (CSIM0)
This register sets serial interface channel 0 serial clock, operating mode, operation enable/stop wake-up
function and displays the address comparator match signal.
CSIM0 is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets CSIM0 to 00H.
Caution Do not switch the operating mode (3-wire serial I/O/ 2-wire serial I/O/SBI) while operation of
serial interface channel 0 is enabled. If switching the operation mode, first terminate the
serial operation, then carry out switching.
Figure 16-4. Serial Operating Mode Register 0 Format (1/2)
Symbol
7 6 5
CSIM0 CSIE0 COI WUP
R/W
CSIM01 CSIM00
0 Input Clock to SCK0 pin from off-chip
1 0 8-bit timer register 2 (TM2) output
1 1 Clock specified with bits 0 to 3 of timer clock select register 3 (TCL3)
R/W
CSIM CSIM CSIM
PM25 P25 PM26 P26 PM27 P27
04 03 02
Note 2 Note 2
0
0 1
1
Note 3 Note 3
0
1 0
1 0
Note 3 Note 3
0
1 1
1 0
Notes 1. Bit 6 (COI) is a read-only bit.
2. Can be used as P25 (CMOS input/output) when used only for transmission.
3. Can be used freely as port function.
Remark
PMXX : Port Mode Register
PXX
294
4 3 2 1
CSIM04 CSIM03 CSIM02 CSIM01 CSIM00
Serial Interface Channel 0 Clock Selection
Operation
Mode
3-wired serial
0 0 0 1
l/O mode
SBI mode
0 0 0 1
Note 3 Note 3
0 0 1
2-wired serial
l/O mode
0 0 0 1
Note 3 Note 3
0 0 1
: don't care
: Port Output Latch
0 Address After Reset
FF60H 00H
SIO/SB0/P25
Start Bit
Pin Function
MSB
SI0 Note 2
(Input)
LSB
MSB P25 (CMOS
input/output)
SB0 (N-ch
open-drain
input/output)
MSB P25 (CMOS
input/output)
SB0 (N-ch
open-drain
input/output)
R/W
R/W Note 1
SO0/SB1/P26 SCK0/P27
Pin Function Pin Function
SO0 SCK0 (CMOS
(CMOS output) input/output)
SB1 (N-ch SCK0 (CMOS
open-drain input/output)
input/output)
P26 (CMOS
input/output)
SB1 (N-ch SCK0 (N-ch
open-drain
open-drain
input/output)
input/output)
P26 (CMOS
input/output)
(Continued)