NEC 78K0 Series User Manual page 389

Figure 16-4. Format of Serial Operation Mode Register 11 (CSIM11)
Address: FF88H After reset: 00H R/W
Symbol <7>
CSIM11 CSIE11
CSIE11
0 Disables operation
1 Enables operation
Note 4
TRMD11
Note 5
0 Receive mode (transmission disabled).
1 Transmit/receive mode
Notes 6, 7
SSE11
0 SSI11 pin is not used
1 SSI11 pin is used
Note 8
DIR11
0 MSB
1 LSB
CSOT11
0 Communication is stopped.
1 Communication is in progress.
Notes 1. Bit 0 is a read-only bit.
2. To use P02/SO11, P04/SCK11, and P05/SSI11/TI001 as general-purpose ports, set CSIM11 in the
default status (00H).
3. Bit 0 (CSOT11) of CSIM11 and serial I/O shift register 11 (SIO11) are reset.
4. Do not rewrite TRMD11 when CSOT11 = 1 (during serial communication).
5. The SO11 output (see (a) in Figure 16-2) is fixed to the low level when TRMD11 is 0. Reception is
started when data is read from SIO11.
6. Do not rewrite SSE11 when CSOT11 = 1 (during serial communication).
7. Before setting this bit to 1, fix the SSI11 pin input level to 0 or 1.
8. Do not rewrite DIR11 when CSOT11 = 1 (during serial communication).
CHAPTER 16 SERIAL INTERFACES CSI10 AND CSI11
Note 1
6 5
TRMD11 SSE11
Operation control in 3-wire serial I/O mode
Note 2
and asynchronously resets the internal circuit
Preliminary User's Manual U17260EJ3V1UD
4 3
DIR11 0
Transmit/receive mode control
SSI11 pin use selection
First bit specification
Communication status flag
2 1 0
0 0 CSOT11
Note 3
.
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