Registers Controlling Serial Interfaces Csi10 And Csi11 - NEC 78K0 Series User Manual

16.3 Registers Controlling Serial Interfaces CSI10 and CSI11

Serial interfaces CSI10 and CSI11 are controlled by the following four registers.
• Serial operation mode register 1n (CSIM1n)
• Serial clock selection register 1n (CSIC1n)
• Port mode register 0 (PM0) or port mode register 1 (PM1)
• Port register 0 (P0) or port register 1 (P1)
(1) Serial operation mode register 1n (CSIM1n)
CSIM1n is used to select the operation mode and enable or disable operation.
CSIM1n can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation sets this register to 00H.
µ
Remark n = 0: PD78F0531, 78F0532, 78F0533
µ
n = 0, 1: PD78F0534, 78F0535, 78F0536, 78F0537, 78F0537D
Figure 16-3. Format of Serial Operation Mode Register 10 (CSIM10)
Address: FF80H After reset: 00H R/W
Symbol <7>
CSIM10 CSIE10
CSIE10
0
1
Note 4
TRMD10
Note 5
0
1
Note 6
DIR10
0
1
CSOT10
0
1
Notes 1. Bit 0 is a read-only bit.
2. To use P10/SCK10/T
(00H).
3. Bit 0 (CSOT10) of CSIM10 and serial I/O shift register 10 (SIO10) are reset.
4. Do not rewrite TRMD10 when CSOT10 = 1 (during serial communication).
5. The SO10 output (see (a) in Figure 16-1) is fixed to the low level when TRMD10 is 0. Reception is
started when data is read from SIO10.
6. Do not rewrite DIR10 when CSOT10 = 1 (during serial communication).
Caution Be sure to clear bit 5 to 0.
388
CHAPTER 16 SERIAL INTERFACES CSI10 AND CSI11
Note 1
6 5
TRMD10 0
Operation control in 3-wire serial I/O mode
Note 2
Disables operation and asynchronously resets the internal circuit
Enables operation
Receive mode (transmission disabled).
Transmit/receive mode
MSB
LSB
Communication is stopped.
Communication is in progress.
D0 and P12/SO10 as general-purpose ports, set CSIM10 in the default status
X
Preliminary User's Manual U17260EJ3V1UD
4 3
DIR10 0
Transmit/receive mode control
First bit specification
Communication status flag
2 1 0
0 0 CSOT10
Note 3
.