CHAPTER 13 SERIAL INTERFACE CSI10
Preliminary User’s Manual U16846EJ1V0UD
265
13.3 Registers Controlling Serial Interface CSI10
Serial interface CSI10 is controlled by the following four registers.
•
Serial operation mode register 10 (CSIM10)
•
Serial clock selection register 10 (CSIC10)
•
Port mode register 1 (PM1)
•
Port register 1 (P1)
(1) Serial operation mode register 10 (CSIM10)
CSIM10 is used to select the operation mode and enable or disable operation.
CSIM10 can be set by a 1-bit or 8-bit memory manipulation instruction.
RESET input clears this register to 00H.
Figure 13-2. Format of Serial Operation Mode Register 10 (CSIM10)
Address: FF80H After reset: 00H R/W
Note 1
Symbol
<7>
6 5 4 3 2 1 0
CSIM10 CSIE10 TRMD10
0
DIR10
0
0
0
CSOT10
CSIE10
Operation control in 3-wire serial I/O mode
0
Disables
operation
Note 2
and asynchronously resets the internal circuit
Note 3
.
1
Enables
operation
TRMD10
Note 4
Transmit/receive
mode
control
0
Note 5
Receive mode (transmission disabled).
1
Transmit/receive
mode
DIR10
Note 6
First
bit
specification
0
MSB
1
LSB
CSOT10
Communication
status
flag
0
Communication is stopped.
1
Communication is in progress.
Notes 1.
Bit 0 is a read-only bit.
2.
When using P10/SCK10(/TxD0
Note 7
), P11/SI10(/RxD0
Note 7
), or P12/SO10 as a general-purpose port, see
CHAPTER 4 PORT FUNTIONS
and
Caution 3
of
Figure 13-3
.
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 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).
7.
µ
PD78F0102H and 78F0103H only.
Caution Be sure to clear bit 5 to 0.