Datasheet

V850ES/JG3 CHAPTER 16 3-WIRE VARIABLE-LENGTH SERIAL I/O (CSIB)
R01UH0015EJ0300 Rev.3.00 Page 490 of 870
Sep 30, 2010
(3/3)
Communication start trigger invalid
Communication start trigger valid
CBnSCE
0
1
Specification of start transfer disable/enable
• In master mode
This bit enables or disables the communication start trigger.
(a) In single transmission or transmission/reception mode, or continuous
transmission or continuous transmission/reception mode
The setting of the CBnSCE bit has no influence on communication operation.
(b) In single reception mode
Clear the CBnSCE bit to 0 before reading the last receive data because
reception is started by reading the receive data (CBnRX register) to disable
the reception startup
Note 1
.
(c) In continuous reception mode
Clear the CBnSCE bit to 0 one communication clock before reception of the
last data is completed to disable the reception startup after the last data is
received
Note 2
.
• In slave mode
This bit enables or disables the communication start trigger.
Set the CBnSCE bit to 1.
[Usage of CBnSCE bit]
• In single reception mode
<1>When reception of the last data is completed by INTCBnR interrupt
servicing, clear the CBnSCE bit to 0 before reading the CBnRX register.
<2>After confirming the CBnSTR.CBnTSF bit = 0, clear the CBnRXE bit to 0 to
disable reception.
To continue reception, set the CBnSCE bit to 1 to start up the next reception
by dummy-reading the CBnRX register.
• In continuous reception mode
<1>Clear the CBnSCE bit to 0 during the reception of the last data by INTCBnR
interrupt servicing.
<2>Read the CBnRX register.
<3>Read the last reception data by reading the CBnRX register after
acknowledging the CBnTIR interrupt.
<4>After confirming the CBnSTR.CBnTSF bit = 0, clear the CBnRXE bit to 0 to
disable reception.
To continue reception, set the CBnSCE bit to 1 to wait for the next reception
by dummy-reading the CBnRX register.
Notes 1. If the CBnSCE bit is read while it is 1, the next communication operation is started.
2. The CBnSCE bit is not cleared to 0 one communication clock before the completion of
the last data reception, the next communication operation is automatically started.
Caution Be sure to clear bits 3 and 2 to “0”.