Users Manual

Table Of Contents
R01UH0823EJ0110 Rev.1.10 Page 1136 of 1852
Nov 30, 2020
RX23W Group 35. I
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C-bus Interface (RIICa)
NACKE Bit (NACK Reception Transfer Suspension Enable)
This bit is used to specify whether to continue or discontinue the data transfer when NACK is received in transmit mode.
Normally, set this bit to 1.
When NACK is received with the NACKE bit set to 1, the next transfer operation is suspended.
When the NACKE bit is 0, the next transfer operation is continued regardless of the value of the received
acknowledgment bit.
For details on the NACK reception transfer suspension function, refer to
section 35.8.2, NACK Reception Transfer
Suspension Function
.
SCLE Bit (SCL Synchronization Enable)
This bit is used to specify whether to the SCL output is to be synchronized with the SCL input. Normally, set this bit to 1.
When the SCLE bit is set to 0 (SCL synchronization is disabled), the RIIC does not synchronize the SCL output with the
SCL input. In this setting, the RIIC outputs the clock with the transfer rate set in registers ICBRH and ICBRL regardless
of the SCL0 line state. For this reason, if the load of the I
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C-bus line is much larger than the specification value or if the
SCL output overlaps in multiple masters, the short-cycle SCL that does not meet the specification may be output. When
the SCL synchronization is not used, it also affects the generation of a start condition, restart condition, and stop
condition, and the continuous output of additional SCL.
This bit must not be set to 0 except for checking the output of the set transfer rate.