
CHAPTER 18 IEBus CONTROLLER
User’s Manual U16541EJ4V0UD
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18.4.4 Communication error source processing list
The following table shows the occurrence conditions of the communication errors (timing error, NACK reception
error, overrun error, underrun error, parity error, and write error), error processing by the IEBus controller, and
examples of processing by software.
Table 18-18. Communication Error Source Processing List (1/2)
Timing Error
Unit status
Reception
Transmission
Occurrence
condition
If bit specification timing is not correct
Occurrence
condition
Location of
occurrence
Other than data field
Data field
Other than data field
Data field
Hardware
processing
Reception stops.
INTIE2 signal occurs
To start bit waiting status
Remark
Communication between other
units does not end.
Transmission stops.
INTIE2 signal occurs
To start bit waiting status
Broadcast
communication
Software
processing
Error processing (such as retransmission
request)
Error processing (such as retransmission
request)
Hardware
processing
Reception stops.
INTIE2 signal occurs
NACK signal is returned.
To start bit waiting status
Transmission stops.
INTIE2 signal occurs
To start bit waiting status
Individual
communication
Software
processing
Error processing (such as retransmission
request)
Error processing (such as retransmission
request)
NACK Reception Error
Unit status
Reception
Transmission
Occurrence
condition
Unit NACK signal transmission
Occurrence
condition
Location of
occurrence
Other than data
field
Data field
Other than data
field
Data field
NACK signal
reception of data
of 32nd byte
Hardware
processing
Broadcast
communication
Software
processing
Hardware
processing
Reception
stops.
INTIE2 signal
occurs.
To start bit
waiting status
INTIE2 signal
does not occur.
Data
retransmitted
by other unit is
received.
Reception
stops.
INTIE2 signal
occurs.
To start bit
waiting status
INTIE2 signal
does not occur.
Retrans-
mission
processing
INTIE2 signal
occurs.
To start bit
waiting status
Individual
communication
Software
processing
Error
processing
(such as
retransmission
request)
Error
processing
(such as
retransmission
request)
Error
processing
(such as
retransmission
request)