Hitachi ABB RVT Installation Und Betriebsanleitung Seite 556

QUERY
Slave address
Function
Error check field CRC
The 64 bytes wide Event log buffer is filled with communication events. The most recent communications event is
shown in the Event 0 byte.
Event bytes are stored in the Even log buffer for 4 different reasons.
The bit will be set to logic '1' if the corresponding condition is TRUE.
Slave Modbus Receive Event
This type of event byte is stored by the slave when a query message is received.
It is stored before the slave processes the message.
Bit Contents
0 Not Used
1 Communications Error
2 Not Used
3 Not Used
4 Character Overrun
5 Currently in Listen Only Mode
6 Broadcast Received
7 1
Slave Modbus Send Event
This type of event byte is stored by the slave when it finishes processing a query message.
It is stored if the slave returned a normal or exception response, or no response.
Bit Contents
0 Read Exception Sent (Exception Codes 1-3)
1 Slave Abort Exception Sent (Exception Code 4)
2 Not used
3 Not used
4 Write Timeout Error Occurred
5 Currently in Listen Only Mode
6 1
7 0
Slave Entered Listen Only Mode
STATUS
Approved
RESPONSE
1 byte Slave address
1 byte Function
2 bytes Byte count
Status word
Event counter
Bus message counter
Event log buffer
Error check field CRC
SECURITY LEVEL
Public
1 byte (echo of master's query)
1 byte (echo of master's query)
1 byte
2 bytes (0)
2 bytes
2 bytes
N bytes
2 bytes
DOCUMENT ID
9AKK106713A9758
RVT CO MM UNI CATI O N
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