Technical data

R911305038 / 01 | Rexroth VCP-Operating Concept Electric Drives and Controls | Bosch Rexroth AG 5-123
Standard Mode
5.14.4 Liveness Flag
In some communication protocols, you cannot control the operability of
the interface in the controller. The Liveness flag has been developed
to address this shortfall. This is a simple function, which has proven
very effective in practice.
Whenever the controller needs to know whether the connection is still
active, it writes a logical 1, and subsequently a logical 0, to bit 3 of the
Write Coordination byte.
The operating device constantly monitors the Liveness flag in the Write
Coordination byte and compares it with the status of the Liveness flag
in the Read Coordination byte. As soon as the two bytes are no longer
the same, the operating device copies bit 3 from the Write Coordination
byte to the Read Coordination byte.
Within a timeout time, the controller must now also check whether both
statuses are identical.
5.14.5 Data Set Download Release
The controller determines the start time of a data set transfer from the
operating device to the controller by writing a logical 1 in the Data Set
Download Release bit.
When you determine the timeout time, remember to take the transfer
times and polling times into account.