ibaBM-DP
Manual
Issue 1.7
27
The individual devices in the ring can work with different cycle times. However, these
cycle times have to be an integer multiple of the smallest cycle. Example: Device #1
works at a cycle of 0.5 ms, device #2 with 1 ms, device #3 with 4 ms, etc. If the maximum
data rate has been exceeded, ibaPDA issues an error message indicating that the time-
base has to be increased or the data amount has to be lowered.
The calculation of the maximum data amount depends on the fastest device in the ring.
This means: If you increase the cycle time of slow devices in the ring topology, this does
not mean that a higher amount of data can be transferred. Only if you increase the cycle
time of the fastest device, also the data amount can be increased.
For more information about data allocation in a 32Mbit Flex ring, see chapter 10.8.
Note
Due to the large data amounts which are usually acquired with ibaBM-DP, it is appropriate
in most cases to operate only one device on a 32Mbit Flex link (see chapter 8.1)
8.2
Data acquisition compatibility mode 32Mbit
Fig. 7: Configuration compatibility mode 32Mbit – Sniffer function and/or active slaves
If the device is operated in compatibility mode 32Mbit, only a unidirectional connection
is needed for acquiring the data in the ibaPDA system. The configuration data is trans-
mitted over an Ethernet connection.
Regarding the configuration as sniffer or active slave, the same is true as shown in the
example with 32Mbit Flex, see chapter 8.1.
