Hardware Manual for the PCD2.M5 Series│Document 26/856; Version EN 12│2014-07-24
Saia-Burgess Controls AG
Communication interfaces
5
5-16
Serial interfaces on I/O module slots 0 - 3
5.5
Serial interfaces on I/O module slots 0 - 3
5.5.1 General remarks on the PCD2.F2xxx
System properties of PCD2.F2xxx modules:
The following points must be observed when using the PCD2.F2xxx interface
modules:
●
For each PCD system, up to 4 PCD2.F2xxx modules (8 interfaces) can be used
on slots 0…3.
●
The PCD2.M5_ system has a powerful processor which handles the application
as well as the serial interfaces. Processing of the interface modules requires
the appropriate CPU capacity. To determine the maximum communication
capacity per PCD2.M5_ system, note the following:
●
The communication volume is determined by the peripheral devices connected.
This will be the case, for example, where a PCD2 is used as an S-Bus slave
station. If a PCD2 controller is bombarded with heavy telegram traffic at high
baud rates, less CPU capacity will be left to handle the actual application. The
following rules apply here: the use of 8 interfaces at 9.6 kbps takes approx.
50% of CPU capacity. Two interfaces at 57.6 kbps also take up approx. 50% of
CPU capacity. Two interfaces at 115 kbps require approx. 60% of CPU
capacity.
●
If the PCD2 is the initiator of the communication, the communication volume,
and hence the communication capacity, will be determined by the user program
in the PCD2 (PCD2 used as master station). Theoretically, all interfaces can be
run at the maximum baud rate of 115 kbps. However, the effective data
throughput will be governed by the user program and the number of interfaces,
and may be quite low. The crucial factor is that the peripheral devices
connected can be run with the selected configuration and communication
capacity.
5.5.2 Communication ports on the PCD2.M5_
The PCD2.F2xxx modules are designed for insertion into slots 0...3 on a PCD2.M5_.
As shown in the figure below, the slots are designated as follows:
Slot 0:
Port 100 for the x.0 port on the PCD2.F2xxx module
Port 101 for the x.1 port on the PCD2.F2xxx module
Slot 1:
Port 110 for the x.0 port on the PCD2.F2xxx module
Port 111 for the x.1 port on the PCD2.F2xxx module
Slot 2:
Port 120 for the x.0 port on the PCD2.F2xxx module
Port 121 for the x.1 port on the PCD2.F2xxx module
Slot 3:
Port 130 for the x.0 port on the PCD2.F2xxx module
Port 131 for the x.1 port on the PCD2.F2xxx module
