BECKHOFF BC3100 - Manual (Page 39)

PROFIBUS bus terminal controller BC3100
BC3100 39
Other DP services
Global_Control Sync and Freeze mode, both of which are supported by the bus terminal
controllers, are controlled with the Global_Control service. Thus, the
Clear_Data command is also set, which has the reaction defined in bits 8
and 9 from Register 3 in Table 0 of the bus terminal controller (see
Parametrisation).
Set_Slave_Address For the time being, modification of the station address via the bus is not
supported.
Acyclic DPV1 services
The register of terminals and the input, output and flag process image can
be accessed acyclically with the DPV1 services. Additionally, the available
terminals can be read out and the cycle time can be measured.
The BC3100 supports the MSAC_C1 connection for the DP master class 1
as well as a MSAC_C2 connection for a second master with a maximum
PDU length of 52 bytes (48 bytes of data). The significance of
Slot_Number and Index for read and write services will be described in the
following.
Terminal register
(Slot_Number: 1 – 64) As registers are only available to complex terminals, these are the only
ones that must be considered when assigning the Slot_Number. The first
complex (analogue) terminal is addressed with Slot_Number = 1, the next
with Slot_Number = 2, etc. The Index designates the register number. The
number of registers, which are to be read or written, can be determined
from the length (in bytes, must be even as the terminal register is built up in
words).