Siemens MOBY FC 56 Technical Description page 124

Programming MOBY-ASM on PROFIBUS-DP-V1
Communication between ASM and PROFIBUS master
PROFIBUS-DP must be able to transfer both the cyclic (DP) and the non-cyclic
data (DP-V1).
PROFIBUS DP
master with DP V1
function
Cyclic communication with
PROFIBUS DP . State information is
exchanged (cf. appendix B.1).
The master may only send new commands to the slave (MOBY ASM) when the
ASM is ready. The MOBY ASM's readiness is indicated with cyclic state info. The
same applies to acknowledgments. The MOBY ASM may only fetch new
acknowledgments when a new acknowledgment is actually waiting (i.e., has not
yet been read). This information is also indicated with a state info.
Two indications are defined in the state info. The PROFIBUS DP master uses
these two indications to decide whether a DP/V1 telegram can be executed to or
from the MOBY ASM.
B-2
PROFIBUS DP/V1
MOBY ASM
MOBY ASM
Non cyclic communication with
PROFIBUS DP/V1. Commands and
acknowledgments are exchanged (cf.
appendix B.3).
J31069-D0155-U001-A0-7618
Other field
devices
FC 56