Technical data

Description of the Architecture
Introduction to PROFIBUS on Industrial PC
C79000-G8976-C068
17
3.5.2 FMS Programming Interface
The Siemens implementation of the FMS programming interface is
known as SAPI-FMS.
The acronym SAPI-FMS stands for:
•
SAPI -
S
imple
A
pplication
P
rogrammers
I
nterface
•
FMS -
F
ieldbus
M
essage
S
pecification - the layer 7 communications
protocol of PROFIBUS.
SAPI-FMS
•
represents a simple C programming interface,
•
provides access to the FMS services on PCs and PGs and
•
is available as a C library and is operated with SIMATIC NET drivers
and SIMATIC NET communications processors.
The SAPI-FMS programming interface has the following advantages:
•
SAPI-FMS is a simple but flexible and powerful interface.
•
The SAPI-FMS programming interface uses asynchronous
procedures.
•
SAPI-FMS handles sequential services such as the transfer of a
communication relationship list automatically.
•
SAPI-FMS converts variable data automatically into the format of
the local CPU.
•
SAPI-FMS supports troubleshooting with an integrated trace
function.
•
The SAPI-FMS programming interface is compatible with other
SAPI programming interfaces.
•
The SAPI-FMS programming interface can also be used by other
programs, for example BASIC or Pascal programs.
SAPI-FMS
What Does SAPI-
FMS Mean?
What Is SAPI-FMS?
Advantages of the
SAPI-FMS
Programming
Interface