Software Operation And State Machine - Agilent Technologies TV 301-P Bedienungshandbuch

Software operation and state machine

From the software point of view, the interface can be
seen as two devices (one for ProfiBus and the other for
the internal link) linked together.
Each device has its own state machine to manage the
device operation.
PROFIBUS STATE MACHINE
Status
POWER_ON Interface set-up
WAIT_PRM Wait for parameterisation from the master
WAIT_CFG Wait for configuration from the master
DATA_EX Regular data exchange
Meaning
INTERNAL LINK STATE MACHINE
Status
POWER_ON Interface set-up
SRC_ADDR Search for the controller serial address
IDENTIFY Identify controller model and protocol
DATA_EX Regular data exchange
The two machines continuously share I/O data with the
relative bus, and interact each other only in following
conditions:
•
ProfiBus Data Exchange is suspended (static diag-
nosis activated) if the internal serial link in not es-
tablished
Internal serial link Data Exchange is suspended
•
(only for output data) if the ProfiBus State machine
is not in Data Exchange mode
As a general rule, unrecoverable communication errors
make each machine to jump to the state immediately
following the power-on
SRC_ADDR)
45
TECHNICAL INFORMATION
Meaning
state (WAIT_PRM
87-901-001-01 (A)
or