Message Mapping - Agilent Technologies TwisTorr 305 FS User Manual

Technical Information
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 diagnosis activated) if the internal

serial link in not established
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 state (WAIT_PRM or
SRC_ADDR.

Message Mapping

The communication is based on the continuous data exchange capability of the
ProfiBus standard, where the master sends continuously the entire slave
configuration and reads back the entire slave status. For this purpose one Input
(from slave to master) and one Output (from master to slave) buffers are provided.
All the needed parameters are mapped inside each buffer.
The following tables summarise the ProfiBus parameter access, related to the
corresponding windows serial protocol (for this protocol please refers to the serial
interface paragraph).
The interface doesn't any scaling operation on the read/written parameters. It acts
only as a gateway between the ProfiBus network and the pump's controller serial
interface. As a consequence of this, the scale and the meaning of some parameters
depends directly to the specific model of Turbo Pump controller connected to the
interface.
248 Agilent TwisTorr 305 FS Remote Controller User Manual