Alicat PROFIBUS User Manual
Page 7
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4.3.2.3 Command
The command consists of four octets — where the first two octets are the
command and last two octets are the data that applies to the command. Both the
command and data are 16 bit unsigned integers that are in big endian format.
Current commands are:
Command
Action
0 (0x0000)
Do Nothing
21 (0x0015)
Change P in PID loop
22 (0x0016)
Change D in PID loop
23 (0x0017)
Change I in PID loop
46 (0x002E)
Change Gas Select
65 (0x0041)
Change Power Up Set-point Configuration
Note: Command values not listed in the above table are reserved for factory
use only and can cause undesired effects if utilized.
For the data bytes the following are valid:
Valid Values
Data Type
0 to 65535 (0x0000 to 0xFFFFF)
PID Parameters
0 to 29 (0x0000 to 0x001D)
Gas Parameter
0, 32768, or 49152 (0x0000,0x8000,
or 0xC0000)
Power Up Set-point
Configuration
Description of power up set-point configuration bits:
Valid Values
Meaning
0 (0x0000)
Unit will go to zero set-point at power up or loss of
Profibus communication.
Also the unit will respond to set-points given over the
Profibus
32768 (0x8000)
Unit will maintain last set-point saved to
nonvolatile memory at power up or loss of Profibus
communication (see section 4.3.2.2 Control
Register)
49152 (0xC000)
Same as 32768 with the addition that unit will ignore
Profibus set-points.