NDC BETA LaserMike LaserSpeed Pro 8500-4, Instruction Handbook Manual

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LaserSpeed Pro 8500-4 Instruction Handbook:
Profibus DP™
11-7
The Profinet IO master provides an incrementing enumeration index within the command qualifier field. Usu-
ally this would begin with an enumeration index of 0, and increment after each successful enumeration ex-
change. Enumeration is complete when the response code is set to “unknown item.”
For a successful enumeration, the gauge sets the PKW response data as follows:
Bit: 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Word
2:
Database Item Identifier
Word
3:
Database Item Access Flags Database Item Type
Database Item Identifier: identifier to be used with other database services
Database Item Type: 0=long, 1=float, 2=string, 255=unknown
Database Item Access Flags: 0x01=non volatile, 0x02=read-only, 0x04=constant (not changed by gauge)
11.3.5 PKW Read Long (Command Code 4)
This command allows an integer database item to be read.
The Profibus master specifies the database item identifier within the command qualifier. If the referenced
databas
e item is not an integer, then the response code will be set to “wrong type.”
The gauge will ignore the contents of the PKW Request Data. The PKW Response Data will contain the
signed 32-bit value read from the database.
11.3.6 PKW Write Long (Command Code 5)
This command allows an integer database item to be written.
The Profibus master specifies the database item identifier within the command qualifier. If the referenced
database item is not an integer, then the response code will be set to “wrong type.”
The contents of the PKW Request Data are treated as a signed 32-bit number to be written in to the data-
base, and the PKW Response Data will be all zeroes.
11.3.7 PKW Read Float (Command Code 6)
This command allows a floating-point database item to be read.
The Profibus master specifies the database item identifier within the command qualifier. If the referenced
database item is not floating point, then the response code will be set to “wrong type.”
The gauge will ignore the contents of the PKW Request Data. The PKW Response Data will contain the 32-
bit floating-point value read from the database.