Beckhoff BC9100 User Manual

Fieldbus system
BC9000 and BC9100 69Version: 4.0.0
Query
Byte name Sample
Function code 3
Start address high 8
Start address low 0
Count high 0
Count low 2
The fieldbus coupler answers with byte count 4, i.e. 4 bytes of data are returned. The query was for two
analog channels, and these are distributed over two words. In the analog output process image, the first
channel has the value 0x3FFF, while the second channel has the value 0x0.
Response
Byte name Sample
Function code 3
Byte count 4
Data 1 high byte 63
Data 1 low byte 255
Data 2 high byte 0
Data 2 low byte 0
7.5.4.5 Read input register (Function 4)
The function Read input register reads the inputs on a word basis.
In this example the first two analog inputs (or the first two input words) are read. The analog inputs (or input
words) start at an offset of 0x0000. The length indicates the number of words to be read. A KL3002, for
example, has two words of input data.Therefore, the length to be entered at Number low is two.
Query
Byte name Sample
Function code 4
Start address high 0
Start address low 0
Count high 0
Count low 2
The fieldbus coupler answers with byte count 4, i.e. four bytes of data are returned. The query was for two
analog channels, and these are now distributed over 2 words. In the analog input process image, the first
channel has the value 0x0038, while the second channel has the value 0x3F1B.
Response
Byte name Sample
Function code 4
Byte count 4
Data 1 high byte 0
Data 1 low byte 56
Data 2 high byte 63
Data 2 low byte 11

Beckhoff BC9100 Specifications

General

Brand	Beckhoff
Model	BC9100
Category	Controller
Language	English