West Control Solutions KS 800 Profibus Interface Manual - Manual (Page 17)

3.5.2 General communication structure
For transmission of the parameters required for the function block protocol via an 8-byte data window, the
access is composed of three parts:
w Order header with specification of code, FB no., fct. no., type and the following real and integer values.
Start telegram structure:
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
ID ID1 Code FB no. Fct._no. Type Numb.real values Numb.integer values
w n data blocks with the data to be transmitted
Data telegram structure:
Transmission of real data as fixedpoint and of integer values
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
ID Count Integer
w An end block provides the operation result
Structure of the end telegram:
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
ID Result
Signification of result
0 OK
4 NAK
The read or write operation is always started by the master. With the number of real and integer values ≠ 0, a
write service, otherwise, a read service is started.
The code determines the access type:
Code < 100, no multiple of 10 Ä individual access
Code < 100, multiple of 10 Ä tens block access
Code > 100 Ä overall block access
3.5.3 Data write sequence
Start telegram:
Master sends: Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
0x10 ID1 Code FB no. Fct._no. Type Numb.real values Numb.integer values
Controller
replies:
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
0x10
Data telegrams:
Master sends: Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 - 7 Controller replies: Byte 0 Byte 1 Byte 2 Byte 3
Byte 4 - 7
0x68 count Value 0x68 count
Thereby, the first value is sent with Count = 1. For flow control, Count is reflected by KS800 (? once). The
values are transmitted in the order real - integer.
End telegram:
Master sends:
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 - 7 Controller replies: Byte 0 Byte 1 Byte 2-3 Byte 4 - 7
0x16 0x16 Result
Process data
17 9499 040 50511