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Advant Controller AC 31 / Issued: 01.99
6 – 7
Communication
3
The MODBUS
®
frames transmitted by the master contain the following information:
- The MODBUS
®
address of the interrogated slave (1 byte)
- The function code defining the master request (1 byte)
- The data to be exchanged (N bytes)
- The CRC16 control code (2 bytes)
The frame has a maximum total length of 240 bytes, thereby enabling the exchange of a
maximum of 100 data words or 255 binary data.
The slave’s reply contains the request confirmation, the data to be returned and also a frame
control code. The slave returns an error code in the event of an error.
Further information on protocols can be found in the appendix.
Only the following MODBUS
®
operation codes may be processed by the 40 and 50 series
basic units:
Function codes (Hex)
Description
01 or 02
Read n bits
03 or 04
Read n words
05
Write a bit
06
Write a word
07
Rapid read of 8 bits
08
Diagnosis/initialization
0F
Write n bits
10
Write n words
The following codes are generated in the event of an error:
Error codes
Description
01
Unknown function code
02
Address error
03
Data error
Содержание 07CR41
Страница 6: ...Contents 4 Advant Controller AC 31 Issued 08 99 3 ...
Страница 58: ...Installation 4 10 Advant Controller AC 31 Issued 08 99 3 Figure 16 Relay outputs Figure 17 Transistor outputs ...
Страница 62: ...Installation 4 14 Advant Controller AC 31 Issued 08 99 3 Figure 22 Extension XK 08 F1 l ...
Страница 94: ...Programming 5 22 Advant Controller AC 31 Issued 01 99 3 ...
Страница 110: ...Communication 6 16 Advant Controller AC 31 Issued 01 99 3 ...
Страница 122: ...Appendix A 4 Advant Controller AC 31 Issued 08 99 3 ...
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