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Siemens Fetch/Write master
Siemens Fetch/Write protocol PLC address read and write driver
Open the plugin
Enter “Development Configuration → Collection Configuration”, create a device and select “SiemensFetchWriteMaster” in “Collection Plugin”.
Supported channels and data types
| Channel type | Pre-configuration check |
|---|---|
| TCP Client | Confirm network reachability of the device IP, port, and gateway to the device. |
Optional data types: Boolean, Byte, Int16, UInt16, Int32, UInt32, Int64, UInt64, Float, Double, String
This list describes types allowed by the plugin editor. Address width, arrays, string length and read/write restrictions still follow this page; it does not mean that every address supports every type.
This plugin supports only the TcpClient channel. The defaults are ABCD data order and a 200-byte maximum pack size; configure common timeout, retry, and write-priority fields through Collection Configuration.
Address rules
- Fetch/Write addresses support I, Q, M, DB, T, and C, with decimal byte offsets; for example,
DB20.100. Boolean must explicitly use byte.bit, such asM100.3, and is implemented through byte read-modify-write. The I area is read-only, DB/T/C access lengths must be even, and the current version supports TCP clients only.
Device debug
Enter “Development Configuration → Collection Configuration”, select the current device then open “Protocol Debug” at the top of the workspace.
Read and write
Perform read or write verification according to the current plugin address rules; confirm on-site security and permissions before writing.
Messages
Check the device’s message sending and receiving and protocol logs to locate message format, connection and parsing problems.
Functions
| Function | Purpose |
|---|---|
| Read and write | Read a confirmed point and write only to an approved test point. |
| Messages | View sent and received frames, protocol fields, and error details. |
Verify the configuration
Monitor DB20.100 online in the PLC engineering tool, compare its value with the gateway variable and confirm advancing sample times.
Troubleshooting
- Align DB/T/C access on even bytes; I is read-only. Fetch/Write differs from S7 and may require a different port.
Related links
- Collection configuration: View channel, device and common variable configuration.
- Plugin Index: Find other collection or data-forward plugins.