Topologies of SIMATIC NET PROFIBUS Networks

Uses

The PROFIBUS-DP/RS-232C link is a converter between an RS-232C (V.24) interface and PROFIBUS-DP. Devices with an RS-232C interface can be linked to PROFIBUS-DP with the DP/RS-232C link. The DP/RS-232C link supports the procedures 3964 R and free ASCII protocol.

Master

 

 

 

 

Configuration

 

 

 

 

with STEP 7

S7-400

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PROFIBUS-DP

SIEMENS DP/RS-232C Link

RS-232C

Serial procedure

PROFIBUS LAN cable

Device

Figure 2-19 Example of a Configuration with DP/RS-232C Link

How the DP/RS-232C Link Works

The PROFIBUS-DP/RS-232C link is connected with the device over a point-to-point connection. The PROFIBUS-DP/RS-232C link converts to the PROFIBUS-DP protocol. Consistent data are transferred in both directions. A maximum of 224 bytes of user data can be transferred per frame.

PROFIBUS Networks SIMATIC NET

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6GK1970-5CA20-0AA1 Release 2 05/2000

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Siemens SIMATIC NET PROFIBUS manual How the DP/RS-232C Link Works, Device