- One SIMATIC S7-200 CPU
- One PC/PPI cable
- One programming device or PC
- One external CoBox Ethernet or CoBox standard (DIN) rail, price approximately 1100.00 DM
- One cable for the serial interface, for connecting the programming device or PC to the CoBox
- One twisted pair cable for connecting the CoBox to the network
Note! Starting with STEP 7-Micro/WIN Version 3.2.1, a Ethernet Wizard was added.
As a result, the new wizard now provides an easier method of programming this task than is shown here.
This tip shows how you can use the CoBox (made by the company Lantronix) with a SIMATIC S7-200 programmable logic controller. The modems connect an S7-200 CPU to a remote programming device or PC by means of Ethernet. In this way, you can program or monitor a remote CPU with STEP 7-Micro/WIN 32 version 3.0 by means of Ethernet.
| (Front view) Network Interface: | (Rear view) Serial Interface: | Standard (DIN) Rail CoBox Network Interface: |
| - RJ45 (10BaseT) and Attachment - Unit Interface (AUI) Ethernet | - DB25 RS-232/RS-422/RS-485 (channel 1) - DB9 RS-232 (channel 2) Note: Only the RS232 port was tested on this unit. | -10BaseT (RJ45) connection Serial interface: - RS-232/RS-422/RS-485 by means of terminal block or serial interface with RJ45 port Note: The RS-485 2-wire port did not function as of Feb. 2000. The RS232 port worked correctly. |
Firmware: version 3.6
Assigning Parameters to the CoBox
To assign parameters to the CoBox, you must put it into the configuration mode. The operator's guide tells you how to do this.
The following tables provide an overview of the parameters. (The operator's guide that comes with the device provides a detailed description, or you can find a description on the Internet under http://www.lantronix.com/
0 - Basic Parameters
The following table explains how to set the network-specific parameters and the password. Contact your network administrator for assistance in setting up the network parameters.
| Parameter | Setting | |
| Ethernet interface AUI (N) | (N) | |
| IP address | (000).(000).(000).(000) This address must be set to a unique value on the network. Contact your network administrator.(The CoBox operator's guide provides more information and examples.) | |
| Gateway IP address | The standard gateway must be set to the address of the router if you want to communicate with other LAN segments. If this is not the case, you can set 000.000.000.000 as the address. | |
| Net mask | Network mask, preset to the default network mask: Class A 8/24 | |
| Telnet Config password | You can set the password to prevent unauthorized access to the setup menu of CoBox. A password is not required for configuration by means of the serial interface. |
Channel-Specific Parameters
The following table explains how to set the channel-specific parameters for communication (such as transmission speed, interface mode, character frame).
| Baud rate | Transmission speed of the channel in question (up to 115 kbaud) | |
| Interface mode | RS-232C RS-485 channel 1 only RS-422 channel 1 only | |
| Flow control | 00 – no flow control 01 – XON/XOFF 02 – hardware with RTS/CTS lines 05 – XON/XOFF, for sending character to host | |
| Port number | Identifies the port for remotely initiated connections.The port number must be unique for each channel and must be in the range of 1 to 65535 (except for 0 and 9999). | |
| Remote IP address | If automatic connection setup is selected, a connection to this address is set up. | |
| Remote TCP port | For automatic connection setup, this parameter must also be set. When the parameter is set, a connection to the appropriate port number of the destination host can be established. | |
| Connect mode | Defines the behavior of the CoBox during connection setup and the reaction to connections coming in over the network. | |
| Disconnect mode | Termination of a connection 00 – Ignore the DTR signal. 40 – ActivateTelnet mode and terminal type. 80 – Disconnect by means of tapering DTR signal. | |
| Buffer flushing | Controls the handling of the line and network buffer during connection setup and connection clear down. In addition, it is possible to select between two pack procedures. | |
| Time-out | Time until the termination of the connection, if there was no activity to be recorded on the serial interface. | |
| Pack Cntl | Settings for the pack procedure that is waiting (00 – if no special functions are needed). | |
| SentChar | You can enter up to two characters in hexadecimal format. If one of these characters is received by the serial interface, it is sent immediately by means of the TCP/IP connection, along with the characters that are still waiting. | |
| (Telnet terminal type) | Only in the Telnet modeYou can use this parameter to indicate the terminal name. |
Sample Configuration
| CoBox Setup (PC Side) | CoBox Setup (S7 Side) | |
| Basic parameter: Ethernet interface AUI (N) | N | N |
| IP address | 194.039.078.244 | 194.039.078.245 |
| Gateway IP address | 000.000.000.000 | 000.000.000.000 |
| Net mask | 0 | 0 |
| Telnet Config password | <none> | <none> |
| Channel-Specific Parameter: | Channel 1 | Channel 2 |
| Baud rate | 9600 | 9600 |
| Interface mode | 7C = 01111100 RS-232C, 8 bits, even parity, 1 stop bit | 7C = 0111110011 bits communication |
| Flow control | 00 - - no flow control | 00 - - no flow control |
| Port number | 11244 | 11245 |
| Remote IP address | 194.039.078.245 | 000.000.000.000 |
| Remote TCP port | 12245 | 00000 |
| Connect mode | 16 = 00010110 - - Never accept connection - - Short message | C0 = 11000000 - - Always accept connection - - No connection setup |
| Disconnect mode | 00 - - ignore DTR | 00 - - ignore DTR |
| Buffer flushing | 00 | 80 = 1000000 - - pack procedure waiting |
| Disconnect time | 00:00 | 00:00 |
| Pack Cntl | 00 | 20 = 00100000 - - Immediately after sending out Send Character |
| SendChar 1 | 16 | 16 |
| SendChar 2 | 16 | 16 |
How to Connect the CoBox to the Programming Device/PC
Channel 1 on the PC side of the CoBox is connected to a serial interface of the PC and the Ethernet output of the CoBox is connected to the network. The baud rate of the serial interface of the PC must match the first channel of the CoBox.
As a standard, STEP 7-Micro/WIN uses a character frame of 1 start bit, 8 data bits, 1 parity bit (even parity), and 1 stop bit (11-bit communication). In this example, the transmission rate was set at 9600 baud.
How to Connect a Second CoBox to the PLC
Channel 2 of the CoBox on the side of the controller is connected to the controller by means of the PC/PPI cable and the Ethernet output of the CoBox is connected to the network.
To do this, you must set the parameters for the PC/PPI cable by means of DIP switches to a transmission speed of 9600 baud.
How to Set Up the Connection by Means of STEP 7-Micro/WIN 32 V3.0
- Start the STEP 7–Micro/WIN 32 V3.0 software.
- Select the menu command View 4 Communications (or click the Communications icon in the Navigation Bar).
- In the Communications Setup dialog box, double click the PC/PPI cable icon. The Set the PG/PC Interface dialog box appears. Go on to step 5.
If the Communications Setup dialog box does not show the PC/PPI cable icon, double-click the PC card icon or the top icon in the right-hand area. - In the Set the PG/PC Interface dialog box, select PC/PPI cable (PPI). If this selection is not in the list box, you must install it.
- Click the “Properties” button. The PC/PPI cable(PPI) properties sheet for your CPU and modem appears.
- In the Properties - PC/PPI cable (PPI) sheet, click the Local Connection tab.
- In the COM Port area, ensure that the Modem box contains a check mark. If the box is empty, select it to insert a check mark.
- Click the PPI tab. Set the transmission rate to 9.6 kbps.
- Click the “OK” button. The Set the PG/PC Interface dialog box appears.
- Click the “OK” button. The Communications Setup dialog box appears. There are now two modem icons and a Connect Modem icon.
- In the Communications Setup dialog box, double-click the modem under the icon of the PC/PPI cable (the modem on the PC side). The Modem Setup dialog box for the local modem appears.
- Select the “Add” button to configure your modem.
- Enter a name, such as "CoBox". Click OK. The Modem Setup box appears.
- Click the “Configure” button. The Configure dialog box appears.
- Make the following entries:
- Initialization String: AT
Communication String: ""
Prefix: ATD
Suffix: ^M
Hangup String: ““
Timeout: 5 - Click the Advanced button. The Modem Advanced Properties dialog box appears. Make the following entries:
- Command Processed Response: OK
Connect Response: Connect
Busy Response: Busy
Escape Sequence: +++
Communications Timeout: 750 - Click OK. The Configure box appears.
- To test the modem, click the Program/Test button. Click OK. The Modem Setup box appears.
- Click OK. The Communications Setup dialog box appears.
- To connect your modem, double-click the Connect Modem icon in the Communications Setup dialog box. The Dial dialog box appears.
- Enter the telephone number 245 (host portion of the IP address) and click the Connect button.
- Click OK. In the Communications Setup dialog box, test the communication by double-clicking the Update icon.
