This tutorial is intended as a supplement to the original user manuals. Therefore, us it to familiarise yourself with the project and not as a complete guide to installation.
Westermo's TD-32 11 bit industrial modem is a "revision" of the TD-22. TD-22 had a maximum transmission rate (transfer) between 2400 baud, and a maximum communication speed of 19,200 baud. On the TD-32 the transmission rate is increased to 14,400 baud whilst the communication speed is increased to 57,600 baud. This is the most important difference between these two modems. Otherwise, there are no obvious differences in the factory settings, either on the dip switch (switches) or AT commands. The earlier versions of TD-32 had a fault within the program. This problem effected the dip-switch true reading. This was highlighted by the importer (LMC). On later versions, this is corrected. If in doubt, contact the importer to receive the current EEPROM (program).
2 procedures for setting up Westermo TD-32
- Start up the hyper terminal on the PC.
- Connect with = Direct to COM1 (or another serial port)
- Configuration = 9600, 7, Equal, 2, No (baud rate, databit, parity, stop bit, flow control)
- Connect to the modem on the COM port 1 ( the same port that is used in the hyper-terminal) and select "connect" in the menu. The modem does not need to be connected to a phone line. The protocol is the same one that the hyperterminal is set to.
- Set up the modem with the following commands on the factory dip switches:
AT Checks if the modem is connected.
AT & F Retrieve the modem settings.
AT & A1 ignore data on the serial port during the connection.
AT & D0 Indicates use of DTR.
(AT & K0 Indicates use of flow control / fix .*)
ATF8 User fast 9600 baud. (as a test this was wrong, but the modem works fine without)
ATS0 = 1 Auto answer on the first ring.
AT & W Save / layout of EEPROM.
Each entry provides an OK response from the modem in the hyper terminal window.
- TD-32 can be set up by setting the dip-switch configuration before it is connected to the power, or the default factory settings can be used. For the factory settings all of the switches apart from SW3: 1 are set to OFF. Set SW3: 1,7 = ON, SW4: 2,3,5,8 = ON, SW5: 4 = ON. The remaining dip switches should be set to OFF. This configuration provides the same setup as the hyper terminal is set up to (in the above procedure) and means the modem is now initialized / set up.
*It is not necessary to connect pins 4 and 5 on the modem respectively with pins 4 and 5 on the PLC. For bad telephone lines try connecting without this command so that the modem checks the transferred data. Remember to ensure your PC modem is set with with the same data communications. This is especially true if you use CxProgrammer. The following command responses are given by the connection between the modem (or hyper terminal Syswin):
CONNECT 9600/REL - LAPM (or - NMP) This is tested against both ports, both on a CQM1-CPU43 and a C200HX-CPU64.