Requirement for Proper Connection of Data Loggers to Modems and Ethernet Devices

The SmartReader Plus data logger must be powered correctly for proper communications and to maintain its internal battery life.

The logger receives power through the IC-101 interface cable when it is connected to the PC. The IC-101 powers the logger by asserting (placing a positive voltage on) the RS232 control lines RTS and DTR. To ensure that the logger is powered correctly when it is connected to a different device like a Ethernet to serial converter or a wireless modem, you must assert the equivalent control lines on the device you are using. The PC is considered a DTE (Data Terminal Equipment) device and uses RTS (Request To Send) and DTR (Data Terminal Ready) on pins 7 and 4 to power the logger.

If the device you are using is a DCE (Data Communication Equipment) then CTS (Clear To Send) and DSR (Data Set Ready) on pins 8 and 6 are control lines that must be asserted. If the device you are using is a DCE then a null modem adaptor must be used with the IC-101. (The RFA 100 cable is available for use instead of the IC-101 which eliminates the need for the null modem adaptor) The above pin numbers refer to a RS232 9-pin connector.

Consult the device manual or contact the manufacture of the device to determine whether the device is acting as a DTE or a DCE. DTE’s normally have a male connector whereas a DCE will normally have a female connector, but this is not always the case. Therefore, it best to consult the device documentation.