Using the 6500 RS232 Diagnostic Plug

5/1/09

Almost all computer connection problems are found on the computer end of the connection. That is, the computer has a malfunctioning COM port, the driver for a USB-to-RS232 converter is not functioning properly, or the COM port has not been set correctly in the FONIX software program. However, occasionally there may be a problem with the 6500 itself that is causing the RS232 connection problem. The 6500-CX has two levels of built in RS232 diagnostics to determine RS232 issues with the analyzer.

The first level is run every time the instrument is turned on. The analyzer checks the UART, and displays the message “RS232: AVAILABLE” on the third line of the Opening Screen on the analyzer if all goes well. If a problem is found with the UART, the message, “RS232: BAD UART” will be displayed. If you see this error message, you should contact Frye Electronics since you probably have defective hardware.

The second level of diagnosing uses a silver, cordless plug that is included with every 6500 RS232 Option package. Unplug the computer connection on the back of the 6500 and insert this silver plug into the RS232 connector. Turn off the analyzer and turn it back on to run the diagnosis. This test checks the UART more completely, checks the RS232 driver chips, the cable from the rear panel DB25 connector to the I/O board, and the RS232 interrupt. After the tests are run, one of three messages will be displayed:

RS232: DIAGNOSTICS PASSED: All tests passed successfully

RS232: NO INTERRUPT: The interrupt jumper is missing, incorrectly plugged in, or if the trace on the back of the board is not cut.

RS232: BAD CABLE: The cable from the I/O board to the rear panel is plugged in backward.

After this diagnosis is run, it is recommended to unplug the diagnosis connector and turn on and off the analyzer again before proceeding with measurements.

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