Dynasonics TFXP Series Transit Time Ultrasonic Flow Meter - Manual (Page 112)

TFX Communications Using UltraLink
The current implementation of the UltraLink software utility was originally developed for Windows
95, Windows 98, and Windows 2000 using a standard RS-232 port. These operating systems left
the choice of serial ports much more in the users hands. The physical connection was also the
age-old DB-9 serial connections found on all computers of the time.
With the introduction of Windows XP using USB serial ports inputs connections became a little
more troublesome. Windows XP (using the plug and play paradigm) give the user far less control
over how the USB ports are parceled out. The ports are also reconfigured dynamically depending
on the actual devices connected to the computer at the time. The effect of this port re-distribution
is that a port and device pair that worked yesterday may not work today without adjustments.
Physical Connections for UltraLink
Dependent on the model of ultrasonic meter UltraLink can communicate using three physical
connections.
For entry level meters, TFXL, HTTF, and PTTF a dedicated cable is needed to mate with the
communications port on the circuit board.
The output from this port is a TTL level signal that must be converted to signal levels suitable for
RS-232 communications so a TTL to RS-232 converter is required.