graphing program

[mark]

not fish related but thought ask here

Wondering if anyone knows of a Windows utility would interrogate a device over a serial line for a valve then plot the valve on a graph over time.

What this is for is to create something like a paper barograph trend on a computer monitor. Our IT people have been brushing off the request for years and I'm getting a little frustrated maintaining 50 year old mechanical clocks when I have a digital barometer with a serial port sitting beside a XP computer. Have contacted the barometer supplier and though they have a utility that will do this, out model isn't supported.