Chemistry Electronics Services
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LASER PARALLEL PRINTER ERROR/INCOMPATIBLITIY ON PERKIN-ELMER RX-1 FTIR SPECTROMETERS

We found that this FTIR spectrophotometer is only compatible with certain (very old) laser printers. At first we thought this involved an issue with the printer's PCL command set, and the HP-GL/2 plotter language. Nope. Intstead I discovered that the instrument has an apparent design problem on its parallel port: it ignores the "BUSY" pin and just keeps sending data to the printer. The printer then freezes up, leaving the "BUSY" pin high. All of our RX-1 units do it. So do older 1600 FTIRs. This doesn't cause problems when using the old HP-1200 laserjet. But on our modern printer (HP P2035 and others) equipped with a centronics-type parallel port, this behavior causes the printer to lock up and require a power-off to reset. So, unusuable.

I tried adding an LPT-to-USB smart cable module, then tested on a couple of modern USB laserprinters. WORKS! Perkin-Elmer sells the following for $220: L1180007. I find an identical one online for much cheaper: LPT2USB is a $70 converter to "allow modern printers to be used with Centronics parallel LPT port found on old instruments." We tested the PE product and the LPT2USP product, and both seem identical (both solve the problem.) And here's another similar product for modern PCL printers, $95 from Aknord [Still haven't tried that one.]

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