Connect 5 634-Displays


New member

im trying to connect 5 634-displays with an usb-seriell-adapter to a windows xp home edition pc. The first display works perfect, but its not possible to use more.

In the control panel I can see com3, until I plug in the next next display. After connecting, I see the comport of the new device with an exclamation mark.

How is it possible to connect more?!
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CF Tech

So you have:

COM1 (real serial port #1) => CFA-634 #1
COM2 (real serial port #2) => CFA-634 #2
COM3 (USB to serial adaptor #1) => CFA-634 #3

working, then adding one more messes things up?
USB LCD Displays - Graphic and Character LCDs with a Keypad


New member
No, I'm using only USB-Ports, my com1 isnt used. My displays have all USB-RS232-Adapter. The com3 is the first of these devices.

Sometimes, I get an errorcode 42. The driver for this hardware could not be loaded, because this device is already used on this computer. (translated from german)
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