USB vs RS232

Matthias Gross

.Registered Member
In the past I had been asked for the reason why we have RS232 as a standard "on board".

There are a lot of reasons, let me explain.

1. RS232 is more reliable
The old-fashioned RS232 interface (I think that this standard is now more than 30 years old) is very reliable and stable in operation. You will never have a problem with a driver or hardware conflicts like you can have with USB. Most industry applications work with RS232, not with USB.

2. Our RS232 is not only used for the PC-connection
We use this interface for the initial firmware upload and for testing and hardware diagnosis. This interface is also used to communicate with the ProfiLux View (the external display) and to supply the View with +12V power. Furthermore the SMS-controller (coming soon) will be connected there. Using a USB-interface is possible in principle for these things, but much too complicated and too expensive - and not 100% reliable.

3. ProfiLux can be equipped with USB
You can insert a extension card "PLM-USB", then you have RS232 AND USB, both interfaces work independently.

4. A cheap USB-RS232-converter can be used
For some $ or Euros you can obtain a converter.

I think now comes the question why we don't have both interfaces as a standard on board or why we don't ship a converter with each ProfiLux.
Answer: This would be addititional costs for the customer. Why should a customer who doesn't want or need USB (maybe he has LAN or his PC has RS232) pay for this?
We always have to keep the benefits AND costs for the customer in mind because we want products which are up-to-date AND affordable!
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New member
You can purchase a USB-RS232 converter in Canada / US for anywhere between $20 - $60. I think I paid $30 for mine.