PS/2 scanner on COM port using adapter

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This is a somewhat odd issue....

A client wants to use a hand held scanner, as by their standard using
a PS/2 plug. Not replaceable if anyone has that idea. Customer's

In order to get data from the scanner only and not mixed with the
keyboard, so we were wondering, is it possbile to use a PS/2 to COM
It works with a USB adapter, but then we dont know whether someone
typed it or got it from the scanner.

First extra power is needed, this is simple. The adapter does not give
much and the scanner needs 100mA.

Next, how does this work - the adapter simply translates the PS/2
synchronized data to async data?
In that case I should be able to read at 1200 baud, 7 bits etc.
So far it has not been possible.

Now, has anyone tried such tricks before?
It is possible to use PS/2 to COM adapter and read from the comport,
such as a mouse or keyboard?


Re: PS/2 scanner on COM port using adapter

Sonnich Jensen schrieb:
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I would use a keyboard which can be connected to USB. Scanner data over
PS/2, keyboard data over USB.


Re: PS/2 scanner on COM port using adapter
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There are two possibilities:
1. USB to PS/2, COM
2. USB to PS/2 plus PS/2 to COM

2. requires two chips, one active USB to PS/2 and one active PS/2 to
1. requires one chip and a passive PS/2 to COM connector.

I don't have to tell you what most bean counter would do in building
them.  In that case, the passive PS/2 to COM connector would be
useless by itself.

Re: PS/2 scanner on COM port using adapter
On Tue, 27 Sep 2011 06:59:07 -0700 (PDT), Sonnich Jensen

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If you are thinking of adapters that are included with computer mice,
then no, it is not possible. Those adapters are made for each specific
model of mouse, and may or may not work with another model.

The adapters are simple, passive devices. Support for serial or PS/2
is provided by the mouse firmware. A mouse that is not made
specifically for serial port use, will not work with an adapter.

You would need to design (or find) a device that decodes the PS/2 data
stream and converts it to async serial. A microcontroller or something
similar would probably be needed.

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