I've seen a few articles where people have integrated CueCat and AVRs
using Arduino IDE.  Comments on one [1] mention how there are
different builds of the CueCat, and they didn't always follow
standards.

My guess is that your inexpensive converter doesn't follow the PS2
standards in the exactly the same way that the CueCat doesn't follow
them.

You might hunt around for articles like that, and dig into the
interface some more.

Or cut the cable off and interface directly.

References:

1.  http://www.instructables.com/id/Arduino-and-CueCat-barcode-scanner/?ALL=
STEPS
    (undated, probably 2012)=20

--=20
James Cameron
http://quozl.netrek.org/
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