Why I'm getting this message: "Interface cannot be used (error 229)" I've plugged an USB NFC/RFID reader, model ACR112U-A9 provided by ACS Ltd.

Although it is plugged I can't read anything and I keep getting this logs in console:

09/06/15 14:13:00,901 com.apple.SecurityServer[83]: reader ACS ACR122U PICC Interface: state changed 16 -&gt; 34
09/06/15 14:13:00,902 com.apple.SecurityServer[83]: token in reader ACS ACR122U PICC Interface cannot be used (error 229)
09/06/15 14:13:01,249 com.apple.SecurityServer[83]: reader ACS ACR122U PICC Interface: state changed 32 -&gt; 18


How can I solve this issue? Do you know what is the error 229 and why it's triggered?
I found a solution: You need to download the ACS ACR122U Drivers for Mac OS X 10.x.

Here the download page and the direct link for PC/SC Driver Installer 1.1.0 (Mac 10.5, Mac 10.6, Mac 10.7, Mac 10.8, Mac 10.9, Mac 10.10) (2014-09-17 306KB).

You have to install it even if the installer is not properly signed.

It will install the useful driver in: /usr/libexec/SmartCardServices/drivers/ifd-acsccid.bundle

Now you are able to use the card reader.
If you want to test it out, I made a simple project here.