I have a USB desktop reader "ACR1281U" which is a basic keyboard emulation reader. When you "swipe" the card it'll output it's ID and run a ENTER-command.

When I plug this into my Raspberry Pi it'll work from time to time with 1-2 swipes and sometimes it doesn't work at all. This is with all default drivers - I haven't installed anything else then just input the USB-device into my R-Pi.

First I thought that the official driver from ACS could/would solve this so I went to their website http://www.acs.com.hk/en/driver/36/acr128u-dual-interface-smart-card-reader/ but found out that they only have their driver (.deb) package as i386 and amd64.

Do I really need to official driver or can I somehow troubleshoot my device as it is now? When I boot up I can see that the RPi detects the correct USB device on input. Is there something I can do to troubleshoot this further?


  • 1
    Could this be a power supply problem? Maybe the R-Pi doesn't have the juice to power the USB-device on it's own? Nov 13, 2014 at 16:04
  • adding to the comment above how is it connected to the Pi? Have you tried connecting it through a powered hub? Nov 13, 2014 at 17:56
  • Right now it's just connected to one of the standard 2 USB ports. I'll try and get a powered hub today and see if that'll help with the power supply to rule that out. Thank you. Nov 14, 2014 at 9:59
  • I got a D-Link DUB-H7 USB hub and I can see during the R-Pi load screen that it detects the 5-port hub but for some reason my connected devices (like the Reader) doesn't work at all (it's not lit/powered). Can there be a problem with the USB-hub? Can I troupleshoot that or should I order this instead shop.pimoroni.com/products/pihub? Nov 14, 2014 at 10:56
  • It was the USB power supply! I got another one with different voltage and now it's working perfectly. Nov 14, 2014 at 12:11

1 Answer 1


The RFID card reader can't be powered by the R-Pi but needs it's own power source. Connecting the reader through an externaly powered USB-hub will make the reader work.

  • What version of the Raspberry Pi were you using?
    – zundi
    Jul 31, 2015 at 19:14

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