(Ruby) PC/SC Get Card UID

See more SCard Examples

Sends the APDU command to get a card's UID.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

scard = Chilkat::CkSCard.new()

# First establish a context to the PC/SC Resource Manager
success = scard.EstablishContext("user")
if (success == false)
    print scard.lastErrorText() + "\n";
    exit
end

# Use your own smart card reader name here.
success = scard.Connect("ACS ACR122 0","shared","no_preference")
if (success == false)
    print scard.lastErrorText() + "\n";
    exit
end

print "Connected reader: " + scard.connectedReader() + "\n";
print "Active protocol: " + scard.activeProtocol() + "\n";
print "ATR: " + scard.cardAtr() + "\n";
print "Reader Status: " + scard.readerStatus() + "\n";

#  Send the APDU command 0xFF, 0xCA, 0x00, 0x00, 0x00
bdRecv = Chilkat::CkBinData.new()
success = scard.TransmitHex(scard.activeProtocol(),"FFCA000000",bdRecv,32)
if (success == true)

    print "Received: " + bdRecv.getEncoded("hex") + "\n";

    # The UID is the returned data without the final 2 bytes.
    numBytes = bdRecv.get_NumBytes()
    if (numBytes > 2)
        print "UID: " + bdRecv.getEncodedChunk(0,numBytes - 2,"hex") + "\n";
    end

else
    print scard.lastErrorText() + "\n";
end

# Disconnect from this reader.
success = scard.Disconnect("leave")
if (success == false)
    print scard.lastErrorText() + "\n";
end

# Applications should always release the context when finished.
success = scard.ReleaseContext()
if (success == false)
    print scard.lastErrorText() + "\n";
end