SpringCore RDR MK1 Protocol

SpringCore devices configured for Smart Reader operation support using the SpringCard ‘MK1’ legacy protocol to communicate over serial channels.

Warning: only a partial implementation of the ‘MK1’ protocol is available in the SpringCore devices. Pay attention to all the specificities exposed in the following sections.

Channels supporting the MK1 protocol

MK1 protocol has to be enabled by setting appropriate value to 03 in register 02A0

MK1 Messages, device to host

Startup Message

When configured to use the MK1 serial protocol, upon startup, the reader sends its name prefixed by # and followed by /RDR, for instance

# M519/RDR

This let the host know that the reader is ready, or has rebooted for any reason.

Warning: upon startup, earlier IWM2 devices send the manufacturer name and their version (e.g. SpringCard K663/RDR 1.21); SpringCore don’t send their manufacturer name nor their version, and a # sign is added as prefix.

Card Event Message

Everytime the Smart Reader reads a tag (contactless card, NFC tag or RFID label, data coming from a BLE token…), it sends to the listening host(s) an MK1 Card Event Message, formatted as follow:



  • The PREFIX and the SUFFIX fields comes from the Template
  • BEGIN MARKER is the plus sign (+)
  • END MARKER is <CR><LF>

Warning: unlike earlier IWM2 devices, BEGIN MARKER and END MARKER are constants of the SpringCore devices and can’t be changed by configuration.

MK1 Messages, host to device

Warning: unlike earlier IWM2 devices, SpringCore devices don’t accept any MK1 message in the host to device direction.