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RDM6300 RFID reader~

This feature is included only in tasmota-sensors and tasmota32 binaries

When compiling your build add the following to user_config_override.h:

#ifndef USE_RDM6300 
#define USE_RDM6300         // Add support for RDM6300 125kHz RFID Reader (+0k8)

RDM6300 125KHz cardreader mini-module is designed for reading code from 125KHz card compatible read-only tags and read/write card.


There seems to be an issue with some card readers!(the cheap ones?) These output some fake/ghost readings that look like valid card numbers and validate thru the XOR method but are not real. This is confirmed by multiple users. Please see details in issue #9952. There seem to not be issues yet with SeeedStudio Grove 125Khz Reader or RDM630


Sensor uses serial interface for communication.


Pin3 unused

Tasmota Settings~

Update 12.10.2020: Seems there is a new driver and you can use RDM6300 RX instead of the SerBr Tx and SerBr Rx. This also seems to show the last card read in the management interface. As a note, the card number that comes from the SerBr was 12 chars and the RDM6300 one has only 8, being stripped by the first 2 and last 2 chars.

In the Configuration -> Configure Module page assign:

  1. GPIOx to SerBr Tx (71)
  2. GPIOy to SerBr Rx (72)

If the RFID Tag is held in front of the Antenna the reader starts sending the Tag ID. The Tag Id is prefaced with a 0x02 and the end is delimited with a 0x03. If the reader reads the tag multiple times you would get one line with multiple times the Tag ID. For this to separate you can add a SerialDelimiter of 0x03. This will split the result from the serial into several single mqtt messages. But (probably) all the messages wil be prepended with a binary 0x02.

Set SerialDelimiter to 3

SerialDelimiter 3



// tele/sonoff-rfid-1/RESULT {"SSerialReceived":"01020304FAFA"}
String RFID_1      "RFID [%s]"

Breakout Boards~