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Electronics => Projects, Designs, and Technical Stuff => Topic started by: jz79 on September 27, 2023, 05:50:54 pm

Title: RFID 125khz cards, RDM6300 reader trying to make sense of the readings
Post by: jz79 on September 27, 2023, 05:50:54 pm

edit: simplified my question

A card that came with the reader has the ID printed on it: 0008075634  [empty space] 123,14706
and this card reads as following using the RDM6300 reader:
-------------------------------------------------
6F007B39725F {this is the serial string, and the following is interpretation by uC, arduino running a demo sketch for this reader}

Message-Head: 2
Message-Data (HEX):
6F (version)
007B3972 (tag)
Message-Checksum (HEX): 5F
Message-Tail: 3
--
Extracted Tag: 8075634
Extracted Checksum (HEX): 5F (OK)
---------------------------------------------------

and I'm interested what is the relation between the decimal value (or its hex value that the reader is sending over serial) to the latter decimal number printed on the card - this 0008075634(007B3972)  and this 123,14706 ?

Title: Re: RFID 125khz cards, RDM6300 reader trying to make sense of the readings
Post by: jz79 on September 28, 2023, 09:29:11 am

nvm, figured it out, didn't realize significance of the comma in the second "number"
RDM6300 hex string:           00 7B         39 72
                                             ^               ^
second number on card:      123            14706