Please provide some instructions.
There are many different types of RFID tags with rewritable memory, so it would not be possible to provide specific instructions. Generally speaking, companies that manufacture readers typically offer an application allowing a user to encode a serial number in a transponder and/or to write data to a user memory block. Typically, the serial number is locked after it is encoded. It might be locked permanently, or you might be able to send a code to unlock the memory and write a new serial number.
Depending on the chip used and the standards with which that chip complies, you might be able to lock user memory, either permanently or temporarily. If memory is unlocked, then you could choose the user memory block in your reader’s application, enter the information you want to store and then write it to the transponder’s user memory. If the memory is locked, you would first need to unlock it with a serial number before writing new memory to that block.
I would encourage you to read the Electronic Product Code (EPC) documents available on GS1‘s website regarding the EPC Gen 2 and EPC Gen 2 V2 air-interface protocol standards. These papers explain how to write to and lock memory. You might also want to search the Web for the manuals of some leading RFID readers on the market.
—Mark Roberti, Founder and Editor, RFID Journal
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