How to read and write Gen 2 RFID tag data

Some Gen 2 RFID tags contain a 96-bit EPC capacity, which can just fit an electronic product code as the unique identifier of the product, and other information must be placed in an external database associated with the EPC. Other tags are 96-bit, 128-bit and 256-bit, so the data can be stored directly in the tag.

For example, the label affixed to the perishable cargo bag can write the shelf life and batch number of the product; the label affixed to the shipping container can write the mailing address of the consignee; the label affixed to the aircraft parts or the pipeline valve Compile the maintenance record, and the record can be written into the label’s user memory for each inspection.

As long as user memory is established, you can effectively read and write tag data, but this is not easy, so it is very important to find an experienced software supplier or system integrator, they need to have the ability to solve the following problems.

There is a 16-bit program block stored in the user, you need to decide which data is stored in which block, and then you have to configure the software that controls the reader-whether it is intermediate software or an application installed in the reader , So that it can decide which data to access according to the program. The “layout” data is very important in user memory, because the arrangement will affect the performance. The reader needs to send commands to the tag to access the user’s memory, which is time-consuming and slows down the reading speed.

Due to limited user memory space, compressed data is also necessary. The general ISO 15962 standard provides several compression methods, but each has to be discarded-among them, space and performance can only choose one. If an application needs to read all the data at the same time, you can compress the data together. Although this can reduce the space required for storage, the more data you read at the same time, the slower the read speed. If a program only needs to read a small amount of data at a time, it is best to compress these data in different user memories, so that the reader needs to send fewer commands and run faster, but the overall space used is also more many.

In a closed-loop program, you can use a special format to write data into user memory, but if you need to share data with business partners, you need to use a standard designed specifically for supply chain programs: GS1 application identifier ( For consumer supply chain), ANSI data identifier (for manufacturing), Text element identifier (for aerospace). Each standard provides many common descriptive data elements, such as shelf life, batch number, size, and weight, and also specifies the standard coding to identify each data element in user memory.