GetUSB.info just posted a nice article on how to read the PSN from an SD card, or product serial number. Some also call this reading the CID number from an SD card. The CID number is a unique identifier number or serial number created on the SD or microSD media at the time of manufacturing. This is a number which cannot be changed or manipulated by the host computer.
The CID number is most often used for vendors or manufacturers to lock in software to a specific device. Since the CID number cannot be changed or modified, it’s a great way to prevent unauthorized distribution or content or software.
Some manufacturers require to read the CID number from SD media before the software is published and this is what GetUSB.info talks about. For a full description of the article, make the jump: How to read CID number from SD media.
Here is a snap shot of the CID reading tool for 20 SD devices:
