Magnetic stripe coding
Plastic card encoder with magnetic stripe
The magnetic strip allows you to automate the process of receiving discounts.
A magnetic stripe is a storage medium with a certain amount of memory, which is contained in encoded form. Magnetic stripe information is machine readable. For standard readers (readers), the strip is usually made 12.7 mm or 6.35 mm (0.5 inches) wide and is located at a distance of 4 mm from the edge of the card.
The strip can be manufactured for different magnetic field strengths. Based on this parameter, they are distinguished: LoCo (Low Coercitive) and HiCo (High Coercitive).
Plastic cards with a HiCo magnetic stripe are less susceptible to demagnetization by external magnetic fields than those with a LoCo stripe.
According to the ISO 7811 standard, the strip has three tracks:
- the first stores numeric and alphabetic data (for example, full name in bank cards;
- the second is used for numerical data (for example, for accounting in loyalty programs;
- the third carries additional numerical information (practically not used).
Recording information on a magnetic stripe
Only Latin letters can be recorded on magnetic tracks; Cyrillic letters cause an error in the operation of the recording device.1-track – alphanumeric information: up to 76 familiar places QWERTYUIOPASDFGHJKLZXCVBNM1234567890: ; = + ( ) – ' — (key “ ' E) ! @ # ^ & * < > / \ All Latin letters are CAPITAL.
The information will be surrounded by service characters:
" % " at the beginning of the line, " ? » at the end of the line
Service sign „?” is added at the end of each database line and marks the end of writing to the strip and is not displayed when read.
2-track – only numbers: 1234567890 and the “=” sign, up to 37 characters, the space is displayed on the strip with the “=” sign, the “?” means the end of recording on the magnetic stripe and is not displayed when reading.
The information will be surrounded by service symbols:
" ; " at the beginning of the line, " ? " at the end of the line.
3-track – numbers only: 1234567890 and the “=” sign, up to 104 acquaintances, the space is displayed on the tape with the “=” sign, the “?” means the end of recording on the tape and is not displayed when reading.
The information will be surrounded by service characters:
» _ « at the beginning of the line, » ? " at the end of the line.
Encoding contactless smart cards
To write or read information on smart cards, we need a card reader and software. All devices mainly operate at frequencies of 13.56 MHz, 125 kHz and 860 MHz. It is not possible to add information to all cards, for example, EM-Marine.
EM-Marine can only be read or duplicated because the card chip contains only a number and does not have built-in user memory.
Temic, Atmel T5557, despite the fact that they operate at a frequency of 125 kHz, have built-in user 330 bytes, 10 blocks of 33 bits for reprogramming, writing, reading and password protection against unauthorized writing.
Mifare operates at a frequency of 13.56 MHz, has enhanced cryptographic protection and a large number of user blocks for rewriting. Thanks to these functions, this type of card is the most popular in the world of RFID identification. Allows you to use cards as an electronic wallet, a bank card and in all other areas where strong card protection is needed.
Copying/duplicating EM-Marine charts
As can be seen from the screenshot of the EM-Marine copying program, we can copy the manufacturer code, prefix or group, card number. We also see the number presented in the Dallas Touch Memory format - Wiegand-26, this allows you to transfer the number to any existing access control system (ACS). Using the program, we can make a certain pool of numbers, for example, in order, which will allow us to enter keys into the ACS program without reading them.
Writing and encoding TEMIC cards (Atmel t5557, t5577)
Temic is used to record or copy numbers, can imitate EM Marine, HID and other RFID standards operating at 125 kHz. As we can see in the screenshot of the first two blocks, this is the 5-byte serial number of the card; it cannot be overwritten. The photo shows user blocks for reading and writing information and password protection with block 7. The cryptographic algorithms used in the cards allow them to be used in all access control systems, hotel keys, passes, etc.). Can also be personalized with full color printing, data printing, UltraCard CR80 stickers, lamination patch.
Writing/reading information on Mifare cards
Let's look at the example of encoding and recording Mifare Ultralight contactless cards. They operate at a frequency of 13.56 MHz, RF interface 14443A, 7 byte unique number, equipped with anti-collision (support for several cards in the field at the same time). From the screenshot of the program we see that the memory has 16 blocks (pages) of 4 bytes each with a total size of 512 bits. 32-bit OTP (One Time Programming) allows you to make a one-time entry that cannot be overwritten later. The remaining 12 user blocks of 48 bytes can be written to and read for 10,000 cycles. Data storage period is 5 years. The main feature is the 7 byte UID (unique number) written into the chip at the factory during the manufacturing stage. The rest of the Mifare standard cards have a similar internal memory architecture, the crypto protection system and the amount of internal memory change
Internal smart card number by bytes
The photo shows a table of the placement of the card number by memory bytes. The card number is stored in an array of 16 bytes, where the first byte “0” determines the length of the smart card number, the next number of bytes determines the card number. As we can see, the ICode card has a number 8 bytes long, Mifare 1k/4k has 4 bytes, HID card 4 bytes, EM-Marine 3 bytes.
(c) https://xn----8sbhe5avapfu.xn--p1ai/кодировка-пластиковых-карт/
