Shulou(Shulou.com)06/01 Report--

This article shows you the technical details and working principle of Mifare 1k card. The content is concise and easy to understand. It will definitely brighten your eyes. I hope you can get something through the detailed introduction of this article.

Ready to start work, record some basic information found, dragged on for a long time, finally about to start, hey.

I. main indicators

Capacity is 8K bit EEPROM

Divided into 16 sectors, each sector is 4 blocks, each block is 16 bytes, with block as access unit

Each sector has an independent set of passwords and access control

Each card has a unique serial number, which is 32 bits

Has anti-collision mechanism and supports multi-card operation.

No power supply, built-in antenna, including encryption control logic and communication logic circuit

The retention period of the data is 10 years, and it can be rewritten 100,000 times and read indefinitely.

Working temperature:-20 ℃ ~ 50 ℃ (temperature is 90%), M1 card is packaged with PET material, and the temperature can reach 100 ℃.

Working frequency: 13.56MHZ

Communication speed: 106KBPS

Read-write distance: within 10cm (related to reader)

Second, storage structure

The M1 card is divided into 16 sectors, each of which consists of 4 blocks (Block 0, Block 1, Block 2, Block 3). (we also number the 64 blocks of the 16 sectors as 0room63 according to the absolute address, and the storage structure is shown in the following figure:

Block 0 of sector 0 (that is, absolute address block 0), which is used to store vendor code, has been solidified and cannot be changed.

Block 0, block 1 and block 2 of each sector are data blocks that can be used to store data. Data blocks can be used in two ways:

Used for general data preservation, you can read and write operations.

As a data value, you can initialize values, add values, decrease values, and read values.

Block 3 of each sector is a control block, including password A, access control, and password B. The specific structure is as follows:

The password and access control of each sector are independent, and the password and access control can be set according to the actual needs. The access control is 4 bytes, a total of 32 bits. The access conditions of each block (including data block and control block) in the sector are determined by the password and access control. Each block in the access control has three corresponding control bits, which are defined as follows:

The three control bits exist in the access control byte in both positive and negative forms, which determines the access rights of the block (for example, KEY A must be verified for impairment operations, KEY B must be verified for added value operations, etc.). The position of three control bits in the access control byte, taking block 0 as an example:

The structure of the access control (4 bytes, where byte 9 is used) is as follows:

The access controls for data blocks (Block 0, Block 1, Block 2) are as follows:

For example, when the access control bit C10C20 C30room100 of block 0, it indicates that

Can be read after verifying that password An or password B is correct

Can be written after verifying that password B is correct

Cannot add or decrease value.

The access control of control block 3 is different from that of data blocks (blocks 0, 1, 2). Its access control is as follows:

For example, when the access control bit C13 C23 C33 of block 3 is 100, it means:

Password A: unreadable, write (change) after verifying that KEYA or KEYB is correct.

Access control: after verifying that KEYA or KEYB is correct, it is readable and writable.

Password B: after verifying that KEYA or KEYB is correct, it is readable and writable.

The above contents are the technical details of Mifare 1k card and how it works. Have you learned the knowledge or skills? If you want to learn more skills or enrich your knowledge reserve, you are welcome to follow the industry information channel.

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