Tag RFID MIFARE is currently one of the most commonly used RFID tags. MIFARE is a series of RF cards complying with ISO14443A standard produced by NXP. ويشمل MIFARES50, MIFARE S70, الطائرة MIFARE, MIFARE برو, ميفاريديسفيري, إلخ. Due to the huge influence of MIFARE, the industry sometimes produces RF cards that comply with ISO14443A standards. Also known as “MIFARE”, especially the MIFARES50 card, هو تقريبا المتحدث باسم ISO14443A القياسية.
As for the origin of the name “MIFARE”, ويقال انه في 1998 Philips acquired the Swiss company Mikron, which previously developed a charging system called MIkron FARE-collectionSystem, نظام الشحن Mikron, abbreviated as MIFARE.
MIFARE series cards sometimes refer to MIFARE UltraLight as MF0, MIFARES50 and S70 as MF1, مفتاح برو كما MF2, and MIFARE Desfire as MF3 depending on the chip used in the card.
The common feature of the MIFARE series is to comply with the ISO14443A international standard. The common features of the Tag RFID MIFARE are as follows:
1. انهم جميعا علي مقربه من البطاقة PICC (القرب ICC), read and write distances up to 10cm.
2. The RF frequency of the Tag RFID MIFARE is 13.56MHz ± 7KHz.
3. Tag RFID MIFAREs are passive and contactless, and energy is provided by the RF field generated by the reader.
4. The magnetic field strength of the RF field generated by the reader is between 1.5A/m and 7.5A/m. The Tag RFID MIFARE can work continuously in this field strength interval.
5. The Tag RFID MIFARE first enters the reader’s RF field to complete the initialization, ثم ينتظر الأمر القارئ. The data exchange between the reader and the card always adopts the RTF mode, إنه, the reader first issues a command, والبطاقة تستجيب للأمر في غضون فتره زمنيه محدده. If the reader does not have a command, لا يمكن للبطاقة التحدث أولا علي اي حال.
6. The reader sends a command to the Tag RFID MIFARE using a modified Miller code of 100% طلب التحوير, and the Tag RFID MIFARE uses a subcarrier modulated Manchester code.
7. The data rate between the card and the reader is 4 انواع: 106كيلو بايت, 212كيلو بايت, 424كيلو بايت, 847كيلو بايت. ومع ذلك, قبل قراءه الأمر اختيار بطاقة (شامله), يمكن ان يكون معدل الاتصالات فقط 106 كيلوبت في الثانية. After reading the card selection, the Tag RFID MIFARE and reader can negotiate which rate to use. How does 106Kbps come from? It is obtained by dividing the carrier frequency by 13.56MHz and dividing by 128. The popular saying is “carrier 128 frequency division”.
8. When the Tag RFID MIFARE does not enter the RF field, it is called the Power-Off state. بعد دخول حقل RF, it enters the Idle state after receiving the power reset. بعد تلقي أمر المكالمة من القارئ, it enters the Ready state. بعد تحديد الدورة المضادة للتصادم, it enters the active state, and enters the sleep state after receiving the sleep command or the unfamiliar command in the active state.
9. Tag RFID MIFAREs have a globally unique serial number, والتي قد تكون 4 وحدات البايت, 7 بايت أو 10 وحدات البايت. When multiple Tag RFID MIFAREs enter the RF field of the reader at the same time, the cards follow the bit-oriented anti-collision mechanism, and the card reader selects a unique Tag RFID MIFARE to operate. After the reader has finished operating a Tag RFID MIFARE, it can send a sleep command to put the card to sleep, and the reader continues to operate on other Tag RFID MIFAREs.
10. These Tag RFID MIFAREs have the same operation steps before the card selection (بما في ذلك). The operation after the Tag RFID MIFARE selection is different. على سبيل المثال, بعض الحاجة إلى التحقق من كلمه المرور, بعض لا تحتاج اليها, and the way to verify the password. وهناك أيضا اختلافات.
11. It takes two steps to enter the magnetic field from the Tag RFID MIFARE to the Tag RFID MIFARE.
The first step is for the reader to call the Tag RFID MIFARE in the magnetic field, and the Tag RFID MIFARE responds to the call.
(1) Since there may be a card in the magnetic field that has just entered the magnetic field and is electrically reset, it may also have a Tag RFID MIFARE that has been operated by the reader and sent to the sleep state by the reader. Different types of Tag RFID MIFAREs, the reader uses two different commands to make calls: طلب بطاقة (رقابه, 0x26) وبطاقة الايقاظ (الاستيقاظ, 0x52).
(2) The Tag RFID MIFARE Request (رقابه) يمكن فقط استدعاء بطاقات في حاله الخمول, and WAKE-UP can call all cards, بما في ذلك بطاقات في الدول وقف وعارضه.
(3) After receiving the card call command, the Tag RFID MIFARE will respond to the command (الاجابه علي طلب, ATQA), telling the reader whether to comply with the bit-oriented anti-collision mechanism. ان لم يكن, the reader will not naturally Will operate down, unless the two parties have agreed on a special anti-collision agreement, but it is not called “obey ISO14443A”. ATQA has two bytes. لم يتم تحديد قيمه البايت الأول (RFU). The upper two bits of the second byte b7b6 indicate the length of the card serial number (“00” هو 4 وحدات البايت, و “01” هو 7 الكلمات. قسم, “10” هو 10 وحدات البايت), لم يتم تحديد قيمه البت b5 (RFU), b4-b0 indicates whether or not the bit-oriented anti-collision mechanism is observed. إذا لوحظ, يجب ان يكون b4-b0 واحد وفقط 1 بت هو 1. وعادة ما, the ATQA of MIFARES50 is 0004H, و ATQA من S70 هو 0002H, the ATQA of MIFAREUltraLight is 0044H, و ATQA من الضوء المفتاح هو 0010H, and the ATQA of MIFAREDesfire is 0434H. من المالوف في هذه الصناعة للاتصال ATQA نوع البطاقة, and it is called “MIFARE S50 card type is 0004H, MIFARES70 نوع البطاقة هو 0002H, MIFARE UltraLight card type is 0044H, نوع بطاقة المفتاح هو 0344H…”, this statement is actually not Rigorous. Cards with ATQA 0044H and 0344H have appeared, ولكن هذه البطاقة ليست ميفاريولتراليت و ميديس ديفاير, but a new 7-byte MIFARES50. هذا أمر طبيعي, because ISO 14443A stipulates that the role of ATQA is to indicate whether the card complies with the bit-oriented anti-collision mechanism and the length of its own card serial number, and does not indicate which type of card.
(1) The reason why “المضادة للاصطدام” و “selection” are put together is because the command codes of the two are the same, the difference is how many confirmed card serial numbers are included after the command code.
(2) Bit-oriented anti-collision mechanism Each anti-collision cycle requires a 32-bit card number to participate. The reader sends an anti-collision command code to all cards participating in the anti-collision, and tells the card how many card serial numbers have been determined, so that the front part of the card serial number is the same as the confirmed serial number issued by the reader. اجراء استجابه.
(3) If the confirmed card serial number is less than 32 معاهدات الاستثمار الثنائية, which is an anti-collision command, the card will return the remaining card serial number part except the confirmed card serial number; if the confirmed card serial number is equal to 32 معاهدات الاستثمار الثنائية, The card selection command will cause the selected card to respond to the selection (SelectAcKnowledge, SAK).
(4) Another difference between the anti-collision and card selection commands is that the card selection command has a CRC_A check, and the anti-collision command has no CRC_A check.
(5) If the card number is 4 وحدات البايت, the command code for anti-collision selection is 0x93.
(6) If the card number is 7 وحدات البايت, then two levels (cascadelevel) anti-collision selection is required. The command code of the first level (مستوى تتالي 1) is 0x93; the first 3 bytes of the card number participate; The command code of the second level (مستوى تتالي 2) is 0x95, and the last 4 bytes of the card number participate.
(7) If the card number is 10 وحدات البايت, then three levels (مستوى تتالي) anti-collision selection is required. The command code of the first level (مستوى تتالي 1) is 0x93, and the first 3 bytes of the card number participate; The command code of the second level (مستوى تتالي 2) is 0x95, and the 4th, 5th, and 6th bytes of the card number participate; the command code of the third level (cascade level3) is 0x97, and the last 4 bytes of the card number participate.
(8) You may have discovered that it is said that each anti-collision cycle requires a 32-bit card number to participate. لاحقا, it can be said that it can participate in 3 وحدات البايت (24بت). Is it inconsistent? نعم, in order to make up 32bit, if only 3 bytes of card number participate in the anti-collision loop, the card automatically adds a byte 0x88 before the 3 card number bytes. This 0x88 is called a cascade tag, which satisfies Anti-collision cycle requirements for 32bit card numbers.
(9) Anti-collision selection loop for each layer. If the card is selected, the card should return to SelectAcKnowledge (SAK) to tell the reader whether it needs the next level of anti-collision selection loop and whether to comply with ISO14443-4. . 12. وأخيراً, the above is the meaning of “common compliance with ISO14443A”, إنه, from the card into the magnetic field to the card is selected, their operation process is the same. وبعد ذلك, everyone parted ways, and some continued to abide by ISO14443-4, some began to verify the password, and some can directly read and write operations. To get Tag RFID MIFARE: https://www.rfidhy.com/contact-us/