当前位置：网站首页>Stm32+mfrc522 completes IC card number reading, password modification, data reading and writing

Stm32+mfrc522 completes IC card number reading, password modification, data reading and writing

2022-07-26 09:11:00 【InfoQ】

One 、 Introduction to the environment

MCU:

STM32F103ZET6

Development software :

Keil5

Contactless read-write card module :

MFRC522

Two 、 Function is introduced

Use MFRC522 The module completes the verification of IC Card number reading 、 Card type differentiation 、IC Card sector password modification 、 Read and write sector data and other functions ; The underlying the SPI Analog timing , It can be easily transplanted to other devices , Complete project development . Now many embedded job designs often use this module , such as : Campus card design 、 Water card recharge consumption design 、 Bus card recharge consumption design, etc .

3、 ... and 、MFR522 Introduce

MF RC522 Is applied to 13.56MHz In contactless communication, one of a series of chips of high integration read-write card . yes NXP The company aims at “ Three watches ” Application launched a low voltage 、 Low cost 、 Small size

Contactless read-write card chip

, It is a better choice for the research and development of intelligent instruments and portable handheld devices .

MF RC522 Advanced modulation and demodulation concepts are used , Fully integrated in

13.56MHz

All types of passive contactless communication methods and protocols . Support ISO14443A Multi tier applications . The internal transmitter part can drive the reader / writer antenna and the antenna ISO 14443A/MIFARE Communication between card and transponder , No other circuits are needed . The receiver section provides a robust and effective demodulation and decoding circuit , Used for processing ISO14443A Compatible transponder signal . Digital part processing ISO14443A Frame and error detection （ Odd and even &CRC）. Besides , It also supports fast CRYPTO1 encryption algorithm , Used to verify MIFARE Series of products .MFRC522 Support MIFARE? Higher speed contactless communication , Two way data transmission rate is as high as 424kbit/s.

As 13.56MHz A new member of the chip family of highly integrated read-write card series ,MF RC522 And MF RC500 and MF RC530 There are many similarities , At the same time, it also has many characteristics and differences . The communication between it and the host adopts serial communication with less connection , And according to different user needs , selection SPI、I2C Or serial UART( similar RS232) One mode , It helps to reduce the number of connections , narrow PCB Plate volume , cost reduction .

Four 、IC Card Introduction

Contactless IC Card is also called RF card , from IC chip 、 Induction antenna composition , Encapsulated in a standard PVC Inside the card , The chip and antenna have no exposed parts . It is a new technology developed in the world in recent years , It successfully combines RFID technology with IC Combine card technology , It's over （ There is no power supply in the card ） And the problem of contact free , It is a great breakthrough in the field of electronic devices . The card is at a certain distance ( Usually it is 5—10cm) Near the surface of the reader , Through the transmission of radio waves to complete the data reading and writing operation .

RF reader to IC The card sends a set of electromagnetic waves with a fixed frequency , There's one in the card LC Series resonant circuit , Its frequency is the same as that of the reader , So, under electromagnetic excitation ,LC A resonant circuit produces resonance , So there's a charge in the capacitor ; At the other end of this charge , Connected to an electronic pump with one-way conduction , The charge in the capacitor is sent to another capacitor for storage , When the accumulated charge reaches 2V when , This capacitor can be used as a power supply to provide working voltage for other circuits , Transmit the data in the card or receive the data from the reader .

Non contact IC Between the card and the card reader, the radio wave is used to complete the reading and writing operation . The communication frequency between the two is 13.56MHZ. Non contact IC The card itself is a passive card , When the reader / writer reads and writes the card , The signal sent by the reader / writer consists of two parts superimposed : Part is the power signal , After the signal is received by the card , With its own L/C Generate a moment of energy to supply the chip to work . The other part is instruction and data signal , Command the chip to read the data 、 modify 、 Storage, etc , And return the signal to the reader / writer , Complete a read-write operation . The reader and writer are generally controlled by single chip microcomputer , It is composed of special intelligent module and antenna , And equipped with PC Communication interface , Print port ,I/O Mouth, etc , In order to apply to different fields .

M1 Card detailed indicators

M1 What is a card M1 chip , It refers to the abbreviation of chip produced by NXP, a subsidiary of Philips , Its full name is NXP Mifare1 series , Commonly used S50 And S70 Two models .

M1(S50) Card details ：

Chip type :PhilipsMifare1ICS50

storage capacity :8Kbit,16 Zones , Two passwords per partition ;

Working frequency :13.56?MHz;

Communication rate :106KBoud;

Reading and writing distance :2.5～10cm;

Reading and writing time :1～2ms;

working temperature :-20℃～55℃;

Erasure life :>100,000 Time ;

Save the data :>10 year ;

Dimensions :ISO Standard card 85.6x54x0.82;

Packaging materials :PVC、PET、PETG、0.13mm Copper wire ;

Mifare S50 and Mifare S70 Also known as Mifare Standard、Mifare Classic、MF1, Abide by ISO14443A Standard cards are the most widely used 、 The most influential one . and Mifare S70 Is the capacity of the S50 Of 4 times ,S50 Is the capacity of the 1K byte ,S70 The capacity of is 4K byte .

The operation sequence and operation command of the reader / writer to the card , The two are exactly the same . Mifare S50 and Mifare S70 Every card has a 4 Globally unique serial number of bytes , The retention period of the data on the card is 10 year , It can be rewritten 10 Ten thousand times , Read infinite times . In general applications , Regardless of whether the card will be read or written bad ,

Of course, except for violent hard damage . Mifare S50 and Mifare S70 There are two main differences . First, the reader / writer sends a request command to the card , The card type returned by both responses (ATQA) Different bytes .Mifare S50 Type of card (ATQA) yes 0004H,Mifare S70 Type of card (ATQA) yes 0002H. Another difference is that the capacity and memory structure of the two are different .

M1 The card is divided into 16 Sectors , Each sector consists of 4 block （0、1、2、3） form . Operating time , take 16 The sectors are divided into 64 Block , The absolute address number is 0-63.

The structure is as follows ：

The first 0 A sector is used to store the manufacturer code , Opinion fixed line , Non modifiable .

Blocks per sector 0、 block 1、 block 2 For data blocks , Can be used to store data . Data blocks can be read and written .

Blocks per sector 3 For the control block , Including the password A、 Storage control 、 password B. The specific structure is as follows ：

The password and control bits of each sector are independent , You can set your own password and access control according to your actual needs . Access control is 4 Bytes , common 32 position , Every block in a sector （ Including data and control blocks ） Access conditions are determined by password and access control , In access control, each block has a corresponding three control bits . The definition is as follows ：

Mifare 1 S50 General steps for white card reading and writing : Card search --> Download block password --> Read / write block data . The same is true for control blocks .

Access permission setting table of data block :（ According to the permissions you need , Complete the above byte 6、7、8 Just fill in ）

Control the read and write permission setting of the block :(

Contains a pair of passwords A

**、 Control authority 、 Read and write permission of password **)

7 6 5 4 3 2 1 0

byte 6 1 1 1 1 1 1 1 1

byte 7 0 0 0 0 1 1 1 1

byte 8 0 0 0 0 0 0 0 0

byte 9

The control permissions set are as follows :

0xFF 0x0F 0x00 0x00

Represents the permissions of the data block : Verify password A Or the code B Can read and write data blocks or add value keys .

Represents the permissions of the control block

(1) verification A After the password, you can write A/B password , Can't read the password .

  Can read control bytes (4 individual ), Unable to write control byte 

  Can read and write B password

(2) verification B After the code , Can read and write A/B password , Also readable control bytes , But the control byte cannot be written .

5、 ... and 、 Core code

5.1 rc522.c

#include &quot;sys.h&quot;
#include &quot;RFID_RC522.h&quot;
#include &quot;delay.h&quot;
#include &quot;string.h&quot;
#include &quot;usart.h&quot;

/*
 The functionality ： Porting interfaces --SPI Sequential read and write a byte 
 Function parameter ：data: The data to be written 
 return   return   value ： Data read 
*/
u8 RC522_SPI_ReadWriteOneByte(u8 tx_data)
{ 
 u8 rx_data=0; 
 u8 i;
 for(i=0;i<8;i++)
 {
 RC522_SCLK=0; 
 if(tx_data&0x80){RC522_OUTPUT=1;}
 else {RC522_OUTPUT=0;}
 tx_data<<=1; 
 RC522_SCLK=1;
 rx_data<<=1;
 if(RC522_INPUT)rx_data|=0x01;
 }
 return rx_data; 
}


/*
 The functionality ： initialization RC522 Of IO mouth  
*/
void RC522_IO_Init(void)
{
 RCC->APB2ENR|=1<<2; //PA Clock enable  
 RCC->APB2ENR|=1<<7; //PF Clock enable 
 
 //PA5  The clock  RC522_SCLK
 //PA6  Input  RC522_INPUT
 //PA7  Output  RC522_OUTPUT 
 GPIOA->CRL&=0x000FFFFF;
 GPIOA->CRL|=0x38300000;
 GPIOA->ODR|=0x3<<5;
 
 //RC522_RST <----->PF1-- Reset the foot 
 //RC522_SDA <----->PF0-- Film selection foot 
 GPIOF->CRL&=0xFFFFFF00;
 GPIOF->CRL|=0x00000033;
 GPIOF->ODR|=0x3<<0;
} 


/*
 Function description : Select the card and read the memory capacity of the card 
 Input parameters :serNum  Incoming card serial number 
 return   return   value : Card capacity returned successfully 
*/
u8 RC522_MFRC522_SelectTag(u8 *serNum) // Read card memory capacity 
{ 
 u8 i; 
 u8 status; 
 u8 size; 
 u8 recvBits; 
 u8 buffer[9];
 
 buffer[0]=PICC_ANTICOLL1; // Anti collision code 1 
 buffer[1]=0x70;
 buffer[6]=0x00; 
 for(i=0;i<4;i++) 
 {
 buffer[i+2]=*(serNum+i); //buffer[2]-buffer[5] Is the card serial number 
 buffer[6]^=*(serNum+i); // Card check code 
 }
 
 RC522_CalulateCRC(buffer,7,&buffer[7]); //buffer[7]-buffer[8] by RCR Check code 
 RC522_ClearBitMask(Status2Reg,0x08);
 status=RC522_PcdComMF522(PCD_TRANSCEIVE,buffer,9,buffer,&recvBits);
 
 if((status==MI_OK)&&(recvBits==0x18)) 
 size=buffer[0]; 
 else 
 size=0;
 
 return size; 
}


/*
 The time delay function , Nanosecond 
*/
void RC522_Delay(u32 ns)
{
 u32 i;
 for(i=0;i<ns;i++)
 {
 __nop();
 __nop();
 __nop();
 }
}


/*
 The functionality ：RC522 Chip initialization 
*/
void RC522_Init(void)
{
 RC522_IO_Init(); //RC522 initialization 
 RC522_PcdReset(); // Reset RC522 
 RC522_PcdAntennaOff(); // Turn off the antenna 
 DelayMs(2); // Time delay 2 millisecond 
 RC522_PcdAntennaOn(); // Turn on the antenna 
 M500PcdConfigISOType('A'); // Set up RC632 How it works 
}


/*
 The functionality ： Reset RC522
*/
void RC522_Reset(void)
{
 RC522_PcdReset(); // Reset RC522
 RC522_PcdAntennaOff(); // Turn off the antenna 
 DelayMs(2); // Time delay 2 millisecond 
 RC522_PcdAntennaOn(); // Turn on the antenna  
} 


/*
 work   can :  Card search 
 Parameter description : req_code[IN]: Card search method 
 0x52 =  All in the sensing area are consistent with 14443A Standard card 
 0x26 =  Find a card that has not entered sleep state 
 pTagType[OUT]: Card type code 
 0x4400 = Mifare_UltraLight
 0x0400 = Mifare_One(S50)
 0x0200 = Mifare_One(S70)
 0x0800 = Mifare_Pro(X)
 0x4403 = Mifare_DESFire
 return   return   value :  Successfully returns MI_OK
*/
char RC522_PcdRequest(u8 req_code,u8 *pTagType)
{
 char status; 
 u8 unLen;
 u8 ucComMF522Buf[MAXRLEN]; // MAXRLEN 18

 RC522_ClearBitMask(Status2Reg,0x08); // clear RC522 Register bit ,/ Receive data command 
 RC522_WriteRawRC(BitFramingReg,0x07); // Write RC632 register 
 RC522_SetBitMask(TxControlReg,0x03); // Set up RC522 Register bit 
 
 ucComMF522Buf[0]=req_code; // Card search method 
 
 status=RC522_PcdComMF522(PCD_TRANSCEIVE,ucComMF522Buf,1,ucComMF522Buf,&unLen); // adopt RC522 and ISO14443 Card communication 
 
 if((status==MI_OK)&&(unLen==0x10))
 { 
 *pTagType=ucComMF522Buf[0];
 *(pTagType+1)=ucComMF522Buf[1];
 }
 else
 {
 status = MI_ERR;
 } 
 return status;
}


/*
 work   can :  Collision proof 
 Parameter description : pSnr[OUT]: Card serial number ,4 byte 
 return   return :  Successfully returns MI_OK
*/
char RC522_PcdAnticoll(u8 *pSnr)
{
 char status;
 u8 i,snr_check=0;
 u8 unLen;
 u8 ucComMF522Buf[MAXRLEN]; 
 
 RC522_ClearBitMask(Status2Reg,0x08); // clear RC522 Register bit  
 RC522_WriteRawRC(BitFramingReg,0x00); // Write 
 RC522_ClearBitMask(CollReg,0x80); // clear 
 
 ucComMF522Buf[0]=PICC_ANTICOLL1; //PICC_ANTICOLL1 = 0x93
 ucComMF522Buf[1]=0x20;
 
 status=RC522_PcdComMF522(PCD_TRANSCEIVE,ucComMF522Buf,2,ucComMF522Buf,&unLen); //0x0c, adopt RC522 and ISO14443 Card communication 
 //PCD_TRANSCEIVE = Send and receive data 
 //2： The length of data bytes written to the card 
 //ucComMF522Buf: The address where the data is stored 
 //unLen： The length of data read from the card 
 if(status==MI_OK)
 {
 for(i=0;i<4;i++)
 { 
 *(pSnr+i)=ucComMF522Buf[i]; // Assign the read card number to pSnr
 snr_check^=ucComMF522Buf[i];
 }
 if(snr_check!=ucComMF522Buf[i])
 {
 status = MI_ERR;
 }
 } 
 RC522_SetBitMask(CollReg,0x80);
 return status;
}


/*
 work   can ： Select card 
 Parameter description ：pSnr[IN]: Card serial number ,4 byte 
 return   return ： Successfully returns MI_OK
*/
char RC522_PcdSelect(u8 *pSnr)
{
 char status;
 u8 i;
 u8 unLen;
 u8 ucComMF522Buf[MAXRLEN]; 
 
 ucComMF522Buf[0]=PICC_ANTICOLL1;
 ucComMF522Buf[1]=0x70;
 ucComMF522Buf[6]=0;
 
 for(i=0;i<4;i++)
 {
 ucComMF522Buf[i+2]=*(pSnr+i);
 ucComMF522Buf[6]^=*(pSnr+i);
 }
 
 RC522_CalulateCRC(ucComMF522Buf,7,&ucComMF522Buf[7]); // use MF522 Calculation CRC16 function , Check the data 
 RC522_ClearBitMask(Status2Reg,0x08); // clear RC522 Register bit 
 status=RC522_PcdComMF522(PCD_TRANSCEIVE,ucComMF522Buf,9,ucComMF522Buf,&unLen);
 if((status==MI_OK)&&(unLen==0x18))status=MI_OK;
 else status=MI_ERR;
 
 return status;
}


/*
 work   can ： Verify the card password 
 Parameter description ：auth_mode[IN]:  Password authentication mode 
 0x60 =  verification A secret key 
 0x61 =  verification B secret key  
 addr[IN]： Block address 
 pKey[IN]： Sector password 
 pSnr[IN]： Card serial number ,4 byte 
 return   return ： Successfully returns MI_OK
*/ 
char RC522_PcdAuthState(u8 auth_mode,u8 addr,u8 *pKey,u8 *pSnr)
{
 char status;
 u8 unLen;
 u8 ucComMF522Buf[MAXRLEN]; //MAXRLEN 18( Size of array )
 
 // Verification mode + Block address + Sector password + Card serial number  
 ucComMF522Buf[0]=auth_mode; 
 ucComMF522Buf[1]=addr; 
 memcpy(&ucComMF522Buf[2],pKey,6); // Copy , Copy 
 memcpy(&ucComMF522Buf[8],pSnr,4); 
 
 status=RC522_PcdComMF522(PCD_AUTHENT,ucComMF522Buf,12,ucComMF522Buf,&unLen);
 if((status!= MI_OK)||(!(RC522_ReadRawRC(Status2Reg)&0x08)))status = MI_ERR;
 return status;
}


/*
 work   can ： Read M1 A data card 
 Parameter description ： 
 addr： Block address 
 p ： Read out block data ,16 byte 
 return   return ： Successfully returns MI_OK
*/ 
char RC522_PcdRead(u8 addr,u8 *p)
{
 char status;
 u8 unLen;
 u8 i,ucComMF522Buf[MAXRLEN]; //18

 ucComMF522Buf[0]=PICC_READ;
 ucComMF522Buf[1]=addr;
 RC522_CalulateCRC(ucComMF522Buf,2,&ucComMF522Buf[2]);
 status=RC522_PcdComMF522(PCD_TRANSCEIVE,ucComMF522Buf,4,ucComMF522Buf,&unLen);// adopt RC522 and ISO14443 Card communication 
 if((status==MI_OK&&(unLen==0x90)))
 {
 for(i=0;i<16;i++)
 {
 *(p +i)=ucComMF522Buf[i];
 }
 }
 else
 { 
 status=MI_ERR;
 }
 return status;
}


/*
 work   can ： Write data to the M1 Card designation block 
 Parameter description ：addr： Block address 
 p ： Data written to the block ,16 byte 
 return   return ： Successfully returns MI_OK
*/ 
char RC522_PcdWrite(u8 addr,u8 *p)
{
 char status;
 u8 unLen;
 u8 i,ucComMF522Buf[MAXRLEN]; 
 
 ucComMF522Buf[0]=PICC_WRITE;// 0xA0 // Write a piece 
 ucComMF522Buf[1]=addr; // Block address 
 RC522_CalulateCRC(ucComMF522Buf,2,&ucComMF522Buf[2]);
 
 status=RC522_PcdComMF522(PCD_TRANSCEIVE,ucComMF522Buf,4,ucComMF522Buf,&unLen);

 if((status!= MI_OK)||(unLen != 4)||((ucComMF522Buf[0]&0x0F)!=0x0A))
 {
 status = MI_ERR;
 }
 
 if(status==MI_OK)
 {
 for(i=0;i<16;i++)// towards FIFO Write 16Byte data  
 { 
 ucComMF522Buf[i]=*(p +i); 
 }
 RC522_CalulateCRC(ucComMF522Buf,16,&ucComMF522Buf[16]);
 status = RC522_PcdComMF522(PCD_TRANSCEIVE,ucComMF522Buf,18,ucComMF522Buf,&unLen);
 if((status != MI_OK)||(unLen != 4)||((ucComMF522Buf[0]&0x0F)!=0x0A))
 { 
 status = MI_ERR; 
 }
 }
 return status;
}


/*
 work   can ： Command the card to sleep 
 return   return ： Successfully returns MI_OK
*/
char RC522_PcdHalt(void)
{
 u8 status;
 u8 unLen;
 u8 ucComMF522Buf[MAXRLEN]; //MAXRLEN==18
 status=status;
 ucComMF522Buf[0]=PICC_HALT;
 ucComMF522Buf[1]=0;
 RC522_CalulateCRC(ucComMF522Buf,2,&ucComMF522Buf[2]);
 status=RC522_PcdComMF522(PCD_TRANSCEIVE,ucComMF522Buf,4,ucComMF522Buf,&unLen);
 return MI_OK;
}


/*
 work   can ： use MF522 Calculation CRC16 function 
 ginseng   Count ：
 *pIn ： To read CRC The data of 
 len：- Data length 
 *pOut： Calculated CRC result 
*/
void RC522_CalulateCRC(u8 *pIn ,u8 len,u8 *pOut )
{
 u8 i,n;
 RC522_ClearBitMask(DivIrqReg,0x04); //CRCIrq = 0 
 RC522_WriteRawRC(CommandReg,PCD_IDLE);
 RC522_SetBitMask(FIFOLevelReg,0x80); // clear FIFO The pointer 
 
 // towards FIFO Middle write data  
 for(i=0;i<len;i++)
 { 
 RC522_WriteRawRC(FIFODataReg,*(pIn +i)); // Start RCR Calculation 
 }
 
 RC522_WriteRawRC(CommandReg,PCD_CALCCRC); // wait for CRC The calculation is complete  
 i=0xFF;
 do 
 {
 n=RC522_ReadRawRC(DivIrqReg);
 i--;
 }
 while((i!=0)&&!(n&0x04));//CRCIrq = 1
 
 // Read CRC The result of the calculation is  
 pOut[0]=RC522_ReadRawRC(CRCResultRegL);
 pOut[1]=RC522_ReadRawRC(CRCResultRegM);
}


/*
 work   can ： Reset RC522
 return   return ： Successfully returns MI_OK
*/
char RC522_PcdReset(void)
{
 RC522_RST=1; //PF1 Write 1
 RC522_Delay(10);
 RC522_RST=0; //PF1 clear 0
 RC522_Delay(10);
 RC522_RST=1; //PF1 Write 1
 RC522_Delay(10);
 RC522_WriteRawRC(CommandReg,PCD_RESETPHASE); // Write RC632 register , Reset 
 RC522_WriteRawRC(CommandReg,PCD_RESETPHASE); // Write RC632 register , Reset 
 RC522_Delay(10);
 
 RC522_WriteRawRC(ModeReg,0x3D); // and Mifare Card communication ,CRC Initial value 0x6363
 RC522_WriteRawRC(TReloadRegL,30); // Write RC632 register  
 RC522_WriteRawRC(TReloadRegH,0);
 RC522_WriteRawRC(TModeReg,0x8D);
 RC522_WriteRawRC(TPrescalerReg,0x3E);
 
 RC522_WriteRawRC(TxAutoReg,0x40);// It has to be 
 return MI_OK;
}


/*
 The functionality ： Set up RC632 How it works  
*/
char M500PcdConfigISOType(u8 type)
{
 if(type=='A') //ISO14443_A
 { 
 RC522_ClearBitMask(Status2Reg,0x08); // clear RC522 Register bit 
 RC522_WriteRawRC(ModeReg,0x3D); //3F//CRC Initial value 0x6363
 RC522_WriteRawRC(RxSelReg,0x86); //84
 RC522_WriteRawRC(RFCfgReg,0x7F); //4F // Adjust the sensing distance of the card //RxGain = 48dB Adjust the card sensing distance  
 RC522_WriteRawRC(TReloadRegL,30); //tmoLength);// TReloadVal = 'h6a =tmoLength(dec) 
 RC522_WriteRawRC(TReloadRegH,0);
 RC522_WriteRawRC(TModeReg,0x8D);
 RC522_WriteRawRC(TPrescalerReg,0x3E);
 RC522_Delay(1000);
 RC522_PcdAntennaOn(); // Turn on the antenna  
 }
 else return 1; // Failure , return 1
 return MI_OK; // Successfully returns 0
}


/*
 work   can ： read RC632 register 
 Parameter description ：Address[IN]: Register address 
 return   return ： Read out value 
*/
u8 RC522_ReadRawRC(u8 Address)
{
 u8 ucAddr;
 u8 ucResult=0; 
 RC522_CS=0; // Film selection RC522
 ucAddr=((Address<<1)&0x7E)|0x80;
 RC522_SPI_ReadWriteOneByte(ucAddr); // dispatch orders 
 ucResult=RC522_SPI_ReadWriteOneByte(0); // Read RC522 Returned data 
 RC522_CS=1; // Release the selection line (PF0)
 return ucResult; // Returns the data read 
}


/*
 work   can ： Write RC632 register 
 Parameter description ：Address[IN]: Register address 
 value[IN] : Value written 
*/
void RC522_WriteRawRC(u8 Address,u8 value)
{ 
 u8 ucAddr;
 RC522_CS=0; //PF0 Write  0 (SDA)(SPI1 Film selection line , Low level active )
 ucAddr=((Address<<1)&0x7E); 
 RC522_SPI_ReadWriteOneByte(ucAddr); //SPI1 Send a byte 
 RC522_SPI_ReadWriteOneByte(value); //SPI1 Send a byte 
 RC522_CS=1; //PF1 Write 1(SDA)(SPI1 Film selection line )
}


/*
 work   can ： Set up RC522 Register bit 
 Parameter description ：reg[IN]: Register address 
 mask[IN]: Set value 
*/
void RC522_SetBitMask(u8 reg,u8 mask) 
{
 char tmp=0x0;
 tmp=RC522_ReadRawRC(reg); // read RC632 register 
 RC522_WriteRawRC(reg,tmp|mask); // Write RC632 register 
}


/*
 work   can ： clear RC522 Register bit 
 Parameter description ：reg[IN]: Register address 
 mask[IN]: Clearance value 
*/
void RC522_ClearBitMask(u8 reg,u8 mask) 
{
 char tmp=0x0;
 tmp=RC522_ReadRawRC(reg); // read RC632 register 
 RC522_WriteRawRC(reg,tmp&~mask); // clear bit mask
} 


/*
 work   can ： adopt RC522 and ISO14443 Card communication 
 Parameter description ：Command[IN]:RC522 Command word 
 pIn [IN]: adopt RC522 Data sent to the card 
 InLenByte[IN]: The byte length of the transmitted data 
 pOut [OUT]: The received card returns data 
 *pOutLenBit[OUT]: Returns the bit length of the data 
*/
char RC522_PcdComMF522(u8 Command,u8 *pIn,u8 InLenByte,u8 *pOut,u8 *pOutLenBit)
{
 char status=MI_ERR;
 u8 irqEn=0x00;
 u8 waitFor=0x00;
 u8 lastBits;
 u8 n;
 u16 i;
 
 switch(Command)
 {
 case PCD_AUTHENT: // Verify key 
 irqEn=0x12;
 waitFor=0x10;
 break;
 case PCD_TRANSCEIVE: // Send and receive data 
 irqEn=0x77;
 waitFor=0x30;
 break;
 default:
 break;
 }
 RC522_WriteRawRC(ComIEnReg,irqEn|0x80); 
 RC522_ClearBitMask(ComIrqReg,0x80); // Clear all middle breaks 
 RC522_WriteRawRC(CommandReg,PCD_IDLE); 
 RC522_SetBitMask(FIFOLevelReg,0x80); // clear FIFO cache 
 
 for(i=0;i<InLenByte;i++)
 { 
 RC522_WriteRawRC(FIFODataReg,pIn[i]);
 }
 
 RC522_WriteRawRC(CommandReg,Command); 
 if(Command==PCD_TRANSCEIVE)
 { 
 RC522_SetBitMask(BitFramingReg,0x80); // Start transmission 
 }
 
 // There is a problem , The following loop 
 //i = 600;// Adjust according to the clock frequency , operation M1 Maximum waiting time for card 25ms
 i=2000;
 do 
 {
 n=RC522_ReadRawRC(ComIrqReg);
 i--;
 }
 while((i!=0)&&!(n&0x01)&&!(n&waitFor));
 
 RC522_ClearBitMask(BitFramingReg,0x80);
 if(i!=0)
 { 
 if(!(RC522_ReadRawRC(ErrorReg)&0x1B))
 {
 status=MI_OK;
 if(n&irqEn&0x01)
 {
 status=MI_NOTAGERR;
 }
 if(Command==PCD_TRANSCEIVE)
 {
 n=RC522_ReadRawRC(FIFOLevelReg);
 lastBits=RC522_ReadRawRC(ControlReg)&0x07;
 if(lastBits)
 {
 *pOutLenBit=(n-1)*8+lastBits;
 }
 else
 { 
 *pOutLenBit=n*8; 
 }
 
 if(n==0)n=1;
 if(n>MAXRLEN)n=MAXRLEN;
 for(i=0; i<n; i++)
 { 
 pOut[i]=RC522_ReadRawRC(FIFODataReg); 
 }
 }
 }
 else
 { 
 status=MI_ERR; 
 }
 }
 RC522_SetBitMask(ControlReg,0x80);// stop timer now
 RC522_WriteRawRC(CommandReg,PCD_IDLE); 
 return status;
}


/*
 The functionality ： Turn on the antenna  
 ginseng   Count ： There should be at least... Between each start-up or shutdown of natural danger launch 1ms The interval of 
*/
void RC522_PcdAntennaOn(void)
{
 u8 i;
 i=RC522_ReadRawRC(TxControlReg);
 if(!(i&0x03))
 {
 RC522_SetBitMask(TxControlReg,0x03);
 }
}


/*
 The functionality ： Turn off the antenna  
 ginseng   Count ： There should be at least... Between each start-up or shutdown of natural danger launch 1ms The interval of 
*/
void RC522_PcdAntennaOff(void)
{
 RC522_ClearBitMask(TxControlReg,0x03); // clear RC522 Register bit 
}

5.2 rc522.h

#ifndef RFID_RC522_H
#define RFID_RC522_H
#include &quot;sys.h&quot;

/*
RC522 External interface of RF module : 
*1--SDA <----->PF0-- Film selection foot 
*2--SCK <----->PA5-- Clock line 
*3--MOSI<----->PA7-- Output 
*4--MISO<----->PA6-- Input 
*5-- In the air 
*6--GND <----->GND
*7--RST <----->PF1-- Reset the foot 
*8--VCC <----->VCC
*/
#define RC522_OUTPUT PAout(7)
#define RC522_INPUT PAin(6)
#define RC522_SCLK PAout(5)
#define RC522_CS PFout(0)
#define RC522_RST PFout(1)


//MF522 Command word 
#define PCD_IDLE 0x00 // Cancel the current command 
#define PCD_AUTHENT 0x0E // Verify key 
#define PCD_RECEIVE 0x08 // receive data 
#define PCD_TRANSMIT 0x04 // send data 
#define PCD_TRANSCEIVE 0x0C // Send and receive data 
#define PCD_RESETPHASE 0x0F // Reset 
#define PCD_CALCCRC 0x03 //CRC Calculation 


//Mifare_One Card command word 
#define PICC_REQIDL 0x26 // The antenna searching area is not in sleep state , Returns the type of card 
#define PICC_REQALL 0x52 // All cards in the antenna searching area , Returns the type of card 
#define PICC_ANTICOLL1 0x93 // Collision proof 
#define PICC_ANTICOLL2 0x95 // Collision proof 
#define PICC_AUTHENT1A 0x60 // verification A secret key 
#define PICC_AUTHENT1B 0x61 // verification B secret key   Command authentication code 
#define PICC_READ 0x30 // Reading block 
#define PICC_WRITE 0xA0 // Write a piece 
#define PICC_DECREMENT 0xC0 // Deduction 
#define PICC_INCREMENT 0xC1 // Recharge 
#define PICC_RESTORE 0xC2 // Block data to buffer 
#define PICC_TRANSFER 0xB0 // Save data in buffer 
#define PICC_HALT 0x50 // Sleep 

//MF522 FIFO Length definition 
#define DEF_FIFO_LENGTH 64 //FIFO size=64byte
#define MAXRLEN 18


//MF522 Register definition 
// PAGE 0
#define RFU00 0x00 
#define CommandReg 0x01 
#define ComIEnReg 0x02 
#define DivlEnReg 0x03 
#define ComIrqReg 0x04 
#define DivIrqReg 0x05
#define ErrorReg 0x06 
#define Status1Reg 0x07 
#define Status2Reg 0x08 
#define FIFODataReg 0x09
#define FIFOLevelReg 0x0A
#define WaterLevelReg 0x0B
#define ControlReg 0x0C
#define BitFramingReg 0x0D
#define CollReg 0x0E
#define RFU0F 0x0F
// PAGE 1 
#define RFU10 0x10
#define ModeReg 0x11
#define TxModeReg 0x12
#define RxModeReg 0x13
#define TxControlReg 0x14
#define TxAutoReg 0x15
#define TxSelReg 0x16
#define RxSelReg 0x17
#define RxThresholdReg 0x18
#define DemodReg 0x19
#define RFU1A 0x1A
#define RFU1B 0x1B
#define MifareReg 0x1C
#define RFU1D 0x1D
#define RFU1E 0x1E
#define SerialSpeedReg 0x1F
// PAGE 2 
#define RFU20 0x20 
#define CRCResultRegM 0x21
#define CRCResultRegL 0x22
#define RFU23 0x23
#define ModWidthReg 0x24
#define RFU25 0x25
#define RFCfgReg 0x26
#define GsNReg 0x27
#define CWGsCfgReg 0x28
#define ModGsCfgReg 0x29
#define TModeReg 0x2A
#define TPrescalerReg 0x2B
#define TReloadRegH 0x2C
#define TReloadRegL 0x2D
#define TCounterValueRegH 0x2E
#define TCounterValueRegL 0x2F

// PAGE 3 
#define RFU30 0x30
#define TestSel1Reg 0x31
#define TestSel2Reg 0x32
#define TestPinEnReg 0x33
#define TestPinValueReg 0x34
#define TestBusReg 0x35
#define AutoTestReg 0x36
#define VersionReg 0x37
#define AnalogTestReg 0x38
#define TestDAC1Reg 0x39 
#define TestDAC2Reg 0x3A 
#define TestADCReg 0x3B 
#define RFU3C 0x3C 
#define RFU3D 0x3D 
#define RFU3E 0x3E 
#define RFU3F 0x3F


// and MF522 Error code returned during communication 
#define MI_OK 0
#define MI_NOTAGERR 1
#define MI_ERR 2

#define SHAQU1 0X01
#define KUAI4 0X04
#define KUAI7 0X07
#define REGCARD 0xa1
#define CONSUME 0xa2
#define READCARD 0xa3
#define ADDMONEY 0xa4

/*
 RC522 Various driving functions 
*/
u8 RC522_SPI_ReadWriteOneByte(u8 tx_data);
void RC522_IO_Init(void);
u8 RC522_MFRC522_SelectTag(u8 *serNum);
void RC522_Delay(u32 ns);
void RC522_Init(void);
void RC522_Reset(void);
char RC522_PcdRequest(u8 req_code,u8 *pTagType);
char RC522_PcdAnticoll(u8 *pSnr);
char RC522_PcdSelect(u8 *pSnr);
char RC522_PcdAuthState(u8 auth_mode,u8 addr,u8 *pKey,u8 *pSnr);
char RC522_PcdRead(u8 addr,u8 *p);
char RC522_PcdWrite(u8 addr,u8 *p);
char RC522_PcdHalt(void);
void RC522_CalulateCRC(u8 *pIn ,u8 len,u8 *pOut );
char RC522_PcdReset(void);
char M500PcdConfigISOType(u8 type);
char M500PcdConfigISOType(u8 type);
u8 RC522_ReadRawRC(u8 Address);
void RC522_WriteRawRC(u8 Address,u8 value);
void RC522_SetBitMask(u8 reg,u8 mask) ;
void RC522_ClearBitMask(u8 reg,u8 mask);
char RC522_PcdComMF522(u8 Command,u8 *pIn,u8 InLenByte,u8 *pOut,u8 *pOutLenBit);
void RC522_PcdAntennaOn(void);
void RC522_PcdAntennaOff(void);
#endif