如何使用PN532读取无源NFC/RFID单元?
我从eBay上拿到了一个带有白色卡片和蓝色遥控钥匙转发器的小红色“ELECHOUSE V3”套件,并且我编写了一个C程序,它可以创建和解码数据包,并且可以发送命令并使用AC数据包,我可以读取版本和状态。我没有使用任何RFID库,我只是使用普通的C语言编写自己的简单库,因为我想了解它,我想为真正想了解它的人发布一个简单的单个文件演示,而不是仅仅使用一些arduino lib或其他。这就是我没有问的所有问题。如何使用PN532读取无源NFC/RFID单元?
因此,这里是我提出质疑:
什么是确切的指令发送给扫描无源(无动力)转发器的存在?我不确定它们是什么类型的,但是它们随套件一起提供,可能是ISO 14443/14443A。
其实,我尝试了我的三星Galaxy S4上的标签,它说它们是ISO 14443-3A恩智浦MIFARE Classic 1K - 不支持。但它仍然显示他们的序列号。
扫描所有支持的卡类型的确切命令是什么?发送命令我使用我的功能,如下所示: sendcmd(“0x4A 0x01 0x00”); (0xD4的TFI自动添加到命令中,并且前导码/ len/lcs /校验和全部被计算并处理。)
我确实收到了我的命令的ACK,但无法弄清楚哪个发送扫描卡片或读取它们的命令。
如果我可以让PN532向我吐出卡片扫描数据,我应该可以使用PN532数据表来解析它。
非常感谢你,
杰西
啊行..想这似乎在没有成功的数据表的相关指示一切后,我转身业余无线电到13.56MHz的CW/LSB和有没有什么可以听到的。所以只是为了踢我尝试了RFRegulationTest命令,并解锁了整个事情!似乎是一个测试命令,打开发射机并保持打开状态,直到发出另一个命令为止......但它会根据需要初始化某些东西!
所以这里需要做的卡NXP NP532扫描命令: (我使用RS232在115200,但应该是其他接口类似。)
你发送给它:
0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0x00 0xFF 0x03 0xFD 0xD4 0x58 0x00 0xD4
,你会得到一个ACK和发射器将在键: 为0x00为0x00 0xFF的为0x00 0xFF的0×00
而在这一点上,发射器将键上。也许让它做超过100ms或东西,那么你就可以查询卡开始扫描:
0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0x00 0xFF 0x04 0xFC 0xD4 0x4A 0x02 0x00 0xE0
的芯片,然后将打开无线电发射器,并开始扫描卡,直到卡进来的,那么它读取序列号,关闭发射机,并给你一个包,其中包含:
0x4B,0x01/0x02(取决于是否检测到1或2张卡),其次是有关卡的各种信息,如它的序列号。
您还可以设置尝试的最大数量给出的0x4A 0×02 0×00命令时,通过尝试次数设定为小于0xFF的一个数字,这样它会尝试:
sendcmd("0x32 0x05 0xFF 0x01 0x10")
在这种情况下,当你给读命令(0x4A 0×02×00),它会尝试第二(0×10次)的一小部分,然后放弃,并发送包含包:
0x4B, 0x00
这意味着“牌发现:零。 “
有关详细信息,请参阅数据表,它告诉您需要了解的所有信息,除非我运行射频测试命令之前,无法知道如何启用发射器。
无论如何,如果你喜欢,只要持续发送第二个命令几次或更慢,并且每次发送该命令时,它都会扫描并让你知道是否有范围内的卡!
或者,如果您将重试次数设置为0xFF,则它会一直尝试,直到它检测到一张卡,然后您只需在发现卡时重新发送scan-for-card命令。
0xFF的长字符串只是为了唤醒设备,因为它进入睡眠状态,并且会丢失发送的前几个字节。
我给出的以一串0xFF开头的例子是整个完整的数据包,包括前导码,长度字段,校验和和计算的所有数据。您可以直接发送它们来扫描卡片。
初始RF测试命令和重试设置命令只需要在上电时运行一次,之后只需根据需要重新发送读取命令。
我PN532芯片报告本身作为版本:1.6
这里是我的小样本程序:
(我从SO后解禁的RS232初始化部分 - 感谢谁写的!)
(它适用于Linux。编译gcc nfc.c -o nfc.e)
(应该能够将它移植到任何平台上,你只需要处理串口 - 其余与平台无关)
(也请注意,这仅仅是扫描卡片并返回序列号/ NFCID,并且仅适用于Mifare,ISO/IEC14443-3 A型卡在106kbps的被动模式下。如果你想实际读/写卡上的内存,你必须编写更多的代码,但这至少说明了开始以及命令结构的工作方式,并提供了一些方便的例程来发送和解码数据包。)
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
int debug=0;
int fd;
void init_rs232(void);
void sendpacket(unsigned char * payload, int len);
void sendcmd(char * payload);
int main(void)
{
printf("Welcome!\n");
init_rs232();
int waitfor;
#define PACKET 1
#define ACK 2
sendcmd("0x58 0x00");waitfor=ACK; //RFRegulationTest -- This command is used for radio regulation test.
int cstate=0; //Chat state, config state, whatever..
int lc=0;
while(1)
{
lc++; //Send a scan command every second or so.
if(lc>1000)
{
lc=0;
sendcmd("0x4A 0x02 0x00"); //InListPassiveTarget -- The goal of this command is to detect as many targets (maximum MaxTg) as possible (max two) in passive mode.
}
if(cstate==1) //ACK's set the bottom bit in state, allowing it to go onto the next state.
{
sendcmd("0x02");waitfor=PACKET; //Read the version out of the PN532 chip.
cstate++;
}
if(cstate==3) //ACK's set the bottom bit in state, allowing it to go onto the next state.
{
sendcmd("0x04");waitfor=PACKET; //Get current status.
cstate++;
}
if(cstate==5)
{
waitfor=PACKET;
sendcmd("0x32 0x05 0xFF 0x01 0x10");//Max retries - last byte is for passive: 0=1 try, 1=2 tries, 254=255 tries, 0xFF=infinite retries.
//If last byte is 0xFF, then unit starts scanning for cards indefinitely. As soon as it detects a card, it stops scanning and returns info.
//If last byte is less than 0xFF, it tries scans and as soon as it finds a card returns info on it and stops trying, but
//if it never finds a card in the specified number of retries, it gives up and returns 0x4B, 0x00 (Cards found: Zero.)
cstate++;
}
//Alternative way to send a new scan command each time the previous one gives up or finds a card:
// if(cstate==7)
// {
// waitfor=PACKET;
// sendcmd("0x4A 0x02 0x00"); //InListPassiveTarget
// cstate--;
// }
static unsigned char buffin [1000024];
static unsigned char buf[1],bufo[1];
int n;
static int bi=0;
unsigned char len,lcs,tfi,dcs;
bufo[0]=buf[0];
n=read(fd,buf,sizeof(buf));
if(n!=0)
{
if(n>0)
{
if(bi<1000000)
{
static int state=0;
if(state==0) //Waiting for preamble..
{
if((bufo[0]==0)&&(buf[0]==0xFF)){state=10;}
}
else if(state==10) //Waiting for Len
{
len=buf[0];
state=20;
}
else if(state==20) //Waiting for len checksum
{
if((len==0xFF)&&(buf[0]==0xFF)){printf("ERROR: BIG PACKET. Bye.\n");exit(-2);}
if((len==0x00)&&(buf[0]==0xFF)){state=21;}
else if((len==0xFF)&&(buf[0]==0x00)){state=21;}
else
{
lcs=buf[0]+len;
if(lcs){printf("ERROR: len checksum failed! 0x%02X\n",buf[0]);}
state=30;
}
}
else if(state==21) //Waiting for the 0x00 after ack/nack..
{
state=0;
if(buf[0]==0x00)
{
if(bufo[0]==0xFF)
{
if(debug){printf("ACK!\n");}
if(waitfor==ACK){cstate=cstate|1;}
}
if(bufo[0]==0x00){printf("NACK!\n");}
}else{
printf("ERROR: Invalid length, or ack/nack missing postamble...\n");
}
}
else if(state==30) //Waiting for tfi..
{
tfi=buf[0];
//printf("tfi=0x%02X\n",tfi);
dcs=tfi;
bi=0;
state=40;
}
else if(state==40) //Saving bytes...
{
//printf("Saving payload byte 0x%02X\n",buf[0]);
buffin[bi++]=buf[0];
dcs=dcs+buf[0];
if(bi>=len){state=50;}
}
else if(state==50) //Calculating the checksum..
{
state=0;
dcs=dcs+buf[0];
if(dcs)
{
printf("ERROR: Data Checksum Failed! (0x%02X)\n",dcs);
}else{
if(waitfor==PACKET){cstate=cstate|1;}
//printf("Good Packet: tfi=0x%02X, len=%d\n",tfi,len-1);
if(tfi==0xD5)
{
if(buffin[0]==0x03){printf("PN532 Version: %d.%d, features:%d\n",buffin[2],buffin[3],buffin[4]);}
if(buffin[0]==0x05)
{
printf("Status: Last Error:%d, Field:%d, Targets:%d, SAM Status:0x%02X\n",buffin[1],buffin[2],buffin[3],buffin[len-2]);
static char bitrates[255][10]={"106kbps","212kbps","424kbps"};
static char modtypes[255][100];
strcpy(modtypes[0x00],"Mifare, ISO/IEC14443-3 Type A, ISO/IEC14443-3 Type B, ISO/IEC18092 passive 106 kbps");
strcpy(modtypes[0x10],"FeliCa, ISO/IEC18092 passive 212/424 kbps");
strcpy(modtypes[0x01],"ISO/IEC18092 Active mode");
strcpy(modtypes[0x02],"Innovision Jewel tag");
if(buffin[3]==1){printf("Target %d: rx bps:%s, tx bps:%s, modulation type: %s.\n",buffin[4],bitrates[buffin[5]],bitrates[buffin[6]],modtypes[buffin[7]]);}
if(buffin[3]==2){printf("Target %d: rx bps:%s, tx bps:%s, modulation type: %s.\n",buffin[8],bitrates[buffin[9]],bitrates[buffin[10]],modtypes[buffin[11]]);}
}
if(buffin[0]==0x4B)
{
printf("FOUND %d CARDS!\n",buffin[1]);
//ONLY VALID FOR Mifare/ ISO type A 106KBPS:
int i,ii,iii;
i=0;ii=2;
while(i<buffin[1])
{
printf("Target # %d:", buffin[ii++]);
printf("SENS_RES=0x%02X%02X, ",buffin[ii],buffin[ii+1]);ii++;ii++;
printf("SEL_RES=0x%02X, ",buffin[ii++]);
printf("NFCIDLength=%d, ",buffin[ii++]);
printf("NFCID=");
iii=0;
while(iii<buffin[ii-1])
{
printf("%02X",buffin[ii+iii]);
iii++;
if(iii<buffin[ii-1]){printf(":");}
}
ii=ii+iii;
printf("\n");
i++;
}
}
//Just a debugging thing for printing out the contents of valid packets.
//int i=0;while(i<(len-1)){printf("0x%02X, ",buffin[i++]);}printf("\n");
}
else if(tfi==0x7F)
{
printf("Received error packet 0x7F with zero size.\n");
}else{
printf("ERROR: Got unknown %d byte packet with tfi=0x%02X!\n",len-1,tfi);
}
}
}
else
{
printf("Uhoh!\n");
}
//printf("Got byte 0x%02X, now state is %d\n",(unsigned char)buf[0],state);
}else{
printf("ERROR: bi=%d which is too big.. Starting over.\n",bi);
bi=0;
}
}else{
printf("ERROR %d while reading serial port: %s\n",errno,strerror(errno));
exit(-1);
}
}
usleep(1000);
}
return(0);
}
void init_rs232(void)
{
char *portname = "/dev/ttyUSB0";
fd = open (portname, O_RDWR | O_NOCTTY | O_SYNC);
if (fd < 0)
{
printf("error %d opening %s: %s", errno, portname, strerror (errno));
exit(-1);
}
struct termios tty;
memset (&tty, 0, sizeof tty);
if (tcgetattr (fd, &tty) != 0)
{
printf("error %d from tcgetattr(%s)\n", errno,strerror(errno));
exit(-1);
}
cfsetospeed (&tty, B115200);
cfsetispeed (&tty, B115200);
tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8; // 8-bit chars
// disable IGNBRK for mismatched speed tests; otherwise receive break
// as \000 chars
tty.c_iflag &= ~IGNBRK; // disable break processing
tty.c_lflag = 0; // no signaling chars, no echo,
// no canonical processing
tty.c_oflag = 0; // no remapping, no delays
tty.c_cc[VMIN] = 0; // read doesn't block
tty.c_cc[VTIME] = 0; // 0.5 seconds read timeout
tty.c_iflag &= ~(IXON | IXOFF | IXANY); // shut off xon/xoff ctrl
tty.c_cflag |= (CLOCAL | CREAD);// ignore modem controls,
// enable reading
tty.c_cflag &= ~(PARENB | PARODD); // shut off parity
tty.c_cflag |= 0; //This was parity
tty.c_cflag &= ~CSTOPB;
tty.c_cflag &= ~CRTSCTS;
if (tcsetattr (fd, TCSANOW, &tty) != 0)
{
printf("error %d from tcsetattr(%s)\n", errno,strerror(errno));
exit(-1);
}
}
void sendpacket(unsigned char * payload, int len)
{
int tfi;
static unsigned char buffer[66000];
int i,bo;
unsigned char lcs,dcs;
tfi=0xD4;
i=0;
bo=0;
while(i<=8){i++;buffer[bo++]=0xFF;} //Pre-padding.. 8-800 OK, 900 too much, 7 too little. Needs to be 0xFF I guess.. Probably wakes it up.
buffer[bo++]=0x00; //Preamble.
buffer[bo++]=0xFF; //Preamble.
len++;
lcs=-len; //Length Checksum.. (yes...)
buffer[bo++]=len;
buffer[bo++]=lcs;
buffer[bo++]=tfi;
dcs=tfi;
i=0;
while((i<65900)&&(i<(len-1)))
{
buffer[bo]=payload[i];
dcs=dcs+buffer[bo];
bo++;
i++;
}
dcs=(-dcs);
buffer[bo++]=dcs;
write(fd,buffer,bo);
//printf("Sent %d bytes\n",bo);
//printf("Whole packet: ");
//i=0;
//while(i<bo)
//{
// printf("0x%02X ",buffer[i]);
// i++;
//}
//printf("\n");
}
void sendcmd(char * payload) //Accepts space separated argument list like "0xFF 0x0A 255 'USERID' 0 0"
{ //strings are quoted in half quotes. half quotes inside a string are escaped \\'
int i,v; //full quotes inside a string are escaped like \"
static unsigned char buffer[1024]; //back slashes inside a string are escaped like \\\\ .
static int bo; //(The first escape or escape pair is for the C compiler, the second for this function:
bo=0; // The actual contents of the string are just \' and \\)
i=0; // Numeric formats supported are hex (0xNN), base ten (123), and octal (0377).
if(debug){printf("sendcmd: ");}
while(payload[i])
{
if((payload[i]!='\'')&&(payload[i]!=' '))
{
v=strtoul(&payload[i],NULL,0);
buffer[bo++]=v;
if(debug){printf("0x%02X, ",v);}
while(payload[i]>' '){i++;}
}
else if(payload[i]=='\'')
{
i++;
int keeprun;
keeprun=1;
while(keeprun)
{
if(payload[i]=='\\')
{
i++;
}else{
if(payload[i]=='\''){keeprun=0;}
}
if((keeprun)&&(payload[i]))
{
buffer[bo++]=payload[i];
if(debug){printf("%c",payload[i]);}
}
i++;
}
if(debug){printf(", ");}
}
else
{
i++;
}
}
if(debug){printf("\n");}
sendpacket(buffer,bo);
}