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@avtehnik
Created November 4, 2015 07:58
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/*
* ----------------------------------------------------------------------------
* This is a MFRC522 library example; see https://github.com/miguelbalboa/rfid
* for further details and other examples.
*
* NOTE: The library file MFRC522.h has a lot of useful info. Please read it.
*
* Released into the public domain.
* ----------------------------------------------------------------------------
* Example sketch/program showing how to read data from a PICC (that is: a RFID
* Tag or Card) using a MFRC522 based RFID Reader on the Arduino SPI interface.
*
* When the Arduino and the MFRC522 module are connected (see the pin layout
* below), load this sketch into Arduino IDE then verify/compile and upload it.
* To see the output: use Tools, Serial Monitor of the IDE (hit Ctrl+Shft+M).
* When you present a PICC (that is: a RFID Tag or Card) at reading distance
* of the MFRC522 Reader/PCD, the serial output will show the ID/UID, type and
* any data blocks it can read. Note: you may see "Timeout in communication"
* messages when removing the PICC from reading distance too early.
*
* If your reader supports it, this sketch/program will read all the PICCs
* presented (that is: multiple tag reading). So if you stack two or more
* PICCs on top of each other and present them to the reader, it will first
* output all details of the first and then the next PICC. Note that this
* may take some time as all data blocks are dumped, so keep the PICCs at
* reading distance until complete.
*
* Typical pin layout used:
* -----------------------------------------------------------------------------------------
* MFRC522 Arduino Arduino Arduino Arduino Arduino
* Reader/PCD Uno Mega Nano v3 Leonardo/Micro Pro Micro
* Signal Pin Pin Pin Pin Pin Pin
* -----------------------------------------------------------------------------------------
* RST/Reset RST 9 5 D9 RESET/ICSP-5 RST
* SPI SS SDA(SS) 10 53 D10 10 10
* SPI MOSI MOSI 11 / ICSP-4 51 D11 ICSP-4 16
* SPI MISO MISO 12 / ICSP-1 50 D12 ICSP-1 14
* SPI SCK SCK 13 / ICSP-3 52 D13 ICSP-3 15
*/
#include <SPI.h>
#include <MFRC522.h>
#define RST_PIN 9 //
#define SS_PIN 10 //
MFRC522 mfrc522(SS_PIN, RST_PIN); // Create MFRC522 instance
void setup() {
pinMode(10, OUTPUT);
Serial.begin(9600); // Initialize serial communications with the PC
while (!Serial); // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)
SPI.begin(); // Init SPI bus
pinMode(10, OUTPUT);
SPI.setClockDivider(SPI_CLOCK_DIV128);
byte tmp;
mfrc522.PCD_WriteRegister(mfrc522.TPrescalerReg, 0x3E); // TPreScaler = TModeReg[3..0]:TPrescalerReg, ie 0x0A9 = 169 => f_timer=40kHz, ie a timer period of 25�s.
tmp = mfrc522.PCD_ReadRegister(mfrc522.TPrescalerReg);
Serial.print("TPrescalerReg ");
Serial.println(tmp, HEX);
mfrc522.PCD_WriteRegister(mfrc522.TReloadRegH, 0); // Reload timer with 0x3E8 = 1000, ie 25ms before timeout.
tmp = mfrc522.PCD_ReadRegister(mfrc522.TReloadRegH);
Serial.print("TReloadRegH ");
Serial.println(tmp, HEX);
mfrc522.PCD_WriteRegister(mfrc522.TReloadRegL, 30);
tmp = mfrc522.PCD_ReadRegister(mfrc522.TReloadRegL);
Serial.print("TReloadRegL ");
Serial.println(tmp, HEX);
mfrc522.PCD_WriteRegister(mfrc522.ModeReg, 0x3D); // Default 0x3F. Set the preset value for the CRC coprocessor for the CalcCRC command to 0x6363 (ISO 14443-3 part 6.2.4)
tmp = mfrc522.PCD_ReadRegister(mfrc522.ModeReg);
Serial.print("ModeReg ");
Serial.println(tmp, HEX);
tmp = mfrc522.PCD_ReadRegister(mfrc522.VersionReg);
Serial.print("VersionReg ");
Serial.println(tmp, HEX);
mfrc522.PCD_Init(); // Init MFRC522
ShowReaderDetails(); // Show details of PCD - MFRC522 Card Reader details
Serial.println(F("Scan PICC to see UID, type, and data blocks..."));
}
void loop() {
// Look for new cards
if ( ! mfrc522.PICC_IsNewCardPresent()) {
return;
}
// Select one of the cards
if ( ! mfrc522.PICC_ReadCardSerial()) {
return;
}
// Dump debug info about the card; PICC_HaltA() is automatically called
mfrc522.PICC_DumpToSerial(&(mfrc522.uid));
}
void ShowReaderDetails() {
// Get the MFRC522 software version
byte v = mfrc522.PCD_ReadRegister(mfrc522.VersionReg);
Serial.print(F("MFRC522 Software Version: 0x"));
Serial.print(v, HEX);
if (v == 0x91)
Serial.print(F(" = v1.0"));
else if (v == 0x92)
Serial.print(F(" = v2.0"));
else
Serial.print(F(" (unknown)"));
Serial.println("");
// When 0x00 or 0xFF is returned, communication probably failed
if ((v == 0x00) || (v == 0xFF)) {
Serial.println(F("WARNING: Communication failure, is the MFRC522 properly connected?"));
}
}
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