/*
Reading multiple RFID tags, simultaneously!
By: Nathan Seidle @ SparkFun Electronics
Date: October 3rd, 2016
https://github.com/sparkfun/Simultaneou … Tag_Reader
Constantly reads and outputs any tags heard
If using the Simultaneous RFID Tag Reader (SRTR) shield, make sure the serial slide
switch is in the ‘SW-UART’ position
*/
#include <SoftwareSerial.h> //Used for transmitting to the device
SoftwareSerial softSerial(2, 3); //RX, TX
#include “SparkFun_UHF_RFID_Reader.h” //Library for controlling the M6E Nano module
RFID nano; //Create instance
void setup()
{
Serial.begin(115200);
while (!Serial); //Wait for the serial port to come online
if (setupNano(38400) == false) //Configure nano to run at 38400bps
{
Serial.println(F(“Module failed to respond. Please check wiring.”));
while (1); //Freeze!
}
nano.setRegion(REGION_NORTHAMERICA); //Set to North America
nano.setReadPower(500); //5.00 dBm. Higher values may caues USB port to brown out
//Max Read TX Power is 27.00 dBm and may cause temperature-limit throttling
Serial.println(F(“Press a key to begin scanning for tags.”));
while (!Serial.available()); //Wait for user to send a character
Serial.read(); //Throw away the user’s character
Serial.println(“OK”); //Not in original example code
nano.startReading(); //Begin scanning for tags
Serial.println(“Start reading”); //Not in original example code
}
void loop()
{
//Original example doesn’t have the following from here
if (!softSerial.available()){
Serial.println(“softSerial not available”);
delay (2000);
}
Serial.println(“Check nano”);
while (nano.check() == false){
Serial.println(“Nano check false”);
delay(1000);
}
// to here
if (nano.check() == true) //Check to see if any new data has come in from module
{
// Serial.println(“Nano check true”); //Not in original example code
byte responseType = nano.parseResponse(); //Break response into tag ID, RSSI, frequency, and timestamp
if (responseType == RESPONSE_IS_KEEPALIVE)
{
Serial.println(F(“Scanning”));
}
else if (responseType == RESPONSE_IS_TAGFOUND)
{
//If we have a full record we can pull out the fun bits
int rssi = nano.getTagRSSI(); //Get the RSSI for this tag read
long freq = nano.getTagFreq(); //Get the frequency this tag was detected at
long timeStamp = nano.getTagTimestamp(); //Get the time this was read, (ms) since last keep-alive message
byte tagEPCBytes = nano.getTagEPCBytes(); //Get the number of bytes of EPC from response
Serial.print(F(" rssi["));
Serial.print(rssi);
Serial.print(F(“]”));
Serial.print(F(" freq["));
Serial.print(freq);
Serial.print(F(“]”));
Serial.print(F(" time["));
Serial.print(timeStamp);
Serial.print(F(“]”));
//Print EPC bytes, this is a subsection of bytes from the response/msg array
Serial.print(F(" epc["));
for (byte x = 0 ; x < tagEPCBytes ; x++)
{
if (nano.msg[31 + x] < 0x10) Serial.print(F(“0”)); //Pretty print
Serial.print(nano.msg[31 + x], HEX);
Serial.print(F(" "));
}
Serial.print(F(“]”));
Serial.println();
}
else if (responseType == ERROR_CORRUPT_RESPONSE)
{
Serial.println(“Bad CRC”);
}
else
{
//Unknown response
Serial.print(“Unknown error”);
}
}
}
//Gracefully handles a reader that is already configured and already reading continuously
//Because Stream does not have a .begin() we have to do this outside the library
boolean setupNano(long baudRate)
{
nano.begin(softSerial); //Tell the library to communicate over software serial port
//Test to see if we are already connected to a module
//This would be the case if the Arduino has been reprogrammed and the module has stayed powered
softSerial.begin(baudRate); //For this test, assume module is already at our desired baud rate
while (softSerial.isListening() == false); //Wait for port to open
//About 200ms from power on the module will send its firmware version at 115200. We need to ignore this.
while (softSerial.available()) softSerial.read();
nano.getVersion();
if (nano.msg[0] == ERROR_WRONG_OPCODE_RESPONSE)
{
//This happens if the baud rate is correct but the module is doing a ccontinuous read
nano.stopReading();
Serial.println(F(“Module continuously reading. Asking it to stop…”));
delay(1500);
}
else
{
//The module did not respond so assume it’s just been powered on and communicating at 115200bps
softSerial.begin(115200); //Start software serial at 115200
nano.setBaud(baudRate); //Tell the module to go to the chosen baud rate. Ignore the response msg
softSerial.begin(baudRate); //Start the software serial port, this time at user’s chosen baud rate
delay(250);
}
//Test the connection
nano.getVersion();
if (nano.msg[0] != ALL_GOOD) return (false); //Something is not right
//The M6E has these settings no matter what
nano.setTagProtocol(); //Set protocol to GEN2
nano.setAntennaPort(); //Set TX/RX antenna ports to 1
return (true); //We are ready to rock
}
