// default timeout of one second
boolean Adafruit_NFCShield_I2C::sendCommandCheckAck(uint8_t *cmd, uint8_t cmdlen, uint16_t timeout) {
uint16_t timer = 0;
// write the command
wiresendcommand(cmd, cmdlen);
// Wait for chip to say its ready!
while (wirereadstatus() != PN532_I2C_READY) {
if (timeout != 0) {
timer+=10;
if (timer > timeout)
return false;
}
delay(10);
}
#ifdef PN532DEBUG
Serial.println("IRQ received");
#endif
// read acknowledgement
if (!readackframe()) {
#ifdef PN532DEBUG
Serial.println("No ACK frame received!");
#endif
return false;
}
return true; // ack'd command
}
boolean Adafruit_NFCShield_I2C::waitUntilReady(uint16_t timeout) {
uint16_t timer = 0;
while(wirereadstatus() != PN532_I2C_READY) {
if (timeout != 0) {
timer += 10;
if (timer > timeout) {
return false;
}
}
delay(10);
}
return true;
}
boolean Adafruit_NFCShield_I2C::readPassiveTargetID(uint8_t cardbaudrate, uint8_t * uid, uint8_t * uidLength) {
pn532_packetbuffer[0] = PN532_COMMAND_INLISTPASSIVETARGET;
pn532_packetbuffer[1] = 1; // max 1 cards at once (we can set this to 2 later)
pn532_packetbuffer[2] = cardbaudrate;
if (! sendCommandCheckAck(pn532_packetbuffer, 3))
{
#ifdef PN532DEBUG
Serial.println("No card(s) read");
#endif
return 0x0; // no cards read
}
// Wait for a card to enter the field
uint8_t status = PN532_I2C_BUSY;
#ifdef PN532DEBUG
Serial.println("Waiting for IRQ (indicates card presence)");
#endif
while (wirereadstatus() != PN532_I2C_READY)
{
delay(10);
}
#ifdef PN532DEBUG
Serial.println("Found a card");
#endif
// read data packet
wirereaddata(pn532_packetbuffer, 20);
// check some basic stuff
/* ISO14443A card response should be in the following format:
byte Description
------------- ------------------------------------------
b0..6 Frame header and preamble
b7 Tags Found
b8 Tag Number (only one used in this example)
b9..10 SENS_RES
b11 SEL_RES
b12 NFCID Length
b13..NFCIDLen NFCID */
#ifdef MIFAREDEBUG
Serial.print("Found "); Serial.print(pn532_packetbuffer[7], DEC); Serial.println(" tags");
#endif
if (pn532_packetbuffer[7] != 1)
return 0;
uint16_t sens_res = pn532_packetbuffer[9];
sens_res <<= 8;
sens_res |= pn532_packetbuffer[10];
#ifdef MIFAREDEBUG
Serial.print("ATQA: 0x"); Serial.println(sens_res, HEX);
Serial.print("SAK: 0x"); Serial.println(pn532_packetbuffer[11], HEX);
#endif
/* Card appears to be Mifare Classic */
*uidLength = pn532_packetbuffer[12];
#ifdef MIFAREDEBUG
Serial.print("UID:");
#endif
for (uint8_t i=0; i < pn532_packetbuffer[12]; i++)
{
uid[i] = pn532_packetbuffer[13+i];
#ifdef MIFAREDEBUG
Serial.print(" 0x");Serial.print(uid[i], HEX);
#endif
}
#ifdef MIFAREDEBUG
Serial.println();
#endif
return 1;
}
