MFRC 522 with ATmega8. Mifare Classic 1K won't authenticate - nfc

Question

I have a problem with an ATmega8 and Mifare RC-522 based NFC/RFID controller.
I'm using this library and I've managed to read the UID of a card.
However, I'd like to also read and write other parts of the card but whenever I try to use the MFRC522_Auth function I don't get the idle interrupt which I should, instead it gives me LoAlertIrq saying that FIFObuffer is almost empty.
Here are the docs for the reader and the card, and below are relevant parts of my code.
main.c :
byte = mfrc522_request(PICC_REQALL,str);
if(byte == CARD_FOUND)
{
byte = mfrc522_get_card_serial(str);
if(byte == CARD_FOUND)
{
byte = mfrc522_auth(PICC_AUTHENT1A, 7, sectorKeyA, str);
if( (byte == CARD_FOUND) )
{
byte = MFRC522_Read1(4, str);
if(byte == CARD_FOUND)
{
//write content of that block
}
}
}
Relevant functions from the library :
void mfrc522_write(uint8_t reg, uint8_t data)
{
ENABLE_CHIP();
spi_transmit((reg<<1)&0x7E);
spi_transmit(data);
DISABLE_CHIP();
}
uint8_t mfrc522_read(uint8_t reg)
{
uint8_t data;
ENABLE_CHIP();
spi_transmit(((reg<<1)&0x7E)|0x80);
data = spi_transmit(0x00);
DISABLE_CHIP();
return data;
}
uint8_t mfrc522_to_card(uint8_t cmd, uint8_t *send_data, uint8_t send_data_len, uint8_t *back_data, uint32_t *back_data_len)
{
uint8_t status = 0;
uint8_t irqEn = 0x00;
uint8_t waitIRq = 0x00;
uint8_t lastBits;
uint8_t n;
uint8_t tmp;
uint32_t i;
switch (cmd)
{
case MFAuthent_CMD: //Certification cards close
{
irqEn = 0x12;
waitIRq = 0x10;
break;
}
case Transceive_CMD: //Transmit FIFO data
{
irqEn = 0x77;
waitIRq = 0x30;
break;
}
default:
break;
}
mfrc522_write(ComIEnReg, irqEn|0x80); //Interrupt request
n=mfrc522_read(ComIrqReg);
mfrc522_write(ComIrqReg,n&(~0x80));//clear all interrupt bits
n=mfrc522_read(FIFOLevelReg);
mfrc522_write(FIFOLevelReg,n|0x80);//flush FIFO data
// mfrc522_write(CommandReg, Idle_CMD); //NO action; Cancel the current cmd???
n=mfrc522_read(CommandReg);
mfrc522_write(CommandReg,n|0x00);
//Writing data to the FIFO
for (i=0; i<send_data_len; i++)
{
mfrc522_write(FIFODataReg, send_data[i]);
}
//Execute the cmd
mfrc522_write(CommandReg, cmd);
if (cmd == Transceive_CMD)
{
n=mfrc522_read(BitFramingReg);
mfrc522_write(BitFramingReg,n|0x80);
}
//Waiting to receive data to complete
i = 2000; //i according to the clock frequency adjustment, the operator M1 card maximum waiting time 25ms???
while (1) {
n = mfrc522_read(ComIrqReg); // ComIrqReg[7..0] bits are: Set1 TxIRq RxIRq IdleIRq HiAlertIRq LoAlertIRq ErrIRq TimerIRq
if (n & waitIRq) { // One of the interrupts that signal success has been set.
break;
}
if (n & 0x01) { // Timer interrupt - nothing received in 25ms
// return 6; //debug purpose
if (cmd == MFAuthent_CMD) {
LCD_Clear();
LCD_WriteTextXY(1, 3, LCD_itoa( mfrc522_read(ComIrqReg) ) );
_delay_ms(2500);
}
break;
}
if (--i == 0) { // The emergency break. If all other condions fail we will eventually terminate on this one after 35.7ms. Communication with the MFRC522 might be down.
if (cmd == MFAuthent_CMD) {
LCD_Clear();
LCD_WriteTextXY(1, 3, LCD_itoa( mfrc522_read(ComIrqReg) ) );
_delay_ms(2500);
}
break;
}
}
tmp=mfrc522_read(BitFramingReg);
mfrc522_write(BitFramingReg,tmp&(~0x80));
if (i != 0)
{
if(!(mfrc522_read(ErrorReg) & 0x1B)) //BufferOvfl Collerr CRCErr ProtecolErr
{
status = CARD_FOUND;
if (n & irqEn & 0x01)
{
status = CARD_NOT_FOUND; //??
}
if (cmd == Transceive_CMD)
{
n = mfrc522_read(FIFOLevelReg);
lastBits = mfrc522_read(ControlReg) & 0x07;
if (lastBits)
{
*back_data_len = (n-1)*8 + lastBits;
}
else
{
*back_data_len = n*8;
}
if (n == 0)
{
n = 1;
}
if (n > MAX_LEN)
{
n = MAX_LEN;
}
//Reading the received data in FIFO
for (i=0; i<n; i++)
{
back_data[i] = mfrc522_read(FIFODataReg);
}
}
}
if (cmd == MFAuthent_CMD) {
LCD_WriteTextXY(1, 10, LCD_itoa16( mfrc522_read(Status2Reg) ) );
_delay_ms(2500);
}
} else status = 9;
return status;
}
uint8_t mfrc522_get_card_serial(uint8_t * serial_out)
{
uint8_t status;
uint8_t i;
uint8_t serNumCheck=0;
uint32_t unLen;
mfrc522_write(BitFramingReg, 0x00); //TxLastBists = BitFramingReg[2..0]
serial_out[0] = PICC_ANTICOLL;
serial_out[1] = 0x20;
status = mfrc522_to_card(Transceive_CMD, serial_out, 2, serial_out, &unLen);
if (status == CARD_FOUND)
{
//Check card serial number
for (i=0; i<4; i++)
{
serNumCheck ^= serial_out[i];
}
if (serNumCheck != serial_out[i])
{
status = ERROR;
}
}
return status;
}
uint8_t mfrc522_auth(uint8_t authMode, uint8_t BlockAddr, uint8_t *Sectorkey, uint8_t *serNum)
{
uint8_t status;
uint32_t recvBits;
uint8_t i;
uint8_t buff[12];
// Validate instruction block address + sector + password + card serial number
buff[0] = authMode;
buff[1] = BlockAddr;
for (i=0; i<6; i++)
{
buff[i+2] = 0xFF /**(Sectorkey+i)*/;
}
for (i=0; i<4; i++)
{
buff[i+8] = *(serNum+i);
}
status = mfrc522_to_card(MFAuthent_CMD, buff, 12, buff, &recvBits);
return status;
}
uint8_t MFRC522_Read1(uint8_t blockAddr, uint8_t *recvData)
{
uint8_t status = 0;
uint8_t unLen, efa;
recvData[0] = PICC_READ;
recvData[1] = blockAddr;
CalculateCRC(recvData, 2, &recvData);
status = mfrc522_to_card(Transceive_CMD, recvData, 4, recvData, &unLen);
if ((status != CARD_FOUND)|| (unLen != 0x90))
{
status = ERROR;
}
return status;
}
uint8_t CalculateCRC(uint8_t *pIndata, uint8_t len, uint8_t *pOutData)
{
uint8_t i, n;
uint8_t status = 0;
n = mfrc522_read(DivIrqReg);
mfrc522_write(DivIrqReg,n&(~0x04)); //CRCIrq = 0
n = mfrc522_read(FIFOLevelReg); //FIFO
mfrc522_write(FIFOLevelReg, n|0x80);
//Write_MFRC522(CommandReg, PCD_IDLE);
// Write data to the FIFO
for (i=0; i<len; i++)
{
mfrc522_write(FIFODataReg, *(pIndata+i));
}
mfrc522_write(CommandReg, CalcCRC_CMD);
// Read the CRC calculation result
i = 0xFF;
while(1){
n = mfrc522_read(DivIrqReg);
if (n & 0x04) {
break;
}
if (--i != 0) {
return 7;
}
}
// Read the CRC calculation result
pOutData[3] = mfrc522_read(CRCResultReg_2);
pOutData[4] = mfrc522_read(CRCResultReg_1);
return status = 0;
}