Problem reading and writing register to a pn532 with an arduino board

[Pascal Marois]

I've coded this part to read xram register of pn532 with libnfc 1.7.1

case 0x06: { //ReadRegister Page 76 

int address;

uint8_t value;

int j = 0;

for (int i = 0; i <= 10; i += 2) {

memcpy(&address, (int*) abtRxBuf + 7 + i, 2);

pn532_packetbuffer[0/*1*/] = address >> 8;

pn532_packetbuffer[1/*2*/] = address & 0xff;

Wire.write(pn532_packetbuffer, 2);

// read data packet

Wire.requestFrom(PN532_I2C_ADDRESS, 0x05);

j = 0;

while (Wire.available() && j < 6) {

answerSamConfig[j]/*value*/= Wire.read(); //pn532_packetbuffer[0];

//answerSamConfig[j] = value;

//Wire.write(value); Serial.write(value);

j++;

}

}

Wire.write(answerSamConfig, 5);

Serial.write(answerSamConfig, 5);

uint8_t dataSum = btDCS - sum_array(answerSamConfig, 5); //0x24;

writePostStuff(dataSum);

//        writeCommand(answerSamConfig, sizeof(answerSamConfig));

break;

}

I got this bad answer.

debug   libnfc.chip.pn53x       ReadRegister

debug   libnfc.bus.uart_win32   TX: 00 00 ff 06 fa d4 06 63 1e 63 1f 23 00

debug   libnfc.driver.pn532_uart        Read ACK

debug   libnfc.bus.uart_win32   Timeouts are set to 350 ms

debug   libnfc.bus.uart_win32   ReadFile

debug   libnfc.bus.uart_win32   RX: 00 00 ff 00 ff 00

debug   libnfc.chip.pn53x       PN53x ACKed

debug   libnfc.bus.uart_win32   Timeouts are set to 350 ms

debug   libnfc.bus.uart_win32   ReadFile

debug   libnfc.bus.uart_win32   RX: 00 00 ff 07 f9

debug   libnfc.driver.pn532_uart        Frame preamble+start code

debug   libnfc.driver.pn532_uart        Check Checksum Normal Frame, 07, f9

debug   libnfc.driver.pn532_uart        Get len from abtRxBf[3] - 2, 05

debug   libnfc.driver.pn532_uart        TFI + PD0 (CC+1)

debug   libnfc.bus.uart_win32   Timeouts are set to 350 ms

debug   libnfc.bus.uart_win32   ReadFile

debug   libnfc.bus.uart_win32   RX: d5 07

debug   libnfc.driver.pn532_uart        Check TFI d5

debug   libnfc.driver.pn532_uart        Check Command  07

debug   libnfc.driver.pn532_uart        Get len 05

debug   libnfc.bus.uart_win32   Timeouts are set to 350 ms

debug   libnfc.bus.uart_win32   ReadFile

debug   libnfc.bus.uart_win32   RX: 00 80 80 80 80

debug   libnfc.driver.pn532_uart        Wait 2 more bytes

debug   libnfc.bus.uart_win32   Timeouts are set to 350 ms

debug   libnfc.bus.uart_win32   ReadFile

debug   libnfc.bus.uart_win32   RX: 24 00

debug   libnfc.driver.pn532_uart        Check btDCS  24

debug   libnfc.driver.pn532_uart        Check Postamble  00

Received bits:

Found tag with

 UID: 00000000

ATQA: 0000

 SAK: 00

My question is : how to access pn532 register with an arduino ?

Many other command are working well in my code, this part is critical

Thank you