I am working on a project to communicate with PN532 nfc reader.
The reader work just fine with arduino code using SPI.
Below is the library I used to read and write data from PN532
https://github.com/adafruit/Adafruit-PN532
Now I switched to stm32 board I am using.
I have setup below and this is pretty much like what arduino code is using.
Below is the code I am currently using and I am stuck at write then receiving part.
#include "omo_driver_pn532.h"
#include <string.h>
const uint8_t pn532ack[] = {0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00};
uint8_t pn532response_firmwarevers[] = {0x00, 0x00, 0xFF, 0x06, 0xFA, 0xD5};
#define PN532_PACKBUFFSIZ 64
uint8_t pn532_packetbuffer[PN532_PACKBUFFSIZ];
OMO_PN532::OMO_PN532(SPI_HandleTypeDef* hspi, GPIO_TypeDef* GPIO, uint16_t ss)
{
_hspi = hspi;
_ssGPIO = GPIO;
_ssPin = ss;
slaveDeselect(); //SS pin default high
}
void OMO_PN532::begin(void)
{
pn532_packetbuffer[0] = PN532_COMMAND_GETFIRMWAREVERSION;
sendCommandCheckAck(pn532_packetbuffer, 1);
slaveDeselect();
}
uint32_t OMO_PN532::getFirmwareVersion(void)
{
uint32_t response;
pn532_packetbuffer[0] = PN532_COMMAND_GETFIRMWAREVERSION;
//Sending : 0x0, 0x0, 0xFF, 0x2, 0xFE, 0xD4, 0x2, 0x2A, 0x0,
//Reading: 0x0 0x0 0xFF 0x6 0xFA 0xD5 0x3 0x32 0x1 0x6 0x7 0xE8
sendCommandCheckAck(pn532_packetbuffer, 1);
// read data packet
readdata(pn532_packetbuffer, 12);
int offset = 7;
response = pn532_packetbuffer[offset++];
response <<= 8;
response |= pn532_packetbuffer[offset++];
response <<= 8;
response |= pn532_packetbuffer[offset++];
response <<= 8;
response |= pn532_packetbuffer[offset++];
return response;
}
/**************************************************************************/
/*!
@brief Sends a command and waits a specified period for the ACK
@param cmd Pointer to the command buffer
@param cmdlen The size of the command in bytes
@param timeout timeout before giving up
@returns 1 if everything is OK, 0 if timeout occured before an
ACK was recieved
*/
/**************************************************************************/
// default timeout of one second
bool OMO_PN532::sendCommandCheckAck(uint8_t *cmd, uint8_t cmdlen,
uint16_t timeout) {
// uint16_t timer = 0;
// write the command
writecommand(cmd, cmdlen);
// Wait for chip to say its ready!
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
// read acknowledgement
if (!readack()) {
return false;
}
return true; // ack'd command
}
/**************************************************************************/
/*!
@brief Reads n bytes of data from the PN532 via SPI or I2C.
@param buff Pointer to the buffer where data will be written
@param n Number of bytes to be read
*/
/**************************************************************************/
void OMO_PN532::readdata(uint8_t *buff, uint8_t n) {
uint8_t cmd = PN532_SPI_DATAREAD;
slaveSelect();
HAL_Delay(1);
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
HAL_SPI_Transmit(_hspi, &cmd, 1, 10);
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
HAL_SPI_Receive(_hspi, buff, n, 10);
slaveDeselect();
}
void OMO_PN532::writecommand(uint8_t *cmd, uint8_t cmdlen)
{
//Sending : 0x0, 0x0, 0xFF, 0x2, 0xFE, 0xD4, 0x2, 0x2A, 0x0,
// SPI command write.
uint8_t checksum;
uint8_t packet[PN532_PACKBUFFSIZ];
uint8_t *p = packet;
cmdlen++;
p[0] = PN532_SPI_DATAWRITE;
p++;
p[0] = PN532_PREAMBLE;
p++;
p[0] = PN532_STARTCODE1;
p++;
p[0] = PN532_STARTCODE2;
p++;
checksum = PN532_PREAMBLE + PN532_STARTCODE1 + PN532_STARTCODE2;
p[0] = cmdlen;
p++;
p[0] = ~cmdlen + 1;
p++;
p[0] = PN532_HOSTTOPN532;
p++;
checksum += PN532_HOSTTOPN532;
for (uint8_t i = 0; i < cmdlen - 1; i++) {
p[0] = cmd[i];
p++;
checksum += cmd[i];
}
p[0] = ~checksum;
p++;
p[0] = PN532_POSTAMBLE;
p++;
//spi_dev->write(packet, 8 + cmdlen);
slaveSelect();
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
HAL_SPI_Transmit(_hspi, (uint8_t *)packet, 8+cmdlen, 10);
slaveDeselect();
}
/**************************************************************************/
/*!
@brief Tries to read the SPI or I2C ACK signal
*/
/**************************************************************************/
bool OMO_PN532::readack() {
uint8_t ackbuff[6];
uint8_t cmd = PN532_SPI_DATAREAD;
slaveSelect();
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
HAL_SPI_Transmit(_hspi, (uint8_t *)cmd, 1, 10);
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
HAL_SPI_Receive(_hspi, ackbuff, 6, 10);
slaveDeselect();
return (0 == memcmp((char *)ackbuff, (char *)pn532ack, 6));
}
void OMO_PN532::slaveSelect(void)
{
HAL_GPIO_WritePin(_ssGPIO, _ssPin, GPIO_PIN_RESET);
}
void OMO_PN532::slaveDeselect(void)
{
HAL_GPIO_WritePin(_ssGPIO, _ssPin, GPIO_PIN_SET);
}
In this part, I am sending just 0x03 in the beginning then try to receive 6 bytes from PN532 however the scope shows entirely different thing
#define PN532_SPI_DATAREAD (0x03)
void OMO_PN532::readdata(uint8_t *buff, uint8_t n) {
uint8_t cmd = PN532_SPI_DATAREAD;
//spi_dev->write_then_read(&cmd, 1, buff, n);
slaveSelect();
HAL_Delay(1);
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
HAL_SPI_Transmit(_hspi, &cmd, 1, 10);
while(HAL_SPI_GetState(_hspi) != HAL_SPI_STATE_READY);
HAL_SPI_Receive(_hspi, buff, n, 10);
slaveDeselect();
}Below scope captured from MOSI (Green) and SCK (Yello) pins during below code debug.
