void SPI::begin(int busNo,uint32_t spi_speed){
if(spiIsInitialized){
return;
}
/* set spidev accordingly to busNo like:
* busNo = 23 -> /dev/spidev2.3
*
* a bit messy but simple
* */
char device[] = "/dev/spidev0.0";
device[11] += (busNo / 10) % 10;
device[13] += busNo % 10;
if(this->fd >=0) // check whether spi is already open
{
close(this->fd);
this->fd=-1;
}
this->fd = open(device, O_RDWR);
if (this->fd < 0) throw SPIException("can't open device");
/*
{
perror("can't open device");
abort();
}*/
spiIsInitialized = true;
init(spi_speed);
}
SPI::SPI( int bus, int ce, uint8_t mode )
{
std::stringstream devname;
devname << SPIDEV_PREFIX << bus << "." << ce;
this->fd = open(devname.str().c_str(), O_RDWR);
if( this->fd < 0 ) {
throw SPIException(string("Can't open spidev: ") + devname.str() );
}
// SPIモードセット
if( ioctl(this->fd, SPI_IOC_WR_MODE, &mode) < 0 ) {
throw SPIException(string( "SPI_IOC_WR_MODE failed"));
}
// パラメータ初期値セット
this->bits_per_word = 8; // 8ビット
this->cs_change = LOW; // Active Low
this->speed = 1000000; // 1MHz
this->delay_usecs = 0; // ディレイ0
}
void SPI::init(uint32_t speed)
{
uint8_t bits = RF24_SPIDEV_BITS;
uint8_t mode = 0;
int ret;
/*
* spi mode
*/
ret = ioctl(this->fd, SPI_IOC_WR_MODE, &mode);
if (ret == -1) throw SPIException("cant set WR spi mode");
/*{
perror("can't set spi mode");
abort();
}*/
ret = ioctl(this->fd, SPI_IOC_RD_MODE, &mode);
if (ret == -1) throw SPIException("can't set RD spi mode");
/*{
perror("can't set spi mode");
abort();
}*/
/*
* bits per word
*/
ret = ioctl(this->fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
if (ret == -1) throw SPIException("can't set WR bits per word");
/*{
perror("can't set bits per word");
abort();
}*/
ret = ioctl(this->fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
if (ret == -1) throw SPIException("can't set RD bits per word");
/*{
perror("can't set bits per word");
abort();
}*/
/*
* max speed hz
*/
ret = ioctl(this->fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
if (ret == -1) throw SPIException("can't WR set max speed hz");
/*{
perror("can't set max speed hz");
abort();
}*/
ret = ioctl(this->fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
if (ret == -1) throw SPIException("can't RD set max speed hz");
/*{
perror("can't set max speed hz");
abort();
}*/
_spi_speed=speed;
}
void SPI::transfernb(char* tbuf, char* rbuf, uint32_t len)
{
struct spi_ioc_transfer tr;
memset(&tr, 0, sizeof(tr));
tr.tx_buf = (unsigned long)tbuf;
tr.rx_buf = (unsigned long)rbuf;
tr.len = len;
tr.speed_hz = _spi_speed; //RF24_SPIDEV_SPEED;
tr.delay_usecs = 0;
tr.bits_per_word = RF24_SPIDEV_BITS;
tr.cs_change = 0;
int ret;
ret = ioctl(this->fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1) throw SPIException("can't send spi message");
/*{
perror("can't send spi message");
abort();
}*/
}
uint8_t *SPI::transfer( int len , uint8_t *txbuf)
{
struct spi_ioc_transfer send;
uint8_t *rxbuf = new uint8_t[len];
send.tx_buf = (unsigned long)txbuf;
send.rx_buf = (unsigned long)rxbuf;
send.len = len;
send.delay_usecs = this->delay_usecs;
send.speed_hz = this->speed;
send.bits_per_word = this->bits_per_word;
send.cs_change = this->cs_change;
errno = 0;
int r = ioctl( this->fd, SPI_IOC_MESSAGE(1), &send );
printf("errno : %d\n", errno);
if( r < 1 ) {
delete(rxbuf);
throw SPIException(string("SPI transfer error"));
}
return rxbuf;
}
uint8_t SPI::transfer(uint8_t tx)
{
struct spi_ioc_transfer tr;
memset(&tr, 0, sizeof(tr));
tr.tx_buf = (unsigned long)&tx;
uint8_t rx;
tr.rx_buf = (unsigned long)℞
tr.len = sizeof(tx);
tr.speed_hz = _spi_speed; //RF24_SPIDEV_SPEED;
tr.delay_usecs = 0;
tr.bits_per_word = RF24_SPIDEV_BITS;
tr.cs_change = 0;
int ret;
ret = ioctl(this->fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1) throw SPIException("can't send spi message");
/*{
perror("can't send spi message");
abort();
}*/
return rx;
}
