Dear Larry Bank,
thanks for reply. I am getting OK with same code (given below) using raspberry pi 3 but not with ORANGE PI ZERO and that is what upsetting me.
My code is below:
---------------------------------------------------------------------------------------------------------------------
/*
spidevlib.c - A user-space program to comunicate using spidev.
Gustavo Zamboni
*/
#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <getopt.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/types.h>
#include <linux/spi/spidev.h>
#include <string.h>
char buf[10];
char buf2[10];
struct spi_ioc_transfer xfer[2];
int spi_init(char filename[40])
{
int file;
__u8 mode=0, lsb, bits;
__u32 speed=1000000;
if ((file = open(filename,O_RDWR)) < 0)
{
printf("Failed to open the bus.");
/* ERROR HANDLING; you can check errno to see what went wrong */
//com_serial=0;
exit(1);
}
///////////////
// Verifications
///////////////
//possible modes: mode |= SPI_LOOP; mode |= SPI_CPHA; mode |= SPI_CPOL; mode |= SPI_LSB_FIRST; mode |= SPI_CS_HIGH; mode |= SPI_3WIRE; mode |= SPI_NO_CS; mode |= SPI_READY;
//multiple possibilities using |
mode = SPI_MODE_3;
//mode |= SPI_NO_CS;
//mode |= SPI_LSB_FIRST;
if (ioctl(file, SPI_IOC_WR_MODE, &mode)<0) {
perror("can't set spi mode");
// return;
}
if (ioctl(file, SPI_IOC_RD_MODE, &mode) < 0)
{
perror("SPI rd_mode");
// return;
}
if (ioctl(file, SPI_IOC_RD_LSB_FIRST, &lsb) < 0)
{
perror("SPI rd_lsb_fist");
// return;
}
//sunxi supports only 8 bits
if (ioctl(file, SPI_IOC_WR_BITS_PER_WORD, 8 ) <0)
{
perror("can't set bits per word");
// return;
}
if (ioctl(file, SPI_IOC_RD_BITS_PER_WORD, &bits) < 0)
{
perror("SPI bits_per_word");
// return;
}
if (ioctl(file, SPI_IOC_WR_MAX_SPEED_HZ, &speed)<0)
{
perror("can't set max speed hz");
// return;
}
if (ioctl(file, SPI_IOC_RD_MAX_SPEED_HZ, &speed) < 0)
{
perror("SPI max_speed_hz");
// return;
}
printf("%s: spi mode %d, %d bits %sper word, %d Hz max\n",filename, mode, bits, lsb ? "(lsb first) " : "", speed);
xfer[0].tx_buf = (unsigned long)buf;
xfer[0].len = 3; /* Length of command to write*/
xfer[0].cs_change = 0; /* Keep CS activated */
xfer[0].delay_usecs = 0, //delay in us
xfer[0].speed_hz = 2500000, //speed
xfer[0].bits_per_word = 8, // bites per word 8
xfer[1].rx_buf = (unsigned long) buf2;
xfer[1].len = 4; /* Length of Data to read */
xfer[1].cs_change = 0; /* Keep CS activated */
// xfer[0].delay_usecs = 0;
// xfer[0].speed_hz = 2500000;
// xfer[0].bits_per_word = 8;
return file;
}
char * spi_read_status(int add1,int nbytes,int file)
{
int status;
// mode2("/dev/spidev1.0");
// memset(buf, 0, sizeof buf);
// memset(buf2, 0, sizeof buf2);
buf[0] = add1;
// buf[1] = add1;
// buf[2] = add2;
xfer[0].tx_buf = (unsigned long)buf;
xfer[0].len = 1; /* Length of command to write*/
xfer[1].rx_buf = (unsigned long) buf2;
xfer[1].len = nbytes; /* Length of Data to read */
status = ioctl(file, SPI_IOC_MESSAGE(2), xfer);
if (status < 0)
{
perror("SPI_IOC_MESSAGE");
// return;
}
printf("status: %02x \n", buf2[0]);
// adc = (buf2[0] << 16) | (buf2[1] << 8) | buf2[2];
// volt = adc / 8388607 - 1;
// volt = volt * 2.5 / 1;
// printf("Volt: %lf\n", volt);
// com_serial=1;
// failcount=0;
// return buf2;
// for (int ret = 0; ret < 4; ret++) {
// if (!(ret % 6))
// puts("");
// printf("%.2X ", buf2[ret]);
// }
}
char * spi_read(int add1,int nbytes,int file)
{
int status;
double adc,volt;
//mode0("/dev/spidev1.0");
memset(buf, 0, sizeof buf);
memset(buf2, 0, sizeof buf2);
buf[0] = add1;
// buf[1] = add1;
// buf[2] = add2;
xfer[0].tx_buf = (unsigned long)buf;
xfer[0].len = 1; /* Length of command to write*/
xfer[1].rx_buf = (unsigned long) buf2;
xfer[1].len = nbytes; /* Length of Data to read */
status = ioctl(file, SPI_IOC_MESSAGE(2), xfer);
if (status < 0)
{
perror("SPI_IOC_MESSAGE");
// return;
}
printf("env: %02x \n", buf[0]);
printf("Data: %02x %02x %02x %02x\n", buf2[0], buf2[1], buf2[2], buf2[3]);
adc = (buf2[0] << 16) | (buf2[1] << 8) | buf2[2];
volt = adc / 8388607 - 1;
volt = volt * 2.5 / 1;
//printf("Volt: %lf %02x %02x\n", volt, buf2[3],buf2[4]);
// com_serial=1;
// failcount=0;
// return buf2;
// for (int ret = 0; ret < 4; ret++) {
// if (!(ret % 6))
// puts("");
// printf("%.2X ", buf2[ret]);
// }
}
void spi_write(int add,int d1,int d2,int d3,int nbytes,int file)
{
unsigned char buf[32];
int status;
// mode0("/dev/spidev1.0");
buf[0] = add;
buf[1] = d1;
buf[2] = d2;
buf[3] = d3;
xfer[0].tx_buf = (unsigned long)buf;
xfer[0].len = nbytes+1; /* Length of command to write*/
status = ioctl(file, SPI_IOC_MESSAGE(1), xfer);
if (status < 0)
{
perror("SPI_IOC_MESSAGE");
}
printf("write: %02x %02x %02x\n", buf[0], buf[1], buf[2]);
//printf("ret: %02x %02x %02x %02x\n", buf2[0], buf2[1], buf2[2], buf2[3]);
}
void main()
{
/* code */
char *buffer;
char buf[10];
int file;
file=spi_init("/dev/spidev1.0"); //dev
spi_write(0x09,0x80,0x13,0x00,2,file); usleep(10000);
spi_write(0x0a,0x80,0x33,0x00,2,file); usleep(10000);
spi_write(0x0b,0x80,0x53,0x00,2,file); usleep(10000);
spi_write(0x0c,0x80,0x73,0x00,2,file); usleep(10000);
spi_write(0x0d,0x80,0x93,0x00,2,file); usleep(10000);
spi_write(0x0e,0x80,0xa3,0x00,2,file); usleep(10000);
spi_write(0x0f,0x80,0xc3,0x00,2,file); usleep(10000);
// spi_write(0x07,0x00,0x00,0x44,3,file); usleep(10000);
spi_write(0x01,0x04,0x00,0x00,2,file); usleep(10000);
while(1)
{
// spi_read_status(0x42,1,file);
// usleep(125000);
spi_read(0x42,4,file);
usleep(125000);
}
close(file);
}
which version of OS you are using? because i am facing same problem in 5.38. do you get any solution? then please share with me because i am stuck on that.