int main(int argc, char* argv[])
{
char aChar;
gz_clock_ena(GZ_CLK_5MHz, 0x00f); // Turn on a slow clock
printf("\nPress any key to stop test.");
scanf("%c", &aChar);
gz_clock_dis();
return 0;
}
ADCreader::ADCreader()
{
int ret = 0;
// set up ringbuffer
samples = new int[MAX_SAMPLES];
// pointer for incoming data
pIn = samples;
// pointer for outgoing data
pOut = samples;
// SPI constants
static const char *device = "/dev/spidev0.0";
mode = SPI_CPHA | SPI_CPOL;
bits = 8;
speed = 50000;
delay = 10;
drdy_GPIO = 22;
// open SPI device
fd = open(device, O_RDWR);
if (fd < 0)
pabort("can't open device");
/*
* spi mode
*/
ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
if (ret == -1)
pabort("can't set spi mode");
ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
if (ret == -1)
pabort("can't get spi mode");
/*
* bits per word
*/
ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't set bits per word");
ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't get bits per word");
/*
* max speed hz
*/
ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
if (ret == -1)
pabort("can't set max speed hz");
ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
if (ret == -1)
pabort("can't get max speed hz");
fprintf(stderr, "spi mode: %d\n", mode);
fprintf(stderr, "bits per word: %d\n", bits);
fprintf(stderr, "max speed: %d Hz (%d KHz)\n", speed, speed/1000);
// enable master clock for the AD
// divisor results in roughly 4.9MHz
// this also inits the general purpose IO
gz_clock_ena(GZ_CLK_5MHz,5);
// enables sysfs entry for the GPIO pin
gpio_export(drdy_GPIO);
// set to input
gpio_set_dir(drdy_GPIO,0);
// set interrupt detection to falling edge
gpio_set_edge(drdy_GPIO,"falling");
// get a file descriptor for the GPIO pin
sysfs_fd = gpio_fd_open(drdy_GPIO);
// resets the AD7705 so that it expects a write to the communication register
writeReset(fd);
// tell the AD7705 that the next write will be to the clock register
writeReg(fd,0x20);
// write 00001100 : CLOCKDIV=1,CLK=1,expects 4.9152MHz input clock
writeReg(fd,0x0C);
// tell the AD7705 that the next write will be the setup register
writeReg(fd,0x10);
// intiates a self calibration and then after that starts converting
writeReg(fd,0x40);
}
int main(int argc, char *argv[])
{
int ret = 0;
int fd;
int sysfs_fd;
int no_tty = !isatty( fileno(stdout) );
fd = open(device, O_RDWR);
if (fd < 0)
pabort("can't open device");
/*
* spi mode
*/
ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
if (ret == -1)
pabort("can't set spi mode");
ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
if (ret == -1)
pabort("can't get spi mode");
/*
* bits per word
*/
ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't set bits per word");
ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't get bits per word");
fprintf(stderr, "spi mode: %d\n", mode);
fprintf(stderr, "bits per word: %d\n", bits);
// enable master clock for the AD
// divisor results in roughly 4.9MHz
// this also inits the general purpose IO
gz_clock_ena(GZ_CLK_5MHz,5);
// enables sysfs entry for the GPIO pin
gpio_export(drdy_GPIO);
// set to input
gpio_set_dir(drdy_GPIO,0);
// set interrupt detection to falling edge
gpio_set_edge(drdy_GPIO,"falling");
// get a file descriptor for the GPIO pin
sysfs_fd = gpio_fd_open(drdy_GPIO);
// resets the AD7705 so that it expects a write to the communication register
printf("sending reset\n");
writeReset(fd);
// tell the AD7705 that the next write will be to the clock register
writeReg(fd,0x20);
// write 00001100 : CLOCKDIV=1,CLK=1,expects 4.9152MHz input clock
writeReg(fd,0x0C);
//channel1
writeReg(fd,0x11);
// intiates a self calibration and then after that starts converting
writeReg(fd,0x40);
ret = gpio_poll(sysfs_fd,1000);
if (ret<1) {
fprintf(stderr,"Poll error chennel1 set-up %d\n",ret);
}
//channel0
// tell the AD7705 that the next write will be the setup register
writeReg(fd,0x10);
// intiates a self calibration and then after that starts converting
writeReg(fd,0x40);
ret = gpio_poll(sysfs_fd,1000);
if (ret<1) {
fprintf(stderr,"Poll error chennel0 set-up %d\n",ret);
}
// we read data in an endless loop and display it
// this needs to run in a thread ideally
while (1) {
//channel0
// tell the AD7705 to read the data register (16 bits)
writeReg(fd,0x38);
ret = gpio_poll(sysfs_fd,1000);
if (ret<1) {
fprintf(stderr,"Poll error read data channel0 %d\n",ret);
}
// read the data register by performing two 8 bit reads
int value0 = readData(fd)-0x8000;
//channel1
// tell the AD7705 to read the data register (16 bits)
writeReg(fd,0x39);
ret = gpio_poll(sysfs_fd,1000);
if (ret<1) {
fprintf(stderr,"Poll error read data channel0 %d\n",ret);
}
// read the data register by performing two 8 bit reads
int value1 = readData(fd)-0x8000;
fprintf(stderr,"data0 = %d data1 = %d \r",value0,value1);
}
close(fd);
gpio_fd_close(sysfs_fd);
return ret;
}
int main(int argc, char* argv[])
{
initscr(); // initialize ncurses display
nodelay(stdscr, 1); // don't wait for key presses
noecho(); // don't echo key presses
gz_spi_set_width(2); // Pass blocks of 2 bytes on SPI
gz_clock_ena(GZ_CLK_5MHz, 0x02); // 2.5 MHz
erase();
outputs_off();
printw("Modulating PWMs.\n");
printw("Press 'n' for next test, any other key to stop.\n");
int key = 0;
while(1) {
exercise_pwms();
key = getch();
if (key != -1) {
break;
}
}
if (key == 'n') {
printw("Toggling all outputs.\n");
printw("Press 'n' for next test, any other key to stop.\n");
while(1) {
exercise_outputs(0xff, 0x00);
key = getch();
if (key != -1) {
break;
}
}
}
if (key == 'n') {
erase();
printw("Toggling alternate outputs.\n");
printw("Press 'n' for next test, any other key to stop.\n");
while(1) {
exercise_outputs(0xaa, 0x55);
key = getch();
if (key != -1) {
break;
}
}
}
if (key == 'n') {
erase();
printw("Walking outputs.\n");
printw("Press 'n' for next test, any other key to stop.\n");
unsigned char current = 0xfe;
while(1) {
exercise_outputs(current, (current << 1) | 0x01);
current = (current << 2) | 0x03;
if (current == 0xff) {
current = 0xfe;
}
key = getch();
if (key != -1) {
break;
}
}
}
if (key == 'n') {
erase();
curs_set(0); // Hide the cursor
printw("Reading inputs.\n");
printw("Press any key to stop.\n");
while(1) {
display_inputs();
key = getch();
if (key != -1) {
break;
}
}
move(getcury(stdscr) + 1 ,0);
curs_set(1);
refresh();
}
gz_spi_close(); // close SPI channel
erase();
reset_shell_mode(); // turn off ncurses
return 0;
}
static void writeReset(int fd)
{
int ret;
uint8_t tx1[5] = {0xff,0xff,0xff,0xff,0xff};
uint8_t rx1[5] = {0};
struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx1,
.rx_buf = (unsigned long)rx1,
.len = ARRAY_SIZE(tx1),
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = bits,
};
ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");
}
static void writeReg(int fd, uint8_t v)
{
int ret;
uint8_t tx1[1];
tx1[0] = v;
uint8_t rx1[1] = {0};
struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx1,
.rx_buf = (unsigned long)rx1,
.len = ARRAY_SIZE(tx1),
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = bits,
};
ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");
}
static uint8_t readReg(int fd)
{
int ret;
uint8_t tx1[1];
tx1[0] = 0;
uint8_t rx1[1] = {0};
struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx1,
.rx_buf = (unsigned long)rx1,
.len = ARRAY_SIZE(tx1),
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = 8,
};
ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");
return rx1[0];
}
static int readData(int fd)
{
int ret;
uint8_t tx1[2] = {0,0};
uint8_t rx1[2] = {0,0};
struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx1,
.rx_buf = (unsigned long)rx1,
.len = ARRAY_SIZE(tx1),
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = 8,
};
ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");
return (rx1[0]<<8)|(rx1[1]);
}
void setADC()
{
int ret = 0;
int no_tty = !isatty( fileno(stdout) );
fd = open(device, O_RDWR);
if (fd < 0)
pabort("can't open device");
/*
* spi mode
*/
ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
if (ret == -1)
pabort("can't set spi mode");
ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
if (ret == -1)
pabort("can't get spi mode");
/*
* bits per word
*/
ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't set bits per word");
ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't get bits per word");
/*
* max speed hz
*/
ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
if (ret == -1)
pabort("can't set max speed hz");
ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
if (ret == -1)
pabort("can't get max speed hz");
fprintf(stderr, "spi mode: %d\n", mode);
fprintf(stderr, "bits per word: %d\n", bits);
fprintf(stderr, "max speed: %d Hz (%d KHz)\n", speed, speed/1000);
// enable master clock for the AD
// divisor results in roughly 4.9MHz
gz_clock_ena(GZ_CLK_5MHz,5);
// resets the AD7705 so that it expects a write to the communication register
writeReset(fd);
// tell the AD7705 that the next write will be to the clock register
writeReg(fd,0x20);
// write 00001100 : CLOCKDIV=1,CLK=1,expects 4.9152MHz input clock
writeReg(fd,0x0C);
// tell the AD7705 that the next write will be the setup register
writeReg(fd,0x10);
// intiates a self calibration and then after that starts converting
writeReg(fd,0x40);
}
void ADCreader::run()
{
int ret = 0;
int fd;
int sysfs_fd;
int no_tty = !isatty( fileno(stdout) );
fd = open(device, O_RDWR);
if (fd < 0)
pabort("can't open device");
/*
* spi mode
*/
ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
if (ret == -1)
pabort("can't set spi mode");
ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
if (ret == -1)
pabort("can't get spi mode");
/*
* bits per word
*/
ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't set bits per word");
ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't get bits per word");
fprintf(stderr, "spi mode: %d\n", mode);
fprintf(stderr, "bits per word: %d\n", bits);
// enable master clock for the AD
// divisor results in roughly 4.9MHz
// this also inits the general purpose IO
gz_clock_ena(GZ_CLK_5MHz,5);
// enables sysfs entry for the GPIO pin
gpio_export(drdy_GPIO);
// set to input
gpio_set_dir(drdy_GPIO,0);
// set interrupt detection to falling edge
gpio_set_edge(drdy_GPIO,"falling");
// get a file descriptor for the GPIO pin
sysfs_fd = gpio_fd_open(drdy_GPIO);
// resets the AD7705 so that it expects a write to the communication register
printf("sending reset\n");
writeReset(fd);
// tell the AD7705 that the next write will be to the clock register
writeReg(fd,0x20);
// write 00001100 : CLOCKDIV=1,CLK=1,expects 4.9152MHz input clock
writeReg(fd,0x0C);
// tell the AD7705 that the next write will be the setup register
writeReg(fd,0x10);
// enable master clock for the AD
// divisor results in roughly 4.9MHz
// this also inits the general purpose IO
gz_clock_ena(GZ_CLK_5MHz,5);
// enables sysfs entry for the GPIO pin
gpio_export(drdy_GPIO);
// set to input
gpio_set_dir(drdy_GPIO,0);
// set interrupt detection to falling edge
gpio_set_edge(drdy_GPIO,"falling");
// get a file descriptor for the GPIO pin
sysfs_fd = gpio_fd_open(drdy_GPIO);
// resets the AD7705 so that it expects a write to the communication register
printf("sending reset\n");
writeReset(fd);
// tell the AD7705 that the next write will be to the clock register
writeReg(fd,0x20);
// write 00001100 : CLOCKDIV=1,CLK=1,expects 4.9152MHz input clock
writeReg(fd,0x0C);
// tell the AD7705 that the next write will be the setup register
writeReg(fd,0x10);
// intiates a self calibration and then after that starts converting
writeReg(fd,0x40);
// we read data in an endless loop and display it
// this needs to run in a thread ideally
// let's wait for data for max one second
ret = gpio_poll(sysfs_fd,1000);
if (ret<1) {
fprintf(stderr,"Poll error %d\n",ret);
}
// tell the AD7705 to read the data register (16 bits)
writeReg(fd,0x38);
// read the data register by performing two 8 bit reads
//acquire and store the value of resistance (presumably at clean air)
float init = readData(fd);
float vdif = ((init/32768)-1)*2.5; //translate the code into voltage to find Ain1(+)-Ain1(-)
float Ain = vdif + 0.964; //add Ain1(-) to find the actual voltage
float Rair = (4300*5/Ain)-4300; // reverse engineer the voltage divider to find the resistance
fprintf(stderr,"init = %f \t vdif= %f \t Ain=%f \t Rair = %f \n \n ", init, vdif, Ain, Rair);
running = 1;
while (running) {
// let's wait for data for max one second
ret = gpio_poll(sysfs_fd,1000);
if (ret<1) {
fprintf(stderr,"Poll error %d\n",ret);
}
// tell the AD7705 to read the data register (16 bits)
writeReg(fd,0x38);
// read the data register by performing two 8 bit reads
float value = readData(fd);
float vdifcurrent=((value/32768)-1)*2.5;
float Aincurrent = vdifcurrent + 0.964;
float Rcurrent = (4300*5/Aincurrent)-4300;
float Rratio = Rcurrent/Rair; //divide resistance found by resistance in fresh air
buffer[bindex-1] = Rratio; //store value in ring buffer
/* The following code has been used for debugging purgposes and is now commented out
float test = buffer[bindex-1];
fprintf(stderr,"data = %f \t vdiff=%f \t Ain=%f \t res ratio = %f \r ", value, vdifcurrent, Aincurrent, test);
*/
bindex = bindex++; // update buffer index
if(bindex == 20000000){
bindex = 0;
}
}
close(fd);
gpio_fd_close(sysfs_fd);
}