void ADCreader::run()
{
running = true;
while (running) {
// let's wait for data for max one second
int 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
int value = readData(fd)-0x8000;
*pIn = value;
if (pIn == (&samples[MAX_SAMPLES-1]))
pIn = samples;
else
pIn++;
}
close(fd);
gpio_fd_close(sysfs_fd);
}
static void post_init(struct v7 *v7) {
sj_prompt_init(v7);
do {
/*
* Now waiting until mongoose has active connections
* and there are active gpio ISR and then exiting
* TODO(alashkin): change this to something smart
*/
} while ((mongoose_poll(100) || gpio_poll()) && !sj_please_quit);
mongoose_destroy();
}
static int lua_gpio_poll(lua_State *L) {
gpio_t *gpio;
int timeout_ms;
int ret;
gpio = luaL_checkudata(L, 1, "periphery.GPIO");
lua_gpio_checktype(L, 2, LUA_TNUMBER);
timeout_ms = lua_tointeger(L, 2);
if ((ret = gpio_poll(gpio, timeout_ms)) < 0)
return lua_gpio_error(L, ret, gpio_errno(gpio), "Error: %s", gpio_errmsg(gpio));
lua_pushboolean(L, ret > 0);
return 1;
}
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;
}
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);
}
