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burn in logging and graphing

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William Clark 2024-05-14 13:20:32 +01:00
parent 716d41b792
commit b3783a13da
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README.md
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@ -93,3 +93,76 @@ gas resistance: 14702.868852 Ohm
```
Note: Do not trust the gas resistance measurement if `heat_stab_r` is not `1`.
## Burn-in / logging
See file `example/log.c`
![Graph of gas resistance measured over time](.gitea/gas.png)
![Graph of temperature measured over time](.gitea/temp.png)
![Graph of pressure measured over time](.gitea/press.png)
![Graph of humidity measured over time](.gitea/hum.png)
Compile and run
```sh
stdbuf -o0 ./bme680 2>&1 | tee -a log.txt
```
This will give an output similar to this:
```
2024-05-14T13:03:02+0100 20.8916 99836.7 68.6594 7180.73 1
2024-05-14T13:04:03+0100 20.8658 99840.3 68.7844 7171.53 1
2024-05-14T13:05:03+0100 20.8979 99838.6 68.7759 7162.35 1
2024-05-14T13:06:03+0100 20.9208 99843.8 68.6436 7166.93 1
2024-05-14T13:07:03+0100 20.9303 99845.4 68.747 7144.05 1
2024-05-14T13:08:03+0100 20.9249 99846 68.7122 7139.49 0
2024-05-14T13:09:04+0100 20.9036 99845.2 68.7224 7157.76 1
2024-05-14T13:10:04+0100 20.8737 99850.5 68.575 7144.05 1
2024-05-14T13:11:04+0100 20.8753 99850.6 68.8879 7139.49 1
2024-05-14T13:12:04+0100 20.9152 99849.3 68.8602 7134.94 1
```
If last field is not 1 then the measurement, at least for gas resistance, cannot be trusted.
```sh
sed -n '/1$/p' log.txt > test.txt
```
Then graph with gnuplot
```
# gnuplot
reset
set key autotitle columnhead
set terminal pngcairo enhanced size 2*1920/3,2*1080/3
set grid
set xdata time
set timefmt "%Y-%m-%dT%H:%M:%S%z"
# gas res vs time
set title "[I_{dac}=100, 100ms, target=300 C] GasRes over time"
set xlabel "Time"
set ylabel "Gas Resistance (OHM)"
set output "gas.png"
plot 'test.txt' u 1:5 w p pt 3 ps 1 t "BME680"
set title "[I_{dac}=100, 100ms, target=300 C] Temperature over time"
set xlabel "Time"
set ylabel "Temperature (C)"
set output "temp.png"
plot 'test.txt' u 1:2 w p pt 3 ps 1 t "BME680"
set title "[I_{dac}=100, 100ms, target=300 C] Pressure over time"
set xlabel "Time"
set ylabel "Pressure (Pa)"
set output "press.png"
plot 'test.txt' u 1:3 w p pt 3 ps 1 t "BME680"
set title "[I_{dac}=100, 100ms, target=300 C] Humidity over time"
set xlabel "Time"
set ylabel "Humidity (%RH)"
set output "hum.png"
plot 'test.txt' u 1:4 w p pt 3 ps 1 t "BME680"
```

14
example/README.md
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@ -1,6 +1,20 @@
# bme680/example
log.c
```
2024-05-14T13:03:02+0100 20.8916 99836.7 68.6594 7180.73 1
2024-05-14T13:04:03+0100 20.8658 99840.3 68.7844 7171.53 1
2024-05-14T13:05:03+0100 20.8979 99838.6 68.7759 7162.35 1
2024-05-14T13:06:03+0100 20.9208 99843.8 68.6436 7166.93 1
2024-05-14T13:07:03+0100 20.9303 99845.4 68.747 7144.05 1
2024-05-14T13:08:03+0100 20.9249 99846 68.7122 7139.49 0
2024-05-14T13:09:04+0100 20.9036 99845.2 68.7224 7157.76 1
2024-05-14T13:10:04+0100 20.8737 99850.5 68.575 7144.05 1
2024-05-14T13:11:04+0100 20.8753 99850.6 68.8879 7139.49 1
2024-05-14T13:12:04+0100 20.9152 99849.3 68.8602 7134.94 1
```
iterate\_setpoint.c
```
heater_target=300.0, ambient_temp=19.0

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example/log.c Normal file
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#define _DEFAULT_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include "bme680.h"
#include "i2c.h"
#define AMBIENT_TEMP_GUESS 19.0
#define HEATER_TARGET 300.0
int main(void) {
bme680_t bme680;
uint8_t mode;
double temperature = AMBIENT_TEMP_GUESS;
time_t curr_time;
char date[100];
bme680.dev.init = i2c_init;
bme680.dev.read = i2c_read;
bme680.dev.write = i2c_write;
bme680.dev.deinit = i2c_deinit;
bme680.dev.sleep = usleep;
mode = BME680_MODE_FLOAT | BME680_I2C | BME680_ENABLE_GAS;
if (bme680_init(&bme680, mode) != 0) {
fprintf(stderr, "bme680_init()\n");
exit(EXIT_FAILURE);
}
START:
bme680_reset(&bme680);
if (bme680_calibrate(&bme680) != 0) {
fprintf(stderr, "bme680_calibrate()\n");
bme680_deinit(&bme680);
exit(EXIT_FAILURE);
}
bme680.cfg.osrs_t = BME680_OVERSAMPLE_X16;
bme680.cfg.osrs_p = BME680_OVERSAMPLE_X16;
bme680.cfg.osrs_h = BME680_OVERSAMPLE_X8;
bme680.cfg.filter = BME680_IIR_COEFF_127;
bme680.cfg.res_heat[0] = bme680_calc_target(&bme680, HEATER_TARGET, temperature);
bme680.cfg.idac_heat[0] = BME680_IDAC(100);
bme680.cfg.gas_wait[0] = BME680_GAS_WAIT(25, BME680_GAS_WAIT_X4);
bme680.setpoint = 0;
if (bme680_configure(&bme680) != 0) {
fprintf(stderr, "bme680_configure()\n");
bme680_deinit(&bme680);
exit(EXIT_FAILURE);
}
if (bme680_start(&bme680) != 0) {
fprintf(stderr, "bme680_start()\n");
bme680_deinit(&bme680);
exit(EXIT_FAILURE);
}
if (bme680_poll(&bme680) != 0) {
fprintf(stderr, "bme680_poll()\n");
bme680_deinit(&bme680);
exit(EXIT_FAILURE);
}
if (bme680_read(&bme680) != 0) {
fprintf(stderr, "bme680_read()\n");
bme680_deinit(&bme680);
exit(EXIT_FAILURE);
}
curr_time = time(NULL);
strftime(date, 100, "%FT%T%z", localtime(&curr_time));
printf("%s %g %g %g %g %d\n",
date,
bme680.fcomp.temp,
bme680.fcomp.press,
bme680.fcomp.hum,
bme680.fcomp.gas_res,
!!bme680.heat_stab);
temperature = bme680.fcomp.temp;
// 60 secs
usleep(1000*1000*60);
goto START;
bme680_deinit(&bme680);
return 0;
}