Report raw value from HX711 to overcome auto-tare functionality.

Currently, when the device is switched off (intentionally or due to
power cut), Tasmota only supports starting with the last known weight
(Sensor34 7) or starting with 0 kg. In either case, this is sometimes
not the desired functionality. For off-site logging of weights, it is
more useful to report the raw, absolute value from the HX711 and to do
calibration/tare in upper layers.

Note: although it is called "Raw" value, the value is both averaged
and scaled! It is just the offset compensation that is missing.
This commit is contained in:
Thomas Herrmann 2019-12-10 10:55:46 +01:00
parent 3d2e77f320
commit b9545f5194
1 changed files with 11 additions and 3 deletions

View File

@ -57,6 +57,7 @@
#define D_JSON_WEIGHT_MAX "WeightMax"
#define D_JSON_WEIGHT_ITEM "WeightItem"
#define D_JSON_WEIGHT_CHANGE "WeightChange"
#define D_JSON_WEIGHT_RAW "WeightRaw"
enum HxCalibrationSteps { HX_CAL_END, HX_CAL_LIMBO, HX_CAL_FINISH, HX_CAL_FAIL, HX_CAL_DONE, HX_CAL_FIRST, HX_CAL_RESET, HX_CAL_START };
@ -64,8 +65,10 @@ const char kHxCalibrationStates[] PROGMEM = D_HX_CAL_FAIL "|" D_HX_CAL_DONE "|"
struct HX {
long weight = 0;
long raw = 0;
long last_weight = 0;
long sum_weight = 0;
long sum_raw = 0;
long offset = 0;
long scale = 1;
long weight_diff = 0;
@ -272,13 +275,17 @@ void HxInit(void)
void HxEvery100mSecond(void)
{
Hx.sum_weight += HxRead();
long raw = HxRead();
Hx.sum_raw += raw;
Hx.sum_weight += raw;
Hx.sample_count++;
if (HX_SAMPLES == Hx.sample_count) {
long average = Hx.sum_weight / Hx.sample_count; // grams
long raw_average = Hx.sum_raw / Hx.sample_count; // grams
long value = average - Hx.offset; // grams
Hx.weight = value / Hx.scale; // grams
Hx.raw = raw_average / Hx.scale;
if (Hx.weight < 0) {
if (Settings.energy_frequency_calibration) {
long difference = Settings.energy_frequency_calibration + Hx.weight;
@ -367,6 +374,7 @@ void HxEvery100mSecond(void)
}
Hx.sum_weight = 0;
Hx.sum_raw = 0;
Hx.sample_count = 0;
}
}
@ -405,7 +413,7 @@ void HxShow(bool json)
dtostrfd(weight, Settings.flag2.weight_resolution, weight_chr);
if (json) {
ResponseAppend_P(PSTR(",\"HX711\":{\"" D_JSON_WEIGHT "\":%s%s}"), weight_chr, scount);
ResponseAppend_P(PSTR(",\"HX711\":{\"" D_JSON_WEIGHT "\":%s%s, \"" D_JSON_WEIGHT_RAW "\":%d}"), weight_chr, scount, Hx.raw);
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_HX711_WEIGHT, weight_chr);
@ -565,4 +573,4 @@ bool Xsns34(uint8_t function)
return result;
}
#endif // USE_HX711
#endif // USE_HX711