0.3.2 HX711_MP

Author: RobTillaart

libraries/HX711_MP/CHANGELOG..md

@@ -5,6 +5,11 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 
+## [0.3.2] - 2025-06-19
+- fix **is_ready()** (see HX711 #65)
+- add **last_time_read()** to replace **last_read()**
+- minor edits
+
 ## [0.3.1] - 2024-11-08
 - fix #7, sync with HX711 0.5.1
 - clean up examples a bit

libraries/HX711_MP/HX711_MP.cpp

@@ -1,7 +1,7 @@
 //
 //    FILE: HX711_MP.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.3.1
+// VERSION: 0.3.2
 // PURPOSE: Library for load cells for UNO
 //     URL: https://github.com/RobTillaart/HX711_MP
 //     URL: https://github.com/RobTillaart/HX711
@@ -22,7 +22,7 @@ HX711_MP::HX711_MP(uint8_t size)
     _size = 2;   //  hard coded minimum!!
   }
   _gain     = HX711_CHANNEL_A_GAIN_128;
-  _lastRead = 0;
+  _lastTimeRead = 0;
   _mode     = HX711_AVERAGE_MODE;
 }
 
@@ -38,7 +38,7 @@ void HX711_MP::begin(uint8_t dataPin, uint8_t clockPin, bool fastProcessor )
   _clockPin = clockPin;
   _fastProcessor = fastProcessor;
 
-  pinMode(_dataPin, INPUT);
+  pinMode(_dataPin, INPUT_PULLUP);
   pinMode(_clockPin, OUTPUT);
   digitalWrite(_clockPin, LOW);
 
@@ -51,7 +51,7 @@ void HX711_MP::reset()
   power_down();
   power_up();
   _gain     = HX711_CHANNEL_A_GAIN_128;
-  _lastRead = 0;
+  _lastTimeRead = 0;
   _mode     = HX711_AVERAGE_MODE;
 }
 
@@ -143,13 +143,13 @@ float HX711_MP::read()
 
   while (m > 0)
   {
-    //  delayMicroSeconds(1) needed for fast processors?
+    //  delayMicroSeconds(1) is needed for fast processors
+    //  T2  >= 0.2 us
     digitalWrite(_clockPin, HIGH);
-    if (_fastProcessor)
-        delayMicroseconds(1);
+    if (_fastProcessor) delayMicroseconds(1);
     digitalWrite(_clockPin, LOW);
-    if (_fastProcessor)
-        delayMicroseconds(1);
+    //  keep duty cycle ~50%
+    if (_fastProcessor) delayMicroseconds(1);
     m--;
   }
 
@@ -159,7 +159,7 @@ float HX711_MP::read()
   //  SIGN extend
   if (v.data[2] & 0x80) v.data[3] = 0xFF;
 
-  _lastRead = millis();
+  _lastTimeRead = millis();
   return 1.0 * v.value;
 }
 
@@ -302,7 +302,8 @@ float HX711_MP::get_value(uint8_t times)
 
 float HX711_MP::get_units(uint8_t times)
 {
-  return _multiMap(get_value(times));
+  float units = _multiMap(get_value(times));
+  return units;
 }
 
 
@@ -383,7 +384,7 @@ float HX711_MP::getCalibrateWeight(uint8_t index)
 //
 void HX711_MP::power_down()
 {
-  // at least 60 us HIGH
+  //  at least 60 us HIGH
   digitalWrite(_clockPin, HIGH);
   delayMicroseconds(64);
 }
@@ -399,9 +400,15 @@ void HX711_MP::power_up()
 //
 //  MISC
 //
+uint32_t HX711_MP::last_time_read()
+{
+  return _lastTimeRead;
+}
+
+//  obsolete future
 uint32_t HX711_MP::last_read()
 {
-  return _lastRead;
+  return _lastTimeRead;
 }
 
 
@@ -440,15 +447,15 @@ uint8_t HX711_MP::_shiftIn()
   while (mask > 0)
   {
     digitalWrite(clk, HIGH);
-    if(_fastProcessor)       //  T2  >= 0.2 us
-      delayMicroseconds(1);
+    //  T2  >= 0.2 us
+    if(_fastProcessor) delayMicroseconds(1);
     if (digitalRead(data) == HIGH)
     {
       value |= mask;
     }
     digitalWrite(clk, LOW);
-    if(_fastProcessor)
-      delayMicroseconds(1);   //  keep duty cycle ~50%
+    //  keep duty cycle ~50%
+    if(_fastProcessor) delayMicroseconds(1);
     mask >>= 1;
   }
   return value;

libraries/HX711_MP/HX711_MP.h

@@ -2,7 +2,7 @@
 //
 //    FILE: HX711_MP.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.3.1
+// VERSION: 0.3.2
 // PURPOSE: Library for load cells for Arduino
 //     URL: https://github.com/RobTillaart/HX711_MP
 //     URL: https://github.com/RobTillaart/HX711
@@ -15,7 +15,7 @@
 
 #include "Arduino.h"
 
-#define HX711_MP_LIB_VERSION               (F("0.3.1"))
+#define HX711_MP_LIB_VERSION               (F("0.3.2"))
 
 
 const uint8_t HX711_AVERAGE_MODE = 0x00;
@@ -160,6 +160,9 @@ class HX711_MP
 
 
   //  TIME OF LAST READ
+  uint32_t last_time_read();
+  //  obsolete in the future
+  [[deprecated("Use last_time_read() instead.")]]
   uint32_t last_read();
 
 
@@ -178,7 +181,7 @@ class HX711_MP
   uint8_t  _clockPin;
 
   uint8_t  _gain;
-  uint32_t _lastRead;
+  uint32_t _lastTimeRead;
   uint8_t  _mode;
   bool     _fastProcessor;
 

libraries/HX711_MP/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2019-2024 Rob Tillaart
+Copyright (c) 2019-2025 Rob Tillaart
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

libraries/HX711_MP/README.md

@@ -48,21 +48,37 @@ This library does not provide means to control the **RATE** yet.
 If there is a need (issue) I will implement this in the library.
 For now one can add an IOpin for this and use **digitalWrite()**.
 
+If you need more SPS you could consider using the HX71708 device.
+This is a close "relative" of the HX711 that allows to set the SPS to 
+10, 20, 80, or 320 Hz. 
+- https://github.com/beniseman/HX71708 
+
 
 ### Related
 
 - https://github.com/bogde/HX711
 - https://github.com/RobTillaart/weight  (conversions kg <> stone etc.)
+- https://github.com/RobTillaart/HX710AB
 - https://github.com/RobTillaart/HX711
 - https://github.com/RobTillaart/HX711_MP  multipoint calibration version.
 
+Discussion about resolution of the ADC
+- https://forum.arduino.cc/t/scale-from-50-kg-to-5000kg-what-adc/1139710
+
+Support for the HX71708 device (close related)
+- https://github.com/beniseman/HX71708 allows to set the SPS to 10, 20, 80, or 320 Hz
+
+Load cells go to very high weights, this side sells them up to 200 ton.
+Never seen one and cannot tell if it will work with this library.
+- https://stekon.nl/load-cells
+
 
 ### Faulty boards
 
 - https://forum.arduino.cc/t/load-cell-amplifier-hx711-wrong-ground/1046075
 
 
-#### Differences HX711
+### Differences HX711
 
 Although the library is derived from the HX711 library they are not compatible.
 Almost is the right word here.
@@ -97,19 +113,25 @@ is more math involved for converting raw data to weights.
 Parameter sets the size of for the calibration arrays. 
 Allowed range for size is 2..10.
 - **~HX711_MP()**
-- **void begin(uint8_t dataPin, uint8_t clockPin, bool fastProcessor)** sets a fixed gain 128 for now.
+- **void begin(uint8_t dataPin, uint8_t clockPin, bool fastProcessor = false)** sets a fixed gain 128 for now.
 The fastProcessor option adds a 1 uS delay for each clock half-cycle to keep the time greater than 200 nS.
 - **void reset()** set internal state to start condition.
 Reset also does a power down / up cycle.
 It does not reset the calibration data.
 
 
-### Read
+### isReady
+
+Different ways to wait for a new measurement.
 
 - **bool is_ready()** checks if load cell is ready to read.
 - **void wait_ready(uint32_t ms = 0)** wait until ready, check every ms.
 - **bool wait_ready_retry(uint8_t retries = 3, uint32_t ms = 0)** wait max retries.
 - **bool wait_ready_timeout(uint32_t timeout = 1000, uint32_t ms = 0)** wait max timeout milliseconds.
+
+
+### Read
+
 - **float read()** raw read.
 - **float read_average(uint8_t times = 10)** get average of times raw reads. times = 1 or more.
 - **float read_median(uint8_t times = 7)** get median of multiple raw reads. 

libraries/HX711_MP/examples/HX_MP_calibrate/HX_MP_calibrate.ino

@@ -24,6 +24,7 @@ float f;
 void setup()
 {
   Serial.begin(115200);
+  Serial.println();
   Serial.println(__FILE__);
   Serial.print("HX711_MP_LIB_VERSION: ");
   Serial.println(HX711_MP_LIB_VERSION);

libraries/HX711_MP/examples/HX_MP_performance/HX_MP_performance.ino

@@ -24,6 +24,7 @@ volatile float f;
 void setup()
 {
   Serial.begin(115200);
+  Serial.println();
   Serial.println(__FILE__);
   Serial.print("HX711_MP_LIB_VERSION: ");
   Serial.println(HX711_MP_LIB_VERSION);

libraries/HX711_MP/examples/HX_MP_performance2/HX_MP_performance2.ino

@@ -24,6 +24,7 @@ volatile float f;
 void setup()
 {
   Serial.begin(115200);
+  Serial.println();
   Serial.println(__FILE__);
   Serial.print("HX711_MP_LIB_VERSION: ");
   Serial.println(HX711_MP_LIB_VERSION);

libraries/HX711_MP/examples/HX_MP_plotter/HX_MP_plotter.ino

@@ -24,6 +24,7 @@ float f;
 void setup()
 {
   Serial.begin(115200);
+  // Serial.println();
   // Serial.println(__FILE__);
   // Serial.print("HX711_MP_LIB_VERSION: ");
   // Serial.println(HX711_MP_LIB_VERSION);

libraries/HX711_MP/examples/HX_MP_runtime_calibration/HX_MP_runtime_calibration.ino

@@ -24,6 +24,7 @@ uint8_t PIN_DOWN = 19;
 void setup()
 {
   Serial.begin(115200);
+  Serial.println();
   Serial.println(__FILE__);
   Serial.print("HX711_MP_LIB_VERSION: ");
   Serial.println(HX711_MP_LIB_VERSION);