Prel code for formula creation

2022-01-03 18:30:57 +01:00 · 2022-01-03 18:30:57 +01:00 · d075fe2117
commit d075fe2117
parent 48f71bd59a
26 changed files with 626 additions and 61 deletions
--- a/README.md
+++ b/README.md
@ -7,6 +7,7 @@ I started this project out of curiosity for how a motion sensor is working and s
 After 6 months of testing I believe this is working as planned. It give accurate readings same as the orginal iSpindel software. 

 Version history
+* v0.5 Added support for creating formula on device + bug fixes.
 * v0.4 First official version with 5+ brews on record. 

 Lower priority
@ -127,11 +128,19 @@ http://192.168.1.1/firmware/gravmon/

 Contents version.json
 ```
-{ "project":"gravmon", "version":"0.3.0" }
+{ "project":"gravmon", "version":"0.5.0" }
 ```

 ![Config - Hardware](img/config4.png)

+### Calibration page
+
+http://gravmon.local/calibration.htm
+
+The device page is used to enter gravity + angle/tilt into the device in order to create a formula. Data will be saved on the device and a formula will be checked against the entered numbers for accuracy. Support currently up to 5 values and the more readings the more accurate the formula will be. Its prefeered to use at least 3 values. 
+
+![Device](img/calibration.png)
+
 # Building a device

 See the iSpindle documentation for building a device. 
--- a/html/calibration.htm
+++ b/html/calibration.htm
@ -0,0 +1,243 @@
+<!doctype html>
+<html lang="en">
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+  <meta name="description" content="">
+  <title>Beer Gravity Monitor</title>
+  <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet" crossorigin="anonymous">
+  <script src="https://code.jquery.com/jquery-3.6.0.min.js" integrity="sha256-/xUj+3OJU5yExlq6GSYGSHk7tPXikynS7ogEvDej/m4=" crossorigin="anonymous"></script>
+  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js" crossorigin="anonymous"></script>
+</head> 
+<body class="py-4">
+
+<!-- START MENU -->
+
+<nav class="navbar navbar-expand-sm navbar-dark bg-primary">
+
+  <a class="navbar-brand" href="/index.htm">Beer Gravity Monitor</a>
+  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbar" aria-controls="navbar" aria-expanded="false" aria-label="Toggle navigation">
+    <span class="navbar-toggler-icon"></span>
+  </button>
+  
+  <div class="collapse navbar-collapse" id="navbar"> 
+    <ul class="navbar-nav mr-auto">
+      <li class="nav-item">
+        <a class="nav-link" href="/index.htm">Home <span class="sr-only">(current)</span></a>
+      </li>
+      <li class="nav-item">
+        <a class="nav-link" href="/device.htm">Device</a>
+      </li>
+      <li class="nav-item">
+        <a class="nav-link" href="/config.htm">Configuration</a>
+      </li>
+      <li class="nav-item active">
+        <a class="nav-link" href="/calibration.htm">Calibration</a>
+      </li>
+      <li class="nav-item">
+        <a class="nav-link" href="/about.htm">About</a>
+      </li>
+    </ul>
+  </div>
+  <div class="spinner-border text-light" id="spinner" role="status"></div>
+</nav>
+
+<!-- START MAIN INDEX -->
+
+<div class="container">
+
+  <hr class="my-2">
+
+  <div class="alert alert-success alert-dismissible fade hide show d-none" role="alert" id="alert">
+    <div id="alert-msg">...</div>
+    <button type="button" id="alert-btn" class="close" aria-label="Close">
+      <span aria-hidden="true">&times;</span>
+    </button>
+  </div>
+
+  <script type="text/javascript">
+    function showError( msg ) {
+      $('.alert').removeClass('alert-success').addClass('alert-danger').removeClass('d-none').addClass('show')
+      $('#alert-msg').text( msg );
+    }
+
+    function showSuccess( msg ) {
+      $('.alert').addClass('alert-success').removeClass('alert-danger').removeClass('d-none').addClass('show')
+      $('#alert-msg').text( msg );
+    }
+
+    $("#alert-btn").click(function(e){
+      $('.alert').addClass('d-none').removeClass('show')
+    });    
+  </script>
+
+  <div class="accordion" id="accordion">
+
+    <div class="card">
+      <div class="card-header" id="headingOne">
+        <h2 class="mb-0">
+          <button class="btn btn-link btn-block text-left" type="button" data-toggle="collapse" data-target="#collapseOne" aria-expanded="true" aria-controls="collapseOne">
+            Formula calculation
+          </button>
+        </h2>
+      </div>  
+
+      <div id="collapseOne" class="collapse show" aria-labelledby="headingOne" data-parent="#accordion">
+        <div class="card-body">
+          <form action="/api/formula" method="post">
+            <input type="text" name="id" id="id" hidden>
+
+            <div class="row mb-3">
+                Here you can create your gravity formula by entering angles and the corresponding gravity (SG). These values
+                will be saved for future use. Angles with 0 (zero) will be skipped. The values below will be used to check the 
+                formula and if the deviation is more than 1.5 SG then the forumla will be rejected.
+            </div>
+
+            <div class="form-group row">
+              <label class="col-sm-2 col-form-label">#:</label>
+              <label class="col-sm-4 col-form-label">Angle:</label>
+              <label class="col-sm-4 col-form-label">Gravity (SG):</label>
+            </div>
+
+            <div class="form-group row">
+              <label for="angle1" class="col-sm-2 col-form-label">1.</label>
+              <div class="col-sm-4">
+                <input type="number"  min="0" max="90" step="0.001" class="form-control" name="a1" id="a1">
+              </div>
+              <div class="col-sm-4">
+                <input type="number"  min="1" max="2" step="0.0001" class="form-control" name="g1" id="g1">
+              </div>
+            </div>
+
+            <div class="form-group row">
+              <label for="angle2" class="col-sm-2 col-form-label">2.</label>
+              <div class="col-sm-4">
+                <input type="number"  min="0" max="90" step="0.001" class="form-control" name="a2" id="a2">
+              </div>
+              <div class="col-sm-4">
+                <input type="number"  min="1" max="2" step="0.0001" class="form-control" name="g2" id="g2">
+              </div>
+            </div>
+
+            <div class="form-group row">
+              <label for="angle3" class="col-sm-2 col-form-label">3.</label>
+              <div class="col-sm-4">
+                <input type="number"  min="0" max="90" step="0.001" class="form-control" name="a3" id="a3">
+              </div>
+              <div class="col-sm-4">
+                <input type="number"  min="1" max="2" step="0.0001" class="form-control" name="g3" id="g3">
+              </div>
+            </div>
+
+            <div class="form-group row">
+              <label for="angle4" class="col-sm-2 col-form-label">4.</label>
+              <div class="col-sm-4">
+                <input type="number"  min="0" max="90" step="0.001" class="form-control" name="a4" id="a4">
+              </div>
+              <div class="col-sm-4">
+                <input type="number"  min="1" max="2" step="0.0001" class="form-control" name="g4" id="g4">
+              </div>
+            </div>
+
+            <div class="form-group row">
+              <label for="angle5" class="col-sm-2 col-form-label">5.</label>
+              <div class="col-sm-4">
+                <input type="number"  min="0" max="90" step="0.001" class="form-control" name="a5" id="a5">
+              </div>
+              <div class="col-sm-4">
+                <input type="number"  min="1" max="2" step="0.0001" class="form-control" name="g5" id="g5">
+              </div>
+            </div>
+
+            <div class="form-group row">
+              <div class="col-sm-8 offset-sm-0">
+                <button type="submit" class="btn btn-primary" id="calculate-btn">Save & Calculate</button>
+              </div>
+            </div>
+
+            <div class="form-group row">
+              <label for="calculate-btn" class="col-sm-2 col-form-label">Current angle: </label>
+              <label for="calculate-btn" class="col-sm-2 col-form-label" id="angle"></label>
+            </div>
+            <div class="form-group row">
+                <label for="calculate-btn" class="col-sm-2 col-form-label">Formula: </label>
+              <label for="calculate-btn" class="col-sm-8 col-form-label" id="formula">Loading...</label>
+            </div>
+
+          </form>
+        </div>
+      </div>
+    </div>
+  </div>
+  <hr class="my-4">
+</div>
+
+<script type="text/javascript">
+  g1.onchange = setFourNumberDecimal
+  g2.onchange = setFourNumberDecimal
+  g3.onchange = setFourNumberDecimal
+  g4.onchange = setFourNumberDecimal
+  g5.onchange = setFourNumberDecimal
+
+  a1.onchange = setTwoNumberDecimal
+  a2.onchange = setTwoNumberDecimal
+  a3.onchange = setTwoNumberDecimal
+  a4.onchange = setTwoNumberDecimal
+  a5.onchange = setTwoNumberDecimal
+
+  window.onload = getConfig;
+  setButtonDisabled( true );
+
+  function setTwoNumberDecimal(event) {
+    this.value = parseFloat(this.value).toFixed(2);
+  } 
+
+  function setFourNumberDecimal(event) {
+    this.value = parseFloat(this.value).toFixed(4);
+  } 
+
+  function setButtonDisabled( b ) {
+    $("#calculate-btn").prop("disabled", b);
+  }
+
+  // Get the configuration values from the API
+  function getConfig() {
+    setButtonDisabled( true );
+
+    var url = "/api/formula";
+    //var url = "/test/formula.json";
+    $('#spinner').show(); 
+    $.getJSON(url, function (cfg) {
+      console.log( cfg );
+     
+      $("#id").val(cfg["id"]);
+      $("#angle").text(cfg["angle"]);
+      $("#formula").text(cfg["gravity-formula"]);
+
+      $("#a1").val( parseFloat(cfg["a1"]).toFixed(2) );
+      $("#a2").val( parseFloat(cfg["a2"]).toFixed(2) );
+      $("#a3").val( parseFloat(cfg["a3"]).toFixed(2) );
+      $("#a4").val( parseFloat(cfg["a4"]).toFixed(2) );
+      $("#a5").val( parseFloat(cfg["a5"]).toFixed(2) );
+
+      $("#g1").val( parseFloat(cfg["g1"]).toFixed(4) );
+      $("#g2").val( parseFloat(cfg["g2"]).toFixed(4) );
+      $("#g3").val( parseFloat(cfg["g3"]).toFixed(4) );
+      $("#g4").val( parseFloat(cfg["g4"]).toFixed(4) );
+      $("#g5").val( parseFloat(cfg["g5"]).toFixed(4) );
+    })
+    .fail(function () {
+      showError('Unable to get data from the device.');
+    })
+    .always(function() {
+      $('#spinner').hide(); 
+      setButtonDisabled( false );
+    });
+  }
+</script>
+
+<!-- START FOOTER -->
+
+<div class="container-fluid themed-container bg-primary text-light">(C) Copyright 2021-22 Magnus Persson</div>
+</body>
+</html>
--- a/html/calibration.min.htm
+++ b/html/calibration.min.htm
--- a/img/config1.png
+++ b/img/config1.png
--- a/img/config2.png
+++ b/img/config2.png
--- a/img/config3.png
+++ b/img/config3.png
--- a/img/config4.png
+++ b/img/config4.png
--- a/img/device.png
+++ b/img/device.png
--- a/img/index.png
+++ b/img/index.png
--- a/platformio.ini
+++ b/platformio.ini
@ -15,12 +15,13 @@ include_dir = lib
 [common_env_data]
 upload_speed = 921600
 monitor_speed =  115200
-platform = espressif8266
+#platform = espressif8266 @ 2.6.3
+platform = espressif8266 @ 3.2.0
 framework = arduino
 board = d1_mini
 build_unflags = 
-0src_build_flags = -Wunused-variable -Wregister -Wchar-subscripts
-build_flags = #-O0 -Wl,-Map,output.map
+#src_build_flags = -Wunused-variable -Wregister -Wchar-subscripts
+build_flags = 
 	-D BAUD=${common_env_data.monitor_speed}
 	-D ACTIVATE_OTA	
 	#-D USE_GYRO_TEMP			 # If this is enabled the DS18 will not be used, temp is read from the gyro.  
@ -30,21 +31,22 @@ build_flags = #-O0 -Wl,-Map,output.map
 	#-D SKIP_SLEEPMODE
 	#-D DOUBLERESETDETECTOR_DEBUG true
 	-D USE_LITTLEFS=true
-	-D EMBED_HTML			      # If this is not used the html files needs to be on the file system (can be uploaded)
+	-D EMBED_HTML			     				# If this is not used the html files needs to be on the file system (can be uploaded)
 	-D USER_SSID=\""\""           # =\""myssid\""
 	-D USER_SSID_PWD=\""\""       # =\""mypwd\""	
 	-D CFG_APPVER="\"0.4.0\""
 lib_deps = # Switched to forks for better version control.
 	# Using local copy of this library
-  #https://github.com/mp-se/i2cdevlib																	#	https://github.com/jrowberg/i2cdevlib.git 		
-	https://github.com/mp-se/tinyexpr																		#	https://github.com/codeplea/tinyexpr
-	https://github.com/mp-se/incbin																			#	https://github.com/graphitemaster/incbin
-	https://github.com/mp-se/ESP_DoubleResetDetector										# https://github.com/khoih-prog/ESP_DoubleResetDetector
-	https://github.com/mp-se/WiFiManager																# https://github.com/tzapu/WiFiManager
-	https://github.com/mp-se/Arduino-Log																# https://github.com/thijse/Arduino-Log
-	https://github.com/mp-se/ArduinoJson																# https://github.com/bblanchon/ArduinoJson
-	https://github.com/mp-se/OneWire																		# https://github.com/PaulStoffregen/OneWire
-	https://github.com/mp-se/Arduino-Temperature-Control-Library				# https://github.com/milesburton/Arduino-Temperature-Control-Library
+  #https://github.com/mp-se/i2cdevlib																	  #	https://github.com/jrowberg/i2cdevlib.git 		
+	https://github.com/mp-se/tinyexpr																		  #	https://github.com/codeplea/tinyexpr
+	https://github.com/mp-se/incbin																			  #	https://github.com/graphitemaster/incbin
+	https://github.com/mp-se/ESP_DoubleResetDetector#v1.2.1   						# https://github.com/khoih-prog/ESP_DoubleResetDetector
+	https://github.com/mp-se/WiFiManager#2.0.5-beta 										  # https://github.com/tzapu/WiFiManager
+	https://github.com/mp-se/Arduino-Log#1.1.1    												# https://github.com/thijse/Arduino-Log
+	https://github.com/mp-se/ArduinoJson#v6.18.5 											   	# https://github.com/bblanchon/ArduinoJson
+	https://github.com/mp-se/OneWire#v2.3.6  												   		# https://github.com/PaulStoffregen/OneWire
+	https://github.com/mp-se/Arduino-Temperature-Control-Library#3.9.1  	# https://github.com/milesburton/Arduino-Temperature-Control-Library
+	https://github.com/mp-se/arduinoCurveFitting#v1.0.6      							# https://github.com/Rotario/arduinoCurveFitting

 [env:gravity-debug]
 upload_speed = ${common_env_data.upload_speed}
@ -52,18 +54,23 @@ monitor_speed = ${common_env_data.monitor_speed}
 framework = ${common_env_data.framework}
 platform = ${common_env_data.platform}
 extra_scripts =  
+	script/copy_html.py
 	script/copy_firmware.py
 	script/create_versionjson.py
-build_unflags = ${common_env_data.build_unflags}
+build_unflags = 
+	${common_env_data.build_unflags}
 build_flags = 
-    ${common_env_data.build_flags}
-	-D COLLECT_PERFDATA				# This option will collect runtime data for a few defined methods to measure time, dumped to serial and/or influxdb 
-	-D LOG_LEVEL=6					# Maximum log level for the debug build.
+	-D PIO_FRAMEWORK_ARDUINO_ENABLE_EXCEPTIONS
+	#-D DEACTIVATE_SLEEPMODE
+  ${common_env_data.build_flags}
+	-D COLLECT_PERFDATA														# This option will collect runtime data for a few defined methods to measure time, dumped to serial and/or influxdb 
+	-D LOG_LEVEL=6																# Maximum log level for the debug build.
 lib_deps = 
 	${common_env_data.lib_deps}
 board = ${common_env_data.board}
 build_type = debug
 board_build.filesystem = littlefs
+monitor_filters = esp8266_exception_decoder

 [env:gravity-release]
 upload_speed = ${common_env_data.upload_speed}
@ -71,6 +78,7 @@ monitor_speed = ${common_env_data.monitor_speed}
 framework = ${common_env_data.framework}
 platform = ${common_env_data.platform}
 extra_scripts =  
+	script/copy_html.py
 	script/copy_firmware.py
 	script/create_versionjson.py
 build_unflags = ${common_env_data.build_unflags}
@ -89,6 +97,7 @@ monitor_speed = ${common_env_data.monitor_speed}
 framework = ${common_env_data.framework}
 platform = ${common_env_data.platform}
 extra_scripts =  
+	script/copy_html.py
 	script/copy_firmware.py
 	script/create_versionjson.py
 build_unflags = ${common_env_data.build_unflags}
--- a/script/copy_html.py
+++ b/script/copy_html.py
@ -5,25 +5,25 @@ print( "Executing custom step " )
 dir    = env.GetLaunchDir()
 source = dir + "/html/"
 target = dir + "/data/"
-print( "Copy file : " + source + " -> " + target )
+print( "Copy html-files from " + source + " -> " + target )

 file = "about.min.htm"
-print( "Copy file: " + source + file + "->" + target + file)
+#print( "Copy file: " + source + file + "->" + target + file)
 shutil.copyfile( source + file, target + file )
 file = "calibration.min.htm"
-print( "Copy file: " + source + file + "->" + target + file)
+#print( "Copy file: " + source + file + "->" + target + file)
 shutil.copyfile( source + file, target + file )
 file = "config.min.htm"
-print( "Copy file: " + source + file + "->" + target + file)
+#print( "Copy file: " + source + file + "->" + target + file)
 shutil.copyfile( source + file, target + file )
 file = "device.min.htm"
-print( "Copy file: " + source + file + "->" + target + file)
+#print( "Copy file: " + source + file + "->" + target + file)
 shutil.copyfile( source + file, target + file )
 file = "index.min.htm"
-print( "Copy file: " + source + file + "->" + target + file)
+#print( "Copy file: " + source + file + "->" + target + file)
 shutil.copyfile( source + file, target + file )
 file = "upload.min.htm"
-print( "Copy file: " + source + file + "->" + target + file)
+#print( "Copy file: " + source + file + "->" + target + file)
 shutil.copyfile( source + file, target + file )

 #print( "Adding custom build step (copy ./heml/*.min.html to ./data/): ")
--- a/script/create_versionjson.py
+++ b/script/create_versionjson.py
@ -36,6 +36,12 @@ def after_build(source, target, env):
    print( "Copy file : " + source + " -> " + target )
    shutil.copyfile( source, target )

+    # Copy file 4
+    source = dir + "\\data\\calibration.min.htm"
+    target = dir + "\\bin\\calibration.min.htm"
+    print( "Copy file : " + source + " -> " + target )
+    shutil.copyfile( source, target )
+
    target = dir + "\\bin\\version.json"
    ver = get_build_flag_value("CFG_APPVER")

--- a/src/calc.cpp
+++ b/src/calc.cpp
@ -24,14 +24,91 @@ SOFTWARE.
 #include "calc.h"
 #include "helper.h"
 #include "config.h"
-#include "tinyexpr.h"
+#include <tinyexpr.h>
 #include "tempsensor.h"
+#include <curveFitting.h>
+
+#define FORMULA_MAX_DEVIATION 1.5
+
+
+//
+// Use values to derive a formula
+//
+int createFormula( RawFormulaData& fd, char *formulaBuffer, int order ) {
+  
+    int noAngles = 0;
+
+    // Check how many valid values we have got
+    if( fd.a[0]>0 && fd.a[1]>0 && fd.a[2]>0 && fd.a[3]>0 && fd.a[4]>0 )
+        noAngles = 5;
+    else if( fd.a[0]>0 && fd.a[1]>0 && fd.a[2]>0 && fd.a[3]>0 )
+        noAngles = 4;
+    else if( fd.a[0]>0 && fd.a[1]>0 && fd.a[2]>0 )
+        noAngles = 3;
+
+#if LOG_LEVEL==6
+    Log.verbose(F("CALC: Trying to create formula using order = %d, found %d angles" CR), order, noAngles);
+#endif
+
+    if( !noAngles ) {
+        Log.error(F("CALC: Not enough values for deriving formula" CR));
+        return ERR_FORMULA_NOTENOUGHVALUES;
+    } else {
+
+        double coeffs[order+1];
+        int ret = fitCurve(order, noAngles, fd.a, fd.g, sizeof(coeffs)/sizeof(double), coeffs);
+
+        //Returned value is 0 if no error
+        if( ret == 0 ) { 
+
+            if( noAngles==5 )
+                sprintf( formulaBuffer, "%.8f*tilt^3+%.8f*tilt^2+%.8f*tilt+%.8f", coeffs[0], coeffs[1], coeffs[2], coeffs[3] );
+            else if( noAngles==4 )
+                sprintf( formulaBuffer, "%.8f*tilt^2+%.8f*tilt+%.8f", coeffs[0], coeffs[1], coeffs[2] );
+            else // ==3
+                sprintf( formulaBuffer, "%.8f*tilt+%.8f", coeffs[0], coeffs[1] );
+
+            bool valid = true;
+
+            for( int i = 0; i < 5; i++ ) {
+                if( fd.a[i]==0 && valid )
+                    break; 
+
+                double g = calculateGravity( fd.a[i], 0, formulaBuffer );
+                double dev = (g-fd.g[i])<0 ? (fd.g[i]-g) : (g-fd.g[i]); 
+
+                // If the deviation is more than 2 degress we mark it as failed.
+                if( dev*1000 > FORMULA_MAX_DEVIATION )
+                    valid = false;
+            }
+      
+            if( !valid ) {
+                Log.error(F("CALC: Deviation to large, formula rejected." CR));
+                return ERR_FORMULA_UNABLETOFFIND;
+            }
+
+            Log.info(F("CALC: Found formula '%s'." CR), formulaBuffer );
+            return 0;
+        } 
+    }
+
+    Log.error(F("CALC: Internal error finding formula." CR));
+    return ERR_FORMULA_INTERNAL;  
+}

 //
 // Calculates gravity according to supplied formula, compatible with iSpindle/Fermentrack formula  
 //
-double calculateGravity( double angle, double temp ) {
+double calculateGravity( double angle, double temp, const char *tempFormula ) {
    const char* formula = myConfig.getGravityFormula();
+
+    if( tempFormula != 0 ) {
+#if LOG_LEVEL==6
+        Log.verbose(F("CALC: Using temporary formula." CR));
+#endif
+        formula = tempFormula;
+    }
+
 #if LOG_LEVEL==6
    Log.verbose(F("CALC: Calculating gravity for angle %F, temp %F." CR), angle, temp);
    Log.verbose(F("CALC: Formula %s." CR), formula);
--- a/src/calc.h
+++ b/src/calc.h
@ -26,10 +26,16 @@ SOFTWARE.

 // Includes
 #include "helper.h"
+#include "config.h"
+
+#define ERR_FORMULA_NOTENOUGHVALUES -1  
+#define ERR_FORMULA_INTERNAL        -2
+#define ERR_FORMULA_UNABLETOFFIND   -3  

 // Functions
-double calculateGravity( double angle, double temp );
+double calculateGravity( double angle, double temp, const char *tempFormula = 0 );
 double gravityTemperatureCorrection( double gravity, double temp, char tempFormat, double calTemp = 20 );
+int createFormula( RawFormulaData& fd, char *formulaBuffer, int order);

 #endif // _CALC_H

--- a/src/config.cpp
+++ b/src/config.cpp
@ -32,11 +32,16 @@ Config myConfig;
 //
 Config::Config() {
    // Assiging default values
-    char buf[20];
+    char buf[30];
    sprintf(&buf[0], "%6x", (unsigned int) ESP.getChipId() );
-    id = &buf[0];
+    id = String( &buf[0] );
    sprintf(&buf[0], "" WIFI_MDNS "%s", getID() );
-    mDNS = &buf[0];
+    mDNS = String( &buf[0] );
+
+#if LOG_LEVEL==6
+    Log.verbose(F("CFG : Created config for %s (%s)." CR), id.c_str(), mDNS.c_str() );
+#endif
+
    setTempFormat('C');
    setGravityFormat('G');
    setSleepInterval(900);             // 15 minutes
@ -44,6 +49,7 @@ Config::Config() {
    setTempSensorAdj(0.0);
    setGravityTempAdj(false);
    gyroCalibration = { 0, 0, 0, 0, 0 ,0 };
+    formulaData = {{ 0, 0, 0, 0, 0},{ 1, 1, 1, 1, 1}};
    saveNeeded = false;
 }

@ -77,6 +83,19 @@ void Config::createJson(DynamicJsonDocument& doc) {
    cal["gx"] = gyroCalibration.gx;
    cal["gy"] = gyroCalibration.gy;
    cal["gz"] = gyroCalibration.gz;
+
+    JsonObject cal2 = doc.createNestedObject( CFG_PARAM_FORMULA_DATA );
+    cal2[ "a1" ] = reduceFloatPrecision( formulaData.a[0], 2);
+    cal2[ "a2" ] = reduceFloatPrecision( formulaData.a[1], 2);
+    cal2[ "a3" ] = reduceFloatPrecision( formulaData.a[2], 2);
+    cal2[ "a4" ] = reduceFloatPrecision( formulaData.a[3], 2);
+    cal2[ "a5" ] = reduceFloatPrecision( formulaData.a[4], 2);
+    
+    cal2[ "g1" ] = reduceFloatPrecision( formulaData.g[0], 4);
+    cal2[ "g2" ] = reduceFloatPrecision( formulaData.g[1], 4);
+    cal2[ "g3" ] = reduceFloatPrecision( formulaData.g[2], 4);
+    cal2[ "g4" ] = reduceFloatPrecision( formulaData.g[3], 4);
+    cal2[ "g5" ] = reduceFloatPrecision( formulaData.g[4], 4);
 }

 //
@ -144,7 +163,7 @@ bool Config::loadFile() {
 #if LOG_LEVEL==6
    serializeJson(doc, Serial);
    Serial.print( CR );
-#endif    
+#endif
    configFile.close();

    if( err ) {
@ -207,6 +226,28 @@ bool Config::loadFile() {
    if( !doc[ CFG_PARAM_GYRO_CALIBRATION ]["gz"].isNull() ) 
        gyroCalibration.gz = doc[ CFG_PARAM_GYRO_CALIBRATION ]["gz"];

+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "a1" ].isNull() ) 
+        formulaData.a[0] = doc[ CFG_PARAM_FORMULA_DATA ][ "a1" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "a2" ].isNull() ) 
+        formulaData.a[1] = doc[ CFG_PARAM_FORMULA_DATA ][ "a2" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "a3" ].isNull() ) 
+        formulaData.a[2] = doc[ CFG_PARAM_FORMULA_DATA ][ "a3" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "a4" ].isNull() ) 
+        formulaData.a[3] = doc[ CFG_PARAM_FORMULA_DATA ][ "a4" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "a5" ].isNull() ) 
+        formulaData.a[4] = doc[ CFG_PARAM_FORMULA_DATA ][ "a5" ].as<double>();
+
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "g1" ].isNull() ) 
+        formulaData.g[0] = doc[ CFG_PARAM_FORMULA_DATA ][ "g1" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "g2" ].isNull() ) 
+        formulaData.g[1] = doc[ CFG_PARAM_FORMULA_DATA ][ "g2" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "g3" ].isNull() ) 
+        formulaData.g[2] = doc[ CFG_PARAM_FORMULA_DATA ][ "g3" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "g4" ].isNull() ) 
+        formulaData.g[3] = doc[ CFG_PARAM_FORMULA_DATA ][ "g4" ].as<double>();
+    if( !doc[ CFG_PARAM_FORMULA_DATA ][ "g5" ].isNull() ) 
+        formulaData.g[4] = doc[ CFG_PARAM_FORMULA_DATA ][ "g5" ];
+
    myConfig.debug();
    saveNeeded = false;     // Reset save flag 
    Log.notice(F("CFG : Configuration file " CFG_FILENAME " loaded." CR));
--- a/src/config.h
+++ b/src/config.h
@ -31,7 +31,7 @@ SOFTWARE.
 #include <stdlib.h>

 // defintions
-#define CFG_JSON_BUFSIZE    2000
+#define CFG_JSON_BUFSIZE    3192

 #define CFG_APPNAME         "GravityMon "       // Name of firmware
 #define CFG_FILENAME        "/gravitymon.json"  // Name of config file
@ -63,6 +63,8 @@ SOFTWARE.
 #define CFG_PARAM_TEMP_ADJ              "temp-adjustment-value"         // Correction value for temp sensor
 #define CFG_PARAM_GYRO_CALIBRATION      "gyro-calibration-data"         // READ ONLY

+#define CFG_PARAM_FORMULA_DATA          "formula-calculation-data"      // Raw data for the formula calculation
+
 // These are used in API's
 #define CFG_PARAM_APP_NAME           "app-name"
 #define CFG_PARAM_APP_VER            "app-ver"
@ -87,6 +89,12 @@ struct RawGyroData {
    int16_t temp;   // Only for information (temperature of chip)
 };

+// Used for holding formulaData (used for calculating formula on device)
+struct RawFormulaData { 
+    double a[5];
+    double g[5];
+};
+
 // Main configuration class
 class Config {
    private:
@ -100,7 +108,7 @@ class Config {
        float  voltageFactor;
        float  tempSensorAdj;                   // This value will be added to the read sensor value
        int    sleepInterval;                
- 
+
        // Push target settings
        String brewfatherPushUrl;               // URL For brewfather

@ -118,7 +126,8 @@ class Config {
        char   gravityFormat;                   // G, P

        // Gyro calibration data
-        RawGyroData gyroCalibration;          // Holds the gyro calibration constants (6 * int16_t)
+        RawGyroData gyroCalibration;            // Holds the gyro calibration constants (6 * int16_t)
+        RawFormulaData formulaData;             // Used for creating formula

        void debug();
        void formatFileSystem();
@ -189,6 +198,9 @@ class Config {
        const RawGyroData& getGyroCalibration() { return gyroCalibration; }
        void               setGyroCalibration( const RawGyroData &r ) { gyroCalibration = r; saveNeeded = true; }

+        const RawFormulaData& getFormulaData() { return formulaData; }
+        void                  setFormulaData( const RawFormulaData &r ) { formulaData = r; saveNeeded = true; }
+
        // IO functions
        void createJson(DynamicJsonDocument& doc);
        bool saveFile();
--- a/src/gyro.h
+++ b/src/gyro.h
@ -28,7 +28,7 @@ SOFTWARE.
 //#define I2CDEV_IMPLEMENTATION I2CDEV_BUILTIN_SBWIRE

 // Includes
-#include <arduino.h>
+#include <Arduino.h>
 #include "MPU6050.h"
 #include "config.h"

--- a/src/main.cpp
+++ b/src/main.cpp
@ -39,7 +39,7 @@ SOFTWARE.
 DoubleResetDetector *drd;

 // Define constats for this program
-#if LOG_LEVEL==6 
+#ifdef DEACTIVATE_SLEEPMODE
 const int interval = 1000;                  // ms, time to wait between changes to output
 bool sleepModeAlwaysSkip = true;           // Web interface can override normal behaviour
 #else
@ -127,6 +127,11 @@ void setup() {
    if( dt ) 
        Log.notice(F("Main: Detected doubletap on reset." CR));

+#ifdef DEACTIVATE_SLEEPMODE
+    // If we are running in debug more we skip this part. makes is hard to debug in case of crash/watchdog reset
+    dt = false;
+#endif
+
    LOG_PERF_START("main-wifi-connect");
    myWifi.connect( dt );                   // This will return false if unable to connect to wifi, will be handled in loop()
    LOG_PERF_STOP("main-wifi-connect");
@ -241,7 +246,7 @@ void loop() {
        // Enter sleep mode if the conditions are right 
        // ------------------------------------------------------------------------------------------------
        //
-        if( goToSleep ) {
+        if( goToSleep && !sleepModeAlwaysSkip ) {
            Log.notice(F("MAIN: Entering deep sleep for %d s, run time %l s, battery=%F V." CR), sleepInterval, (millis()-runtimeMillis)/1000, volt );
            LittleFS.end();
            myGyro.enterSleep();
@ -267,10 +272,10 @@ void loop() {
        //LOG_PERF_STOP("loop-batt-read");

        loopMillis = millis();
-#if LOG_LEVEL==6
+//#if LOG_LEVEL==6
        Log.verbose(F("Main: Heap %d kb FreeSketch %d kb." CR), ESP.getFreeHeap()/1024, ESP.getFreeSketchSpace()/1024 );
        Log.verbose(F("Main: HeapFrag %d %%." CR), ESP.getHeapFragmentation() );
-#endif    
+//#endif    
    }

    myWebServer.loop();
--- a/src/resources.cpp
+++ b/src/resources.cpp
@ -21,6 +21,7 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 */
+#define INCBIN_OUTPUT_SECTION ".irom.text"
 #include <incbin.h>

 #if defined( EMBED_HTML )
@ -29,6 +30,7 @@ SOFTWARE.
 INCBIN(IndexHtm, "data/index.min.htm" );
 INCBIN(DeviceHtm, "data/device.min.htm" );
 INCBIN(ConfigHtm, "data/config.min.htm" );
+INCBIN(CalibrationHtm, "data/calibration.min.htm" );
 INCBIN(AboutHtm, "data/about.min.htm" );

 #else
--- a/src/tempsensor.cpp
+++ b/src/tempsensor.cpp
@ -58,8 +58,10 @@ void TempSensor::setup() {
    Log.notice(F("TSEN: Using temperature from gyro." CR));
 #else
    // This code is used to read the DS18 temp sensor
-    if( mySensors.getDS18Count() )
+    /*if( !mySensors.getDS18Count() ) {
+        Log.error(F("TSEN: No temperature sensors found." CR));
        return;
+    }*/

 #if LOG_LEVEL==6
    Log.verbose(F("TSEN: Looking for temp sensors." CR));
@ -107,6 +109,12 @@ float TempSensor::getValue() {
    Log.verbose(F("TSEN: Reciving temp value for gyro sensor %F C." CR), c);
 #endif
 #else
+    // If we dont have sensors just return 0
+    if( !mySensors.getDS18Count() ) {
+        Log.error(F("TSEN: No temperature sensors found. Skipping read." CR));
+        return -273;
+    }
+
    // Read the sensors
    //LOG_PERF_START("temp-request");
    mySensors.requestTemperatures();
--- a/src/webserver.cpp
+++ b/src/webserver.cpp
@ -39,6 +39,7 @@ SOFTWARE.
 INCBIN_EXTERN(IndexHtm);
 INCBIN_EXTERN(DeviceHtm);
 INCBIN_EXTERN(ConfigHtm);
+INCBIN_EXTERN(CalibrationHtm);
 INCBIN_EXTERN(AboutHtm);
 #else
 INCBIN_EXTERN(UploadHtm);
@ -46,6 +47,7 @@ INCBIN_EXTERN(UploadHtm);

 WebServer myWebServer;                  // My wrapper class fr webserver functions
 ESP8266WebServer server(80);
+int lastFormulaCreateError = 0; 

 extern bool sleepModeActive;
 extern bool sleepModeAlwaysSkip;
@ -116,10 +118,11 @@ void webHandleUpload() {
    Log.notice(F("WEB : webServer callback for /api/upload." CR));
    DynamicJsonDocument doc(100);

-    doc[ "index" ]  = myWebServer.checkHtmlFile( WebServer::HTML_INDEX );
-    doc[ "device" ] = myWebServer.checkHtmlFile( WebServer::HTML_DEVICE );
-    doc[ "config" ] = myWebServer.checkHtmlFile( WebServer::HTML_CONFIG );
-    doc[ "about" ]  = myWebServer.checkHtmlFile( WebServer::HTML_ABOUT );
+    doc[ "index" ]       = myWebServer.checkHtmlFile( WebServer::HTML_INDEX );
+    doc[ "device" ]      = myWebServer.checkHtmlFile( WebServer::HTML_DEVICE );
+    doc[ "config" ]      = myWebServer.checkHtmlFile( WebServer::HTML_CONFIG );
+    doc[ "calibration" ] = myWebServer.checkHtmlFile( WebServer::HTML_CALIBRATION );
+    doc[ "about" ]       = myWebServer.checkHtmlFile( WebServer::HTML_ABOUT );
    
 #if LOG_LEVEL==6
    serializeJson(doc, Serial);
@ -145,7 +148,7 @@ void webHandleUploadFile() {
    String f = upload.filename;
    bool validFilename = false;

-    if( f.equalsIgnoreCase("index.min.htm")  || f.equalsIgnoreCase("device.min.htm") ||
+    if( f.equalsIgnoreCase("index.min.htm")  || f.equalsIgnoreCase("device.min.htm") || f.equalsIgnoreCase("calibration.min.htm") ||
        f.equalsIgnoreCase("config.min.htm") || f.equalsIgnoreCase("about.min.htm")  ) {
            validFilename = true;
    }
@ -408,6 +411,127 @@ void webHandleConfigHardware() {
    LOG_PERF_STOP("webserver-api-config-hardware");
 }

+//
+// Callback from webServer when / has been accessed.
+//
+void webHandleFormulaRead() {
+    LOG_PERF_START("webserver-api-formula-read");
+#if LOG_LEVEL==6
+    Log.verbose(F("WEB : webServer callback for /api/formula/get." CR));
+#endif
+    DynamicJsonDocument doc(250);
+    const RawFormulaData& fd = myConfig.getFormulaData();
+
+#if LOG_LEVEL==6
+    Log.verbose(F("WEB : %F %F %F %F %F." CR), fd.a[0], fd.a[1], fd.a[2], fd.a[3], fd.a[4] );
+    Log.verbose(F("WEB : %F %F %F %F %F." CR), fd.g[0], fd.g[1], fd.g[2], fd.g[3], fd.g[4] );
+#endif
+
+    doc[ CFG_PARAM_ID ] = myConfig.getID();
+    doc[ CFG_PARAM_ANGLE ] = reduceFloatPrecision( myGyro.getAngle() );
+
+    switch( lastFormulaCreateError ) {
+        case ERR_FORMULA_INTERNAL:
+            doc[ CFG_PARAM_GRAVITY_FORMULA ] = "Internal error creating formula.";
+        break;
+        case ERR_FORMULA_NOTENOUGHVALUES:
+            doc[ CFG_PARAM_GRAVITY_FORMULA ] = "Not enough values to create formula.";
+        break;
+        case ERR_FORMULA_UNABLETOFFIND:
+            doc[ CFG_PARAM_GRAVITY_FORMULA ] = "Unable to find an accurate formula based on input.";
+        break;
+        default:
+            doc[ CFG_PARAM_GRAVITY_FORMULA ] = myConfig.getGravityFormula();
+        break;
+    }
+    
+    doc[ "a1" ] = reduceFloatPrecision( fd.a[0], 2);
+    doc[ "a2" ] = reduceFloatPrecision( fd.a[1], 2);
+    doc[ "a3" ] = reduceFloatPrecision( fd.a[2], 2);
+    doc[ "a4" ] = reduceFloatPrecision( fd.a[3], 2);
+    doc[ "a5" ] = reduceFloatPrecision( fd.a[4], 2);
+
+    doc[ "g1" ] = reduceFloatPrecision( fd.g[0], 4);
+    doc[ "g2" ] = reduceFloatPrecision( fd.g[1], 4);
+    doc[ "g3" ] = reduceFloatPrecision( fd.g[2], 4);
+    doc[ "g4" ] = reduceFloatPrecision( fd.g[3], 4);
+    doc[ "g5" ] = reduceFloatPrecision( fd.g[4], 4);
+
+#if LOG_LEVEL==6
+    serializeJson(doc, Serial);
+    Serial.print( CR );
+#endif    
+    String out;
+    serializeJson(doc, out);
+    server.send(200, "application/json", out.c_str() );
+    LOG_PERF_STOP("webserver-api-formula-read");
+}
+
+//
+// Update hardware settings.
+//
+void webHandleFormulaWrite() {
+    LOG_PERF_START("webserver-api-formula-write");
+    String id = server.arg( CFG_PARAM_ID );
+#if LOG_LEVEL==6
+    Log.verbose(F("WEB : webServer callback for /api/formula/post." CR) );
+#endif
+    if( !id.equalsIgnoreCase( myConfig.getID() ) ) {
+        Log.error(F("WEB : Wrong ID received %s, expected %s" CR), id.c_str(), myConfig.getID());
+        server.send(400, "text/plain", "Invalid ID.");
+        LOG_PERF_STOP("webserver-api-formula-write");
+        return;
+    }
+#if LOG_LEVEL==6
+    Log.verbose(F("WEB : angles=%F,%F,%F,%F,%F." CR), server.arg( "a1" ).toFloat(), server.arg( "a2" ).toFloat(), server.arg( "a3" ).toFloat(), server.arg( "a4" ).toFloat(), server.arg( "a5" ).toFloat() );
+    Log.verbose(F("WEB : gravity=%F,%F,%F,%F,%F." CR), server.arg( "g1" ).toFloat(), server.arg( "g2" ).toFloat(), server.arg( "g3" ).toFloat(), server.arg( "g4" ).toFloat(), server.arg( "g5" ).toFloat() );
+#endif
+    RawFormulaData fd;
+    fd.a[0] = server.arg( "a1" ).toDouble();
+    fd.a[1] = server.arg( "a2" ).toDouble();
+    fd.a[2] = server.arg( "a3" ).toDouble();
+    fd.a[3] = server.arg( "a4" ).toDouble();
+    fd.a[4] = server.arg( "a5" ).toDouble();
+    fd.g[0] = server.arg( "g1" ).toDouble();
+    fd.g[1] = server.arg( "g2" ).toDouble();
+    fd.g[2] = server.arg( "g3" ).toDouble();
+    fd.g[3] = server.arg( "g4" ).toDouble();
+    fd.g[4] = server.arg( "g5" ).toDouble();
+    myConfig.setFormulaData( fd );
+
+    int e;
+    char buf[100];
+
+    e = createFormula( fd, &buf[0], 4 );
+
+    if( e ) {
+        // If we fail with order=4 try with 3
+        Log.warning(F("WEB : Failed to find formula with order 4." CR), e );
+        e = createFormula( fd, &buf[0], 3 );
+    }
+
+    if( e ) {
+        // If we fail with order=3 try with 2
+        Log.warning(F("WEB : Failed to find formula with order 3." CR), e );
+        e = createFormula( fd, &buf[0], 2 );
+    }
+
+    if( e ) {
+        // If we fail with order=2 then we mark it as failed
+        Log.error(F("WEB : Unable to find formula based on provided values err=%d." CR), e );
+        lastFormulaCreateError = e;         
+    } else {
+        // Save the formula as succesful
+        Log.info(F("WEB : Found valid formula: '%s'" CR), &buf[0] );
+        myConfig.setGravityFormula( buf );
+        lastFormulaCreateError = 0;         
+    }
+
+    myConfig.saveFile();
+    server.sendHeader("Location", "/calibration.htm", true);  
+    server.send(302, "text/plain", "Formula updated" );
+    LOG_PERF_STOP("webserver-api-formula-write");
+}
 //
 // Helper function to check if files exist on file system.
 //
@ -422,6 +546,8 @@ const char* WebServer::getHtmlFileName( HtmlFile item ) {
        return "device.min.htm";
        case HTML_CONFIG:
        return "config.min.htm";
+        case HTML_CALIBRATION:
+        return "calibration.min.htm";
        case HTML_ABOUT:
        return "about.min.htm";
    }
@ -467,6 +593,9 @@ bool WebServer::setupWebServer() {
    server.on("/config.htm",[]() {
        server.send_P(200, "text/html", (const char*) gConfigHtmData, gConfigHtmSize );
    } );
+    server.on("/calibration.htm",[]() {
+        server.send_P(200, "text/html", (const char*) gCalibrationHtmData, gCalibrationHtmSize );
+    } );
    server.on("/about.htm",[]() {
        server.send_P(200, "text/html", (const char*) gAboutHtmData, gAboutHtmSize );
    } );
@ -490,6 +619,7 @@ bool WebServer::setupWebServer() {
        server.serveStatic("/device.htm", LittleFS, "/device.min.htm" );
        server.serveStatic("/config.htm", LittleFS, "/config.min.htm" );
        server.serveStatic("/about.htm", LittleFS, "/about.min.htm" );
+        server.serveStatic("/calibration.htm", LittleFS, "/calibration.min.htm" );

        // Also add the static upload view in case we we have issues that needs to be fixed.
        server.on("/upload.htm",[]() {
@ -507,6 +637,8 @@ bool WebServer::setupWebServer() {
    // Dynamic content
    server.on("/api/config", HTTP_GET, webHandleConfig);              // Get config.json
    server.on("/api/device", HTTP_GET, webHandleDevice);              // Get device.json
+    server.on("/api/formula", HTTP_GET, webHandleFormulaRead);        // Get formula.json (calibration page)
+    server.on("/api/formula", HTTP_POST, webHandleFormulaWrite);      // Get formula.json (calibration page)
    server.on("/api/calibrate", HTTP_POST, webHandleCalibrate);       // Run calibration routine (param id)
    server.on("/api/factory", HTTP_GET, webHandleFactoryReset);       // Reset the device
    server.on("/api/status", HTTP_GET, webHandleStatus);              // Get the status.json
--- a/src/webserver.h
+++ b/src/webserver.h
@ -33,7 +33,8 @@ class WebServer {
            HTML_INDEX = 0,
            HTML_DEVICE = 1,
            HTML_CONFIG = 2,
-            HTML_ABOUT = 3
+            HTML_ABOUT = 3,
+            HTML_CALIBRATION = 4
        };

        bool        setupWebServer();
--- a/src/wifi.cpp
+++ b/src/wifi.cpp
@ -32,36 +32,31 @@ SOFTWARE.
 #include <ESP8266HTTPClient.h>
 #include <ESP8266httpUpdate.h>
 #include <WiFiManager.h>   
+//#include <ESP_WiFiManager.h>                // TEST
+//#include <ESP_WiFiManager-Impl.h>           // TEST
 #include <LittleFS.h>
 #include <incbin.h>

 Wifi myWifi;
-WiFiManager myWifiManager; 
-bool shouldSaveConfig = false;

 const char* userSSID= USER_SSID;
 const char* userPWD = USER_SSID_PWD;

-//
-// Callback notifying us of the need to save config
-//
-void saveConfigCallback () {
-  shouldSaveConfig = true;
-}
-
 //
 // Connect to last known access point or create one if connection is not working. 
 //
 bool Wifi::connect( bool showPortal ) {
 #if LOG_LEVEL==6
    Log.verbose(F("WIFI: Connecting to WIFI via connection manager (portal=%s)." CR), showPortal?"true":"false");
+
+    WiFiManager myWifiManager; 
    myWifiManager.setDebugOutput(true);    
 #endif
    if( strlen(userSSID)==0 && showPortal ) {
        Log.notice(F("WIFI: Starting wifi portal." CR));

        myWifiManager.setBreakAfterConfig( true );
-        myWifiManager.setSaveConfigCallback(saveConfigCallback);
+        myWifiManager.setSaveConfigCallback(std::bind(&Wifi::setSaveConfig, this));
        myWifiManager.setMinimumSignalQuality(10);  
        myWifiManager.setClass("invert");
        myWifiManager.setHostname( myConfig.getMDNS() );
@ -82,6 +77,7 @@ bool Wifi::connect( bool showPortal ) {
    int i = 0;

    Log.notice(F("WIFI: Connecting to WIFI." CR));
+    //WiFi.persistent(false);
    WiFi.mode(WIFI_STA);
    if( strlen(userSSID) ) {
        Log.notice(F("WIFI: Connecting to wifi using predefined settings %s." CR), userSSID);
@ -97,16 +93,16 @@ bool Wifi::connect( bool showPortal ) {
        delay(100);
        Serial.print( "." );

-//        if( i++ > 60 ) {            // Try for 6 seconds.
        if( i++ > 200 ) {            // Try for 20 seconds.
-            Log.error(F("WIFI: Failed to connect to wifi, aborting." CR));
+            Log.error(F("WIFI: Failed to connect to wifi %d, aborting." CR), WiFi.status() );
+            WiFi.disconnect();
            return connectedFlag;   // Return to main that we have failed to connect.
        }
    }
    Serial.print( CR );
    connectedFlag = true;
    Log.notice(F("WIFI: Connected to wifi ip=%s." CR), getIPAddress().c_str() );
-    Log.notice(F("WIFI: Using mDNS name %s%s." CR), myConfig.getMDNS() );
+    Log.notice(F("WIFI: Using mDNS name %s." CR), myConfig.getMDNS() );
    return connectedFlag;
 }

--- a/src/wifi.h
+++ b/src/wifi.h
@ -31,12 +31,14 @@ SOFTWARE.
 class Wifi {
    private:
        // WIFI
-        bool      connectedFlag = false;
+        bool connectedFlag = false;
+        bool shouldSaveConfig = false;

        // OTA
        bool newFirmware = false;
        bool parseFirmwareVersionString( int (&num)[3], const char *version );
        void downloadFile(const char *fname);
+        void setSaveConfig() { shouldSaveConfig = true; }

    public:
        // WIFI
--- a/test/formula.json
+++ b/test/formula.json
@ -0,0 +1,14 @@
+{
+    "gravity-formula": "0.0*tilt^3+0.0*tilt^2+0.0017978*tilt+0.9436",
+    "angle": 45,
+    "a1": 25,
+    "a2": 35,
+    "a3": 45,
+    "a4": 55,
+    "a5": 65,
+    "g1": 1.000,
+    "g2": 1.010,
+    "g3": 1.020,
+    "g4": 1.030,
+    "g5": 1.040
+}
--- a/test/upload.json
+++ b/test/upload.json
@ -2,5 +2,6 @@
    "index": false,
    "device": false,
    "config": false,
+    "calibration": false,
    "about": true
 }