Merge pull request #376 from sparkfun/Fix_#356

Fix #356

Author: nseidle

Firmware/RTK_Everywhere/States.ino

@@ -260,8 +260,9 @@ void stateUpdate()
             // Check for <1m horz accuracy before starting surveyIn
             char accuracy[20];
             char temp[20];
-            const char *units = getHpaUnits(hpa, temp, sizeof(temp), 2);
-            const char *accUnits = getHpaUnits(gnssGetSurveyInStartingAccuracy(), accuracy, sizeof(accuracy), 2);
+            const char *units = getHpaUnits(hpa, temp, sizeof(temp), 2, true);
+            // gnssGetSurveyInStartingAccuracy is 10m max
+            const char *accUnits = getHpaUnits(gnssGetSurveyInStartingAccuracy(), accuracy, sizeof(accuracy), 2, false);
             systemPrintf("Waiting for Horz Accuracy < %s (%s): %s%s%s%s, SIV: %d\r\n", accuracy, accUnits, temp,
                          (accUnits != units) ? " (" : "", (accUnits != units) ? units : "",
                          (accUnits != units) ? ")" : "", siv);
@@ -313,7 +314,7 @@ void stateUpdate()
             else
             {
                 char temp[20];
-                const char *units = getHpaUnits(meanAccuracy, temp, sizeof(temp), 3);
+                const char *units = getHpaUnits(meanAccuracy, temp, sizeof(temp), 3, true);
                 systemPrintf("Time elapsed: %d Accuracy (%s): %s SIV: %d\r\n", observationTime, units, temp, siv);
 
                 if (observationTime > maxSurveyInWait_s)

Firmware/RTK_Everywhere/System.ino

@@ -369,7 +369,7 @@ void printReports()
 
                 char modifiedHpa[20];
                 const char *hpaUnits =
-                    getHpaUnits(hpa, modifiedHpa, sizeof(modifiedHpa), 3); // Returns string of the HPA units
+                    getHpaUnits(hpa, modifiedHpa, sizeof(modifiedHpa), 3, true); // Returns string of the HPA units
 
                 systemPrintf("Rover Accuracy (%s): %s, SIV: %d GNSS State: ", hpaUnits, modifiedHpa,
                              gnssGetSatellitesInView());
@@ -716,44 +716,49 @@ void reportFatalError(const char *errorMsg)
     }
 }
 
-// Returns string of the HPA units
-const char *getHpaUnits(double hpa, char *buffer, int length, int decimals)
+// This allows the measurementScaleTable to be alphabetised if desired
+int measurementScaleToIndex(uint8_t scale)
 {
-    const char *units;
-
-    // Return the units
-    if (settings.measurementScale >= MEASUREMENT_SCALE_MAX)
+    for (int i = 0; i < MEASUREMENT_UNITS_MAX; i++)
     {
-        units = "Unknown";
-        strcpy(buffer, "Unknown");
+        if (measurementScaleTable[i].measurementUnit == scale)
+            return i;
     }
-    else
+
+    return -1; // This should never happen...
+}
+
+// Returns string of the HPA units
+const char *getHpaUnits(double hpa, char *buffer, int length, int decimals, bool limit)
+{
+    static const char unknown[] = "Unknown";
+
+    int i = measurementScaleToIndex(settings.measurementScale);
+    if (i >= 0)
     {
-        units = measurementScaleUnits[settings.measurementScale];
+        const char *units = measurementScaleTable[i].measurementScale1NameShort;
 
-        // Convert the HPA value to a string
-        switch (settings.measurementScale)
+        hpa *= measurementScaleTable[i].multiplierMetersToScale1; // Scale1: m->m or m->ft
+
+        bool limited = false;
+        if (limit && (hpa > measurementScaleTable[i].reportingLimitScale1)) // Limit the reported accuracy (Scale1)
         {
-        case MEASUREMENTS_IN_METERS:
-            snprintf(buffer, length, "%.*f", decimals, hpa);
-            break;
+            limited = true;
+            hpa = measurementScaleTable[i].reportingLimitScale1;
+        }
 
-        case MEASUREMENTS_IN_FEET_INCHES:
-            double inches;
-            double feet;
-            inches = hpa * INCHES_IN_A_METER;
-            feet = inches / 12.;
-            if (inches >= 36.)
-                snprintf(buffer, length, "%.*f", decimals, feet);
-            else
-            {
-                units = "in";
-                snprintf(buffer, length, "%.*f", decimals, inches);
-            }
-            break;
+        if (hpa <= measurementScaleTable[i].changeFromScale1To2At) // Scale2: m->m or ft->in
+        {
+            hpa *= measurementScaleTable[i].multiplierScale1To2;
+            units = measurementScaleTable[i].measurementScale2NameShort;
         }
+
+        snprintf(buffer, length, "%s%.*f", limited ? "> " : "", decimals, hpa);
+        return units;
     }
-    return units;
+
+    strncpy(buffer, unknown, length);
+    return unknown;
 }
 
 // Helper method to convert GNSS time and date into Unix Epoch

Firmware/RTK_Everywhere/menuSystem.ino

@@ -224,7 +224,8 @@ void menuSystem()
 
         systemPrintln("r) Reset all settings to default");
 
-        systemPrintf("u) Toggle printed measurement scale: %s\r\n", measurementScaleName[settings.measurementScale]);
+        systemPrintf("u) Printed measurement units: %s\r\n",
+            measurementScaleTable[measurementScaleToIndex(settings.measurementScale)].measurementScaleName);
 
         systemPrintf("z) Set time zone offset: %02d:%02d:%02d\r\n", settings.timeZoneHours, settings.timeZoneMinutes,
                      settings.timeZoneSeconds);
@@ -294,7 +295,7 @@ void menuSystem()
         else if (incoming == 'u')
         {
             settings.measurementScale += 1;
-            if (settings.measurementScale >= MEASUREMENT_SCALE_MAX)
+            if (settings.measurementScale >= MEASUREMENT_UNITS_MAX)
                 settings.measurementScale = 0;
         }
         else if (incoming == 'z')
@@ -1353,7 +1354,7 @@ void printCurrentConditions()
 
         float hpa = gnssGetHorizontalAccuracy();
         char temp[20];
-        const char *units = getHpaUnits(hpa, temp, sizeof(temp), 3);
+        const char *units = getHpaUnits(hpa, temp, sizeof(temp), 3, true);
         systemPrintf(", HPA (%s): %s", units, temp);
 
         systemPrint(", Lat: ");

Firmware/RTK_Everywhere/settings.h

@@ -599,29 +599,34 @@ enum PeriodDisplayValues
 #define PERIODIC_SETTING(x) (settings.periodicDisplay & PERIODIC_MASK(x))
 #define PERIODIC_TOGGLE(x) settings.periodicDisplay = settings.periodicDisplay ^ PERIODIC_MASK(x)
 
-#define INCHES_IN_A_METER       39.37009424
+#define INCHES_IN_A_METER   39.37007874
+#define FEET_IN_A_METER     3.280839895
 
-enum MeasurementScale
-{
-    MEASUREMENTS_IN_METERS = 0,
-    MEASUREMENTS_IN_FEET_INCHES,
-    // Add new measurement scales above this line
-    MEASUREMENT_SCALE_MAX
-};
-
-const char * const measurementScaleName[] =
+typedef enum
 {
-    "meters",
-    "feet and inches",
-};
-const int measurementScaleNameEntries = sizeof(measurementScaleName) / sizeof(measurementScaleName[0]);
+    MEASUREMENT_UNITS_METERS = 0,
+    MEASUREMENT_UNITS_FEET_INCHES,
+    // Add new measurement units above this line
+    MEASUREMENT_UNITS_MAX
+} measurementUnits;
 
-const char * const measurementScaleUnits[] =
+typedef struct
 {
-    "m",
-    "ft",
+    const measurementUnits measurementUnit;
+    const char *measurementScaleName;
+    const char *measurementScale1NameShort;
+    const char *measurementScale2NameShort;
+    const double multiplierMetersToScale1;
+    const double changeFromScale1To2At;
+    const double multiplierScale1To2;
+    const double reportingLimitScale1;
+} measurementScaleEntry;
+
+const measurementScaleEntry measurementScaleTable[] = {
+    { MEASUREMENT_UNITS_METERS, "meters", "m", "m", 1.0, 1.0, 1.0, 30.0 },
+    { MEASUREMENT_UNITS_FEET_INCHES, "feet and inches", "ft", "in", FEET_IN_A_METER, 3.0, 12.0, 100.0 }
 };
-const int measurementScaleUnitsEntries = sizeof(measurementScaleUnits) / sizeof(measurementScaleUnits[0]);
+const int measurementScaleEntries = sizeof(measurementScaleTable) / sizeof(measurementScaleTable[0]);
 
 // These are the allowable messages to broadcast and log (if enabled)
 
@@ -1190,7 +1195,7 @@ struct Settings
     uint8_t handleGnssDataTaskCore = 1;     // Core where task should run, 0=core, 1=Arduino
     uint8_t handleGnssDataTaskPriority = 1; // Read from the cicular buffer and dole out to end points (SD, TCP, BT).
     uint8_t i2cInterruptsCore = 1; // Core where hardware is started and interrupts are assigned to, 0=core, 1=Arduino
-    uint8_t measurementScale = MEASUREMENTS_IN_METERS;
+    uint8_t measurementScale = MEASUREMENT_UNITS_METERS;
     bool printBootTimes = false; // Print times and deltas during boot
     bool printPartitionTable = false;
     bool printTaskStartStop = false;

Firmware/RTK_Everywhere/support.ino

@@ -668,10 +668,8 @@ void verifyTables()
         reportFatalError("Fix platformProvisionTable to match ProductVariant");
 
     // Verify the measurement scales
-    if (measurementScaleNameEntries != MEASUREMENT_SCALE_MAX)
-        reportFatalError("Fix measurementScaleName to match MeasurementScale");
-    if (measurementScaleUnitsEntries != MEASUREMENT_SCALE_MAX)
-        reportFatalError("Fix measurementScaleUnits to match MeasurementScale");
+    if (measurementScaleEntries != MEASUREMENT_UNITS_MAX)
+        reportFatalError("Fix measurementScaleTable to match measurementUnits");
 
     // Verify the consistency of the internal tables
     ethernetVerifyTables();