fix #133 overflow of exponent

+ added readme.md
+ some cleanup

libraries/Max44009/Max44009.h

@@ -3,7 +3,7 @@
 //
 //    FILE: Max44009.h
 //  AUTHOR: Rob dot Tillaart at gmail dot com
-// VERSION: 0.2.0
+// VERSION: 0.3.1
 // PURPOSE: library for MAX44009 lux sensor Arduino
 // HISTORY: See Max440099.cpp
 //
@@ -18,9 +18,9 @@
 #include "WProgram.h"
 #endif
 
-#define MAX44009_LIB_VERSION     "0.3.0"
-#define MAX44009_DEFAULT_ADDRESS 0x4A
-#define MAX44009_ALT_ADDRESS     0x4B
+#define MAX44009_LIB_VERSION        "0.3.1"
+#define MAX44009_DEFAULT_ADDRESS    0x4A
+#define MAX44009_ALT_ADDRESS        0x4B
 
 // REGISTERS
 #define MAX44009_INTERRUPT_STATUS   0x00
@@ -38,6 +38,11 @@
 #define MAX44009_CFG_CDR            0x08
 #define MAX44009_CFG_TIMER          0x07
 
+// ERROR CODES
+#define MAX44009_OK		                 0
+#define MAX44009_ERROR_WIRE_REQUEST    -10
+#define MAX44009_ERROR_OVERFLOW        -20
+
 
 class Max44009
 {
@@ -84,10 +89,10 @@ public:
     // 001  400ms
     // 010  200ms
     // 011  100ms
-    // 100   50ms
-    // 101   25ms
-    // 110   12.5ms
-    // 111    6.25ms
+    // 100   50ms       manual only
+    // 101   25ms       manual only
+    // 110   12.5ms     manual only
+    // 111    6.25ms    manual only
     void    setManualMode(uint8_t CDR, uint8_t TIM);
 
 private:

libraries/Max44009/examples/max44009_test01/max44009_test01.ino

@@ -11,7 +11,7 @@
 #include "Wire.h"
 #include "Max44009.h"
 
-Max44009 myLux(MAX44009_DEFAULT_ADDRESS);
+Max44009 myLux(0xCB);         // default addr
 
 uint32_t lastDisplay = 0;
 

libraries/Max44009/library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/Arduino.git"
   },
-  "version":"0.2.0",
+  "version": "0.3.1",
   "frameworks": "arduino",
   "platforms": "*",
   "export": {

libraries/Max44009/library.properties

@@ -1,5 +1,5 @@
 name=Max44009
-version=0.2.0
+version=0.3.1
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Library for MAX44009 lux sensor Arduino. 

libraries/Max44009/max44009.cpp

@@ -1,12 +1,14 @@
 //
 //    FILE: Max44009.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.2.0
+// VERSION: 0.3.1
 // PURPOSE: library for MAX44009 lux sensor Arduino
 //     URL: https://github.com/RobTillaart/Arduino/tree/master/libraries
 //
 // Released to the public domain
 //
+// 0.3.1  - 2020-01-21 issue #133 overflow of the exponent
+// 0.3.0  - 2020-01-20 issue #141 Kudos to Moritz89
 // 0.2.0  - 2019-08-23 solve #127 == redo #118
 // 0.1.10 - 2018-12-08 issue #118 Fix constructor esp8266
 //          (thanks to Bolukan)
@@ -30,7 +32,7 @@ Max44009::Max44009(const uint8_t address, const uint8_t dataPin, const uint8_t c
 {
     _address = address;
     _data = 0;
-    _error = 0;
+    _error = MAX44009_OK;
     _wire = &Wire;
 
     if ((dataPin < 255) && (clockPin < 255))
@@ -39,7 +41,6 @@ Max44009::Max44009(const uint8_t address, const uint8_t dataPin, const uint8_t c
     } else {
         _wire->begin();
     }
-    // TWBR = 12; // _wire->setClock(400000);
 }
 #endif
 
@@ -47,28 +48,30 @@ Max44009::Max44009(const uint8_t address, Boolean begin)
 {
     _address = address;
     _data = 0;
-    _error = 0;
+    _error = MAX44009_OK;
     _wire = &Wire;
 
-    if(begin == Boolean::True) {
+    if (begin == Boolean::True)
+    {
       _wire->begin();
     }
-    // TWBR = 12; // _wire->setClock(400000);
 }
 
 Max44009::Max44009(const Boolean begin)
 {
     _address = MAX44009_DEFAULT_ADDRESS;
     _data = 0;
-    _error = 0;
+    _error = MAX44009_OK;
     _wire = &Wire;
 
-    if(begin == Boolean::True) {
+    if (begin == Boolean::True)
+    {
       _wire->begin();
     }
 }
 
-void Max44009::configure(const uint8_t address, TwoWire *wire) {
+void Max44009::configure(const uint8_t address, TwoWire *wire)
+{
     _address = address;
     _wire = wire;
 }
@@ -78,6 +81,11 @@ float Max44009::getLux(void)
     uint8_t dhi = read(MAX44009_LUX_READING_HIGH);
     uint8_t dlo = read(MAX44009_LUX_READING_LOW);
     uint8_t e = dhi >> 4;
+    if (e == 0x0F)
+    {
+        _error = MAX44009_ERROR_OVERFLOW;
+        return -1;
+    }
     uint32_t m = ((dhi & 0x0F) << 4) + (dlo & 0x0F);
     m <<= e;
     float val = m * 0.045;
@@ -87,7 +95,7 @@ float Max44009::getLux(void)
 int Max44009::getError()
 {
     int e = _error;
-    _error = 0;
+    _error = MAX44009_OK;
     return e;
 }
 
@@ -154,7 +162,7 @@ void Max44009::setManualMode(uint8_t CDR, uint8_t TIM)
     uint8_t config = read(MAX44009_CONFIGURATION);
     config &= ~MAX44009_CFG_CONTINUOUS; // off
     config |= MAX44009_CFG_MANUAL;      // on
-    config &= 0xF0; // clear CDR & TIM bits
+    config &= 0xF0;                     // clear CDR & TIM bits
     config |= CDR << 3 | TIM;
     write(MAX44009_CONFIGURATION, config);
 }
@@ -193,13 +201,13 @@ uint8_t Max44009::read(uint8_t reg)
     _wire->beginTransmission(_address);
     _wire->write(reg);
     _error = _wire->endTransmission();
-    if (_error != 0)
+    if (_error != MAX44009_OK)
     {
         return _data; // last value
     }
     if (_wire->requestFrom(_address, (uint8_t) 1) != 1)
     {
-        _error = 10;
+        _error = MAX44009_ERROR_WIRE_REQUEST;
         return _data; // last value
     }
 #if (ARDUINO <  100)

libraries/Max44009/readme.md

@@ -0,0 +1,13 @@
+
+MAX44009 I2C LUX sensor
+====
+
+About examples
+----
+__Max44009\examples\max44009_test01__
+- use for e.g. UNO
+
+__Max44009\examples\max44009_test02__
+- will not compile for UNO
+- use for e.g. ESP32
+