Added Example2. Added more debug messages.

Author: PaulZC

examples/Example1_Simple/Example1_Simple.ino

@@ -19,6 +19,8 @@ This code is released under the MIT license.
 Distributed as-is; no warranty is given.
 ******************************************************************************/
 
+#include <Wire.h> // Needed for I2C
+
 #include <SparkFun_MAX1704x_Fuel_Gauge_Arduino_Library.h> // Click here to get the library: http://librarymanager/All#SparkFun_MAX1704x_Fuel_Gauge_Arduino_Library
 
 SFE_MAX1704X lipo;
@@ -30,9 +32,21 @@ bool alert; // Variable to keep track of whether alert has been triggered
 void setup()
 {
 	Serial.begin(115200); // Start serial, to output debug data
+  while (!Serial)
+    ; //Wait for user to open terminal
+  Serial.println(F("MAX17043 / MAX17044 Example"));
+
+  Wire.begin();
+
+  lipo.enableDebugging(); // Uncomment this line to enable helpful debug messages on Serial
 
-	// Set up the MAX17043 LiPo fuel gauge:
-	lipo.begin(); // Initialize the MAX17043 LiPo fuel gauge
+  // Set up the MAX17043 LiPo fuel gauge:
+  if (lipo.begin() == false) // Connect to the MAX17043 using the default wire port
+  {
+    Serial.println(F("MAX17043 / MAX17044 not detected. Please check wiring. Freezing."));
+    while (1)
+      ;
+  }
 
 	// Quick start restarts the MAX17043 in hopes of getting a more accurate
 	// guess for the SOC.

examples/Example2_AlternatePorts/Example2_AlternatePorts.ino

@@ -0,0 +1,87 @@
+/******************************************************************************
+Example2_AlternatePorts
+By: Paul Clark
+Date: October 23rd 2020
+
+Based extensively on:
+MAX17043_Simple_Serial.cpp
+SparkFun MAX17043 Example Code
+Jim Lindblom @ SparkFun Electronics
+Original Creation Date: June 22, 2015
+
+This file demonstrates the simple API of the SparkFun MAX17043 Arduino library using non-standard Wire and Serial ports.
+
+This example will print the gauge's voltage and state-of-charge (SOC) readings
+to serial (115200 baud)
+
+This code is released under the MIT license.
+
+Distributed as-is; no warranty is given.
+******************************************************************************/
+
+#include <Wire.h> // Needed for I2C
+
+#include <SparkFun_MAX1704x_Fuel_Gauge_Arduino_Library.h> // Click here to get the library: http://librarymanager/All#SparkFun_MAX1704x_Fuel_Gauge_Arduino_Library
+
+SFE_MAX1704X lipo;
+
+// Define our non-standard ports:
+#define mySerial Serial1
+TwoWire myWire(0);
+
+double voltage = 0; // Variable to keep track of LiPo voltage
+double soc = 0; // Variable to keep track of LiPo state-of-charge (SOC)
+bool alert; // Variable to keep track of whether alert has been triggered
+
+void setup()
+{
+	mySerial.begin(115200); // Start serial, to output debug data
+  while (!mySerial)
+    ; //Wait for user to open terminal
+  mySerial.println(F("MAX17043 / MAX17044 Example"));
+
+  myWire.begin();
+
+  lipo.enableDebugging(mySerial); // Uncomment this line to enable helpful debug messages on non-standard serial
+
+  // Set up the MAX17043 LiPo fuel gauge:
+  if (lipo.begin(myWire) == false) // Connect to the MAX17043 using non-standard wire port
+  {
+    mySerial.println(F("MAX17043 / MAX17044 not detected. Please check wiring. Freezing."));
+    while (1)
+      ;
+  }
+
+	// Quick start restarts the MAX17043 in hopes of getting a more accurate
+	// guess for the SOC.
+	lipo.quickStart();
+
+	// We can set an interrupt to alert when the battery SoC gets too low.
+	// We can alert at anywhere between 1% - 32%:
+	lipo.setThreshold(20); // Set alert threshold to 20%.
+}
+
+void loop()
+{
+	// lipo.getVoltage() returns a voltage value (e.g. 3.93)
+	voltage = lipo.getVoltage();
+	// lipo.getSOC() returns the estimated state of charge (e.g. 79%)
+	soc = lipo.getSOC();
+	// lipo.getAlert() returns a 0 or 1 (0=alert not triggered)
+	alert = lipo.getAlert();
+
+	// Print the variables:
+	mySerial.print("Voltage: ");
+	mySerial.print(voltage);  // Print the battery voltage
+	mySerial.println(" V");
+
+	mySerial.print("Alert: ");
+	mySerial.println(alert);
+
+	mySerial.print("Percentage: ");
+	mySerial.print(soc); // Print the battery state of charge
+	mySerial.println(" %");
+	mySerial.println();
+
+	delay(500);
+}

src/SparkFun_MAX1704x_Fuel_Gauge_Arduino_Library.cpp

@@ -159,7 +159,13 @@ uint8_t SFE_MAX1704X::sleep()
   // Read config reg, so we don't modify any other values:
   uint16_t configReg = read16(MAX17043_CONFIG);
   if (configReg & (1<<7))
-    return 5; // Already sleeping, do nothing but return an error
+  {
+    if (_printDebug == true)
+    {
+      _debugPort->println(F("sleep: MAX17043 is already sleeping!"));
+    }
+    return MAX17043_GENERIC_ERROR; // Already sleeping, do nothing but return an error
+  }
   configReg |= (1<<7); // Set sleep bit
 
   return write16(configReg, MAX17043_CONFIG);
@@ -170,7 +176,13 @@ uint8_t SFE_MAX1704X::wake()
   // Read config reg, so we don't modify any other values:
   uint16_t configReg = read16(MAX17043_CONFIG);
   if (!(configReg & (1<<7)))
-    return 5; // Already awake, do nothing but return an error
+  {
+    if (_printDebug == true)
+    {
+      _debugPort->println(F("sleep: MAX17043 is already awake!"));
+    }
+    return MAX17043_GENERIC_ERROR; // Already sleeping, do nothing but return an error
+  }
   configReg &= ~(1<<7); // Clear sleep bit
 
   return write16(configReg, MAX17043_CONFIG);

src/SparkFun_MAX1704x_Fuel_Gauge_Arduino_Library.h

@@ -64,6 +64,16 @@ Distributed as-is; no warranty is given.
 ////////////////////////////////
 #define MAX17043_ADDRESS  0x36 // Unshifted I2C address. Becomes 0x6C for write and 0x6D for read.
 
+// Generic error:
+// Wire.endTransmission will return:
+// 0:success
+// 1:data too long to fit in transmit buffer
+// 2:received NACK on transmit of address
+// 3:received NACK on transmit of data
+// 4:other error
+// So, let's use "5" as a generic error value
+#define MAX17043_GENERIC_ERROR 5
+
 class SFE_MAX1704X
 {
 public: