Add Example03 and setInputMultiplexer

Author: PaulZC

examples/Example03_InputMultiplexer/Example03_InputMultiplexer.ino

@@ -0,0 +1,82 @@
+/*
+  Configuring the ADS1219 ADC input multiplexer.
+
+  The ADS1219 has an input multiplexer which allows it to read:
+  single-ended voltages from AIN0/1/2/3;
+  differential voltages from AIN0-AIN1, AIN2-AIN3, AIN1-AIN2;
+  or the input can be shorted (to AVDD divided by two) for offset measurement.
+  This example shows how to configure the multiplexer and then read the voltage.
+
+  By: Paul Clark
+  SparkFun Electronics
+  Date: 2023/12/11
+  SparkFun code, firmware, and software is released under the MIT License.
+  Please see LICENSE.md for further details.
+
+  Hardware Connections:
+  IoT RedBoard --> ADS1219
+  QWIIC        --> QWIIC
+
+  Open the serial monitor at 115200 baud to see the voltage.
+
+  Feel like supporting our work? Buy a board from SparkFun!
+  https://www.sparkfun.com/products/23455 - Qwiic ADS1219 1x1
+*/
+
+// You will need the SparkFun Toolkit. Click here to get it: http://librarymanager/All#SparkFun_Toolkit
+
+#include <SparkFun_ADS1219.h> // Click here to get the library: http://librarymanager/All#SparkFun_ADS1219
+
+SfeADS1219ArdI2C myADC;
+
+void setup()
+{
+
+  delay(1000); // Allow time for the microcontroller to start up
+
+  Serial.begin(115200); // Begin the Serial console
+  while (!Serial)
+  {
+    delay(100); // Wait for the user to open the Serial Monitor
+  };
+  Serial.println("SparkFun ADS1219 Example");
+
+  Wire.begin(); // Begin the I2C bus
+
+  // Initialize ADC - this also performs a soft reset
+  while (myADC.begin() == false)
+  {
+    Serial.println("ADC failed to begin. Please check your wiring! Retrying...");
+    delay(1000);
+  }
+
+  // Configure the input multiplexer. Options are:
+  // ADS1219_CONFIG_MUX_DIFF_P0_N1 (Default)
+  // ADS1219_CONFIG_MUX_DIFF_P2_N3
+  // ADS1219_CONFIG_MUX_DIFF_P1_N2
+  // ADS1219_CONFIG_MUX_SINGLE_0
+  // ADS1219_CONFIG_MUX_SINGLE_1
+  // ADS1219_CONFIG_MUX_SINGLE_2
+  // ADS1219_CONFIG_MUX_SINGLE_3
+  // ADS1219_CONFIG_MUX_SHORTED
+  myADC.setInputMultiplexer(ADS1219_CONFIG_MUX_SINGLE_0); // Read the voltage between AIN0 and GND
+
+  Serial.println("ADC initialized");
+
+  Serial.println("Reading the voltage through the input multiplexer");
+}
+
+void loop()
+{
+  myADC.startSync(); // Start a single-shot conversion.
+
+  while (myADC.dataReady() == false) // Check if the conversion is complete. This will return true if data is ready.
+  {
+    delay(10); // The conversion is not complete. Wait a little to avoid pounding the I2C bus.
+  }
+
+  myADC.readConversion(); // Read the conversion result from the ADC. Store it internally.
+  float milliVolts = myADC.getConversionMillivolts(); // Convert to millivolts.
+  Serial.print("ADC voltage (mV): ");
+  Serial.println(milliVolts, 3); // Print milliVolts with 3 decimal places
+}

src/SparkFun_ADS1219.cpp

@@ -65,7 +65,18 @@ bool SfeADS1219Driver::setConversionMode(const ads1219_conversion_mode_config_t
     sfe_ads1219_reg_cfg_t config;
     if (_theBus->readRegisterByte(kSfeADS1219RegConfigRead, config.byte) != kSTkErrOk) // Read the config register
         return false;
-    config.cm = (uint8_t)mode; // Update (only) the conversion mode
+    config.cm = (uint8_t)mode; // Modify (only) the conversion mode
+    return (_theBus->writeRegisterByte(kSfeADS1219RegConfigWrite, config.byte) == kSTkErrOk); // Write the config register
+}
+
+/// @brief Configure the input multiplexer.
+/// @return True if successful, false otherwise.
+bool SfeADS1219Driver::setInputMultiplexer(const ads1219_input_multiplexer_config_t mux)
+{
+    sfe_ads1219_reg_cfg_t config;
+    if (_theBus->readRegisterByte(kSfeADS1219RegConfigRead, config.byte) != kSTkErrOk) // Read the config register
+        return false;
+    config.mux = (uint8_t)mux; // Modify (only) the input multiplexer
     return (_theBus->writeRegisterByte(kSfeADS1219RegConfigWrite, config.byte) == kSTkErrOk); // Write the config register
 }
 

src/SparkFun_ADS1219.h

@@ -174,14 +174,14 @@ class SfeADS1219Driver
     /// @return true if successful, false otherwise.
     bool readConversion(void);
 
-    /// @brief Configure the input multiplexer.
-    /// @return True if successful, false otherwise.
-    bool setInputMultiplexer(const ads1219_input_multiplexer_config_t config = ADS1219_CONFIG_MUX_DIFF_P0_N1);
-
     /// @brief Configure the conversion mode.
     /// @return True if successful, false otherwise.
     bool setConversionMode(const ads1219_conversion_mode_config_t mode = ADS1219_CONVERSION_SINGLE_SHOT);
 
+    /// @brief Configure the input multiplexer.
+    /// @return True if successful, false otherwise.
+    bool setInputMultiplexer(const ads1219_input_multiplexer_config_t config = ADS1219_CONFIG_MUX_DIFF_P0_N1);
+
     /// @brief  Return the conversion result which was read by readConversion.
     /// Convert it to mV using referenceVoltageMillivolts and the _adcGain.
     /// @param  referenceVoltageMillivolts Usually the internal 2.048V reference voltage.