Implement begin and configure for a char lcd

Author: brentru

platformio.ini

@@ -90,6 +90,7 @@ lib_deps =
     https://github.com/bblanchon/ArduinoStreamUtils.git
     https://github.com/Sensirion/arduino-i2c-scd4x.git
     https://github.com/adafruit/Adafruit_LED_Backpack.git
+    https://github.com/adafruit/Adafruit_LiquidCrystal.git
 
 ; Common build environment for ESP32 platform
 [common:esp32]

src/components/i2c/controller.cpp

@@ -365,6 +365,11 @@ static const std::map<std::string, FnCreateI2cOutputDrv> I2cFactoryOutput = {
      [](TwoWire *i2c, uint16_t addr, uint32_t mux_channel,
         const char *driver_name) -> drvOutputBase * {
        return new drvOutQuadAlphaNum(i2c, addr, mux_channel, driver_name);
+     }},
+    {"charlcd",
+     [](TwoWire *i2c, uint16_t addr, uint32_t mux_channel,
+        const char *driver_name) -> drvOutputBase * {
+       return new drvOutCharLcd(i2c, addr, mux_channel, driver_name);
      }}}; ///< I2C output driver factory
 
 /*!
@@ -822,14 +827,14 @@ bool I2cController::Handle_I2cDeviceOutputWrite(pb_istream_t *stream) {
 
   // Determine which driver cb function to use
   if (_i2c_model->GetI2cDeviceOutputWriteMsg()->has_led_backpack_write) {
-    WS_DEBUG_PRINTLN("[i2c] Writing message to LED backpack...");
     if (!driver->LedBackpackWrite(
             &_i2c_model->GetI2cDeviceOutputWriteMsg()->led_backpack_write)) {
       WS_DEBUG_PRINTLN("[i2c] ERROR: Unable to write to LED backpack!");
       return false;
     }
   } else if (_i2c_model->GetI2cDeviceOutputWriteMsg()->has_char_lcd_write) {
     WS_DEBUG_PRINTLN("[i2c] Char LCD write not implemented yet!");
+    // TODO!
   } else {
     WS_DEBUG_PRINTLN("[i2c] ERROR: Unable to determine I2C Output Write type!");
     return false;
@@ -1053,7 +1058,6 @@ bool I2cController::Handle_I2cDeviceAddOrReplace(pb_istream_t *stream) {
     _i2c_drivers_output.push_back(drv_out);
   }
 
-  
   WS_DEBUG_PRINTLN("[i2c] Driver initialized and added to controller: ");
   WS_DEBUG_PRINTLN(device_name);
 

src/components/i2c/controller.h

@@ -45,6 +45,7 @@
 #include "drivers/drvMprls.h"
 #include "drivers/drvMs8607.h"
 #include "drivers/drvNau7802.h"
+#include "drivers/drvOutCharLcd.h"
 #include "drivers/drvOutQuadAlphaNum.h"
 #include "drivers/drvOutputBase.h" ///< Base i2c output driver class
 #include "drivers/drvPct2075.h"

src/components/i2c/drivers/drvOutCharLcd.h

@@ -0,0 +1,89 @@
+/*!
+ * @file drvOutCharLcd.h
+ *
+ * Device driver for I2C Character LCDs (HD44780)
+ *
+ * Adafruit invests time and resources providing this open source code,
+ * please support Adafruit and open-source hardware by purchasing
+ * products from Adafruit!
+ *
+ * Copyright (c) Brent Rubell for Adafruit Industries 2025
+ *
+ * MIT license, all text here must be included in any redistribution.
+ *
+ */
+
+#ifndef DRV_OUT_CHAR_LCD
+#define DRV_OUT_CHAR_LCD
+
+#include "drvOutputBase.h"
+#include <Adafruit_LiquidCrystal.h>
+#include <Arduino.h>
+
+/*!
+    @brief  Class that provides a driver interface for a lcd character display.
+            This class is a wrapper around the Adafruit_LiquidCrystal library.
+*/
+class drvOutCharLcd : public drvOutputBase {
+public:
+  /*!
+      @brief    Constructor for a lcd character display.
+      @param    i2c
+                The I2C interface.
+      @param    sensorAddress
+                7-bit device address.
+      @param    mux_channel
+                The I2C multiplexer channel.
+      @param    driver_name
+                The name of the driver.
+  */
+  drvOutCharLcd(TwoWire *i2c, uint16_t sensorAddress, uint32_t mux_channel,
+                const char *driver_name)
+      : drvOutputBase(i2c, sensorAddress, mux_channel, driver_name) {
+    // Initialization handled by drvOutPutBase constructor
+  }
+
+  /*!
+      @brief    Destructor for a quad alphanumeric display.
+  */
+  ~drvOutCharLcd() {
+    if (_lcd) {
+      delete _lcd;
+      _lcd = nullptr;
+    }
+  }
+
+  /*!
+      @brief    Initializes an I2C character LCD and begins I2C communication.
+      @returns  True if initialized successfully, False otherwise.
+  */
+  bool begin() override {
+    _lcd = new Adafruit_LiquidCrystal(_address, _i2c);
+    bool did_begin = _lcd->begin(_cols, _rows);
+    if (did_begin && _enable_backlight) {
+      _lcd->setBacklight(LOW);
+    }
+    return did_begin;
+  }
+
+  /*!
+      @brief    Writes a message to the LCD.
+      @note     MUST be called prior to begin() to configure the LCD's size
+      @param    message
+                The message to be displayed.
+  */
+  void ConfigureCharLcd(uint8_t rows, uint8_t cols, bool enable_backlight) {
+    _rows = rows;
+    _cols = cols;
+    _enable_backlight = enable_backlight;
+  }
+
+protected:
+  Adafruit_LiquidCrystal
+      *_lcd;              ///< Pointer to the Adafruit_LiquidCrystal object
+  uint8_t _rows = 2;      ///< Number of rows in the display
+  uint8_t _cols = 16;     ///< Number of columns in the display
+  bool _enable_backlight; ///< Flag to enable/disable backlight
+};
+
+#endif // DRV_OUT_CHAR_LCD

src/components/i2c/drivers/drvOutQuadAlphaNum.h

@@ -133,17 +133,6 @@ class drvOutQuadAlphaNum : public drvOutputBase {
       pos_start = LED_MAX_CHARS - seg_chars;
     }
 
-
-    WS_DEBUG_PRINT("Message to display: ");
-    WS_DEBUG_PRINTLN(message);
-    WS_DEBUG_PRINT(" with len_display: ");
-    WS_DEBUG_PRINTLN(len_display);
-    WS_DEBUG_PRINT(" at pos_start: ");
-    WS_DEBUG_PRINTLN(pos_start);
-
-    // TODO FRIDAY
-    // NOTE: If there's a ., increment len_display by 1 to account for the decimal
-
     // Write to the display's buffer
     int cur_idx = pos_start;
     for (size_t i = 0; i < len_display; i++) {
@@ -159,12 +148,6 @@ class drvOutQuadAlphaNum : public drvOutputBase {
       }
 
       // Write the character to the display buffer
-      WS_DEBUG_PRINT("Writing char: ");
-      WS_DEBUG_PRINT(ch);
-      WS_DEBUG_PRINT(" at index: ");
-      WS_DEBUG_PRINT(cur_idx);
-      WS_DEBUG_PRINT(" with dot: ");
-      WS_DEBUG_PRINTLN(display_dot);
       _alpha4->writeDigitAscii(cur_idx, ch, display_dot);
       cur_idx++;
     }

src/components/i2c/drivers/drvOutputBase.h

@@ -87,6 +87,20 @@ class drvOutputBase : public drvBase {
     // noop
   }
 
+  /*!
+      @brief    Configures a character LCD.
+      @param    rows
+                  The number of rows in the LCD.
+      @param    cols
+                  The number of columns in the LCD.
+      @param    enable_backlight
+                  True if the backlight is enabled, False otherwise.
+  */
+  virtual void ConfigureCharLcd(uint32_t rows, uint32_t cols,
+                                bool enable_backlight) {
+    // noop
+  }
+
   /*!
       @brief    Sets the brightness of the LED backpack.
       @param    b