diff --git a/latest/Firmware/WiFiAdapter/bsp/bsp.h b/latest/Firmware/WiFiAdapter/bsp/bsp.h
index 11003c4..d7cbf2f 100644
--- a/latest/Firmware/WiFiAdapter/bsp/bsp.h
+++ b/latest/Firmware/WiFiAdapter/bsp/bsp.h
@@ -14,5 +14,6 @@ void bsp_set_uart_rx_cb(uart_rx_cb_t *cb);
 void bsp_set_button_isr_cb(button_isr_cb_t *cb);
 void bsp_set_timer_cb(timer_cb_t *cb);
 void bsp_uart_write(const char *txt);
+int bsp_read_vbat();
 
 #endif
diff --git a/latest/Firmware/WiFiAdapter/bsp/bsp_1_0.c b/latest/Firmware/WiFiAdapter/bsp/bsp_1_0.c
index 4083141..0103106 100644
--- a/latest/Firmware/WiFiAdapter/bsp/bsp_1_0.c
+++ b/latest/Firmware/WiFiAdapter/bsp/bsp_1_0.c
@@ -2,10 +2,14 @@
 #include "nvs_flash.h"
 #include "driver/uart.h"
 #include "driver/gpio.h"
+#include "driver/i2c.h"
 #include "hal/gpio_hal.h"
 #include <string.h>
 #include "freertos/timers.h"
 #include "esp_intr_alloc.h"
+#include <esp_log.h>
+
+#define TAG "bsp"
 
 static uart_rx_cb_t *uart_cb = NULL;
 static button_isr_cb_t *btn_cb = NULL;
@@ -24,6 +28,10 @@ uint8_t dtmp[RD_BUF_SIZE];
 #define GPIO_GREEN_LED      GPIO_NUM_4
 #define GPIO_STM32_RESET_N  GPIO_NUM_12
 #define GPIO_STM32_TX_EN    GPIO_NUM_13
+#define I2C_MASTER_SCL_IO   GPIO_NUM_22               
+#define I2C_MASTER_SDA_IO   GPIO_NUM_21               
+#define I2C_MASTER_FREQ_HZ  100000                   
+#define I2C_ADC_ADDRESS     0x48
 
 void uart_rx_task(void *params)
 {
@@ -106,15 +114,31 @@ void bsp_timer_init()
     xTimerStart(timer_h, 0);
 }
 
+static esp_err_t i2c_master_init(void)
+{
+  i2c_config_t conf = 
+  {
+    .mode = I2C_MODE_MASTER,
+    .sda_io_num = I2C_MASTER_SDA_IO,
+    .sda_pullup_en = GPIO_PULLUP_ENABLE,
+    .scl_io_num = I2C_MASTER_SCL_IO,
+    .scl_pullup_en = GPIO_PULLUP_ENABLE,
+    .master.clk_speed = I2C_MASTER_FREQ_HZ,
+  };
+  
+  esp_err_t err = i2c_param_config(I2C_NUM_0, &conf);
+  if (err != ESP_OK) 
+  {
+    return err;
+  }
+
+  return i2c_driver_install(I2C_NUM_0, I2C_MODE_MASTER, 0, 0, 0);
+}
 
 void bsp_hw_init()
 {
   bsp_uart_init();
 
-  //config_gpio(GPIO_TX_BUTTON, GPIO_MODE_INPUT, false, false);
-  //gpio_set_direction(GPIO_TX_BUTTON, GPIO_MODE_INPUT);
-  //gpio_set_intr_type(GPIO_TX_BUTTON, GPIO_INTR_NEGEDGE);
-
   config_gpio(GPIO_RED_LED, GPIO_MODE_OUTPUT, false, false);
   config_gpio(GPIO_GREEN_LED, GPIO_MODE_OUTPUT, false, false);
   config_gpio(GPIO_STM32_RESET_N, GPIO_MODE_OUTPUT_OD, false, false);
@@ -122,21 +146,15 @@ void bsp_hw_init()
   config_gpio(GPIO_STM32_TX_EN, GPIO_MODE_OUTPUT_OD, false, false);
   gpio_set_level(GPIO_STM32_TX_EN, 1);
 
+  // Force a reset of the STM32 just in case
   gpio_set_level(GPIO_STM32_RESET_N, 0);
   usleep(2000);
   gpio_set_level(GPIO_STM32_RESET_N, 1);
 
-#if 0
-  gpio_set_direction(GPIO_RED_LED, GPIO_MODE_OUTPUT);
-  gpio_set_direction(GPIO_GREEN_LED, GPIO_MODE_OUTPUT);
-
-  gpio_set_level(GPIO_RED_LED, 1);
-  gpio_set_level(GPIO_GREEN_LED, 1);
-#endif
-
-  //gpio_install_isr_service(0);
-  //gpio_isr_handler_add(GPIO_TX_BUTTON, btn_isr, NULL);
   bsp_timer_init();
+  
+  if ( i2c_master_init() != ESP_OK )
+    ESP_LOGE(TAG, "Unable to initialize I2C master 0");
 }
 
 void bsp_reboot()
@@ -144,3 +162,27 @@ void bsp_reboot()
   esp_restart(); 
 }
 
+int bsp_read_vbat()
+{
+  int sum = 0, cnt = 0;
+
+  for ( int i = 0; i < 16; ++i )
+  {
+    uint8_t result[2] = {0};
+    esp_err_t err = i2c_master_read_from_device(I2C_NUM_0, I2C_ADC_ADDRESS, result, sizeof(result), 100/portTICK_PERIOD_MS);
+    if ( err != ESP_OK )
+    {
+      ESP_LOGE(TAG, "Error reading from ADC: %s", esp_err_to_name(err));
+      return -1;
+    }
+    int mV = (result [0] << 8 | result[1]) * 3284 / 4095;
+    //ESP_LOGI(TAG, "ADC reading: %.2x %.2x", result[0], result[1]);
+    sum += mV;
+    ++cnt;
+  }
+
+  int v = sum/cnt * 2; // Voltage is divided by two on the board
+
+  //return mV * 2;
+  return v;
+}
diff --git a/latest/Firmware/WiFiAdapter/main/MaianaWiFiAdapter.c b/latest/Firmware/WiFiAdapter/main/MaianaWiFiAdapter.c
index eca0d4e..91a34c5 100755
--- a/latest/Firmware/WiFiAdapter/main/MaianaWiFiAdapter.c
+++ b/latest/Firmware/WiFiAdapter/main/MaianaWiFiAdapter.c
@@ -18,6 +18,24 @@ void one_sec_timer()
   esp_event_isr_post(MAIANA_EVENT, ONE_SEC_TIMER_EVENT, NULL, 0, NULL);
 }
 
+static int sec_count = 0;
+static float voltage = 0.0f;
+static float alpha = 0.1;
+
+static void one_sec_handler(void *args, esp_event_base_t base, int32_t id, void *data)
+{
+  float v = bsp_read_vbat() / 1000.0f;
+  if ( sec_count == 0 )
+    voltage = v;
+  else
+    voltage = alpha * v + (1.0 - alpha)*v;
+
+  ++sec_count;
+
+  if ( sec_count % 10 == 0 )
+    ESP_LOGI("main", "Battery voltage: %.3f V", voltage);
+}
+
 void reboot_handler(void *args, esp_event_base_t base, int32_t id, void *data)
 {
   sleep(2);
@@ -28,6 +46,8 @@ void app_main(void)
 {
   esp_event_loop_create_default();
   esp_event_handler_register(MAIANA_EVENT, REBOOT_EVENT, reboot_handler, NULL); 
+  esp_event_handler_register(MAIANA_EVENT, ONE_SEC_TIMER_EVENT, one_sec_handler, NULL); 
+  
 
   //sleep(5);
   config_init();
@@ -36,10 +56,10 @@ void app_main(void)
   bsp_set_timer_cb(one_sec_timer);
   bsp_hw_init();
 
-
+  //bsp_read_vbat();
   wifi_start();
   start_httpd();
-  button_init();
+  //button_init();
 
   nmea_gateway_start();