M5 battery monitor improved (read IP5306 chip)

include/power.h

@@ -36,28 +36,40 @@ void AXP192_showstatus(void);
 
 #endif // HAS_PMU
 
+#ifdef HAS_IP5306
+void printIP5306Stats(void);
+uint8_t IP5306_GetPowerSource(void);
+uint8_t IP5306_GetBatteryLevel(void);
+uint8_t IP5306_GetBatteryFull(void);
+#endif
+
 // The following map functions were taken from
 //
 // Battery.h - Battery library
 // Copyright (c) 2014 Roberto Lo Giacco
 // https://github.com/rlogiacco/BatterySense
- 
+
 /**
  * Symmetric sigmoidal approximation
  * https://www.desmos.com/calculator/7m9lu26vpy
  *
  * c - c / (1 + k*x/v)^3
  */
-static inline uint8_t sigmoidal(uint16_t voltage, uint16_t minVoltage, uint16_t maxVoltage) {
+static inline uint8_t sigmoidal(uint16_t voltage, uint16_t minVoltage,
-	// slow
+                                uint16_t maxVoltage) {
-	// uint8_t result = 110 - (110 / (1 + pow(1.468 * (voltage - minVoltage)/(maxVoltage - minVoltage), 6)));
+  // slow
+  // uint8_t result = 110 - (110 / (1 + pow(1.468 * (voltage -
+  // minVoltage)/(maxVoltage - minVoltage), 6)));
 
-	// steep
+  // steep
-	// uint8_t result = 102 - (102 / (1 + pow(1.621 * (voltage - minVoltage)/(maxVoltage - minVoltage), 8.1)));
+  // uint8_t result = 102 - (102 / (1 + pow(1.621 * (voltage -
+  // minVoltage)/(maxVoltage - minVoltage), 8.1)));
 
-	// normal
+  // normal
-	uint8_t result = 105 - (105 / (1 + pow(1.724 * (voltage - minVoltage)/(maxVoltage - minVoltage), 5.5)));
+  uint8_t result = 105 - (105 / (1 + pow(1.724 * (voltage - minVoltage) /
-	return result >= 100 ? 100 : result;
+                                             (maxVoltage - minVoltage),
+                                         5.5)));
+  return result >= 100 ? 100 : result;
 }
 
 /**
@@ -66,9 +78,13 @@ static inline uint8_t sigmoidal(uint16_t voltage, uint16_t minVoltage, uint16_t
  *
  * c - c / [1 + (k*x/v)^4.5]^3
  */
-static inline uint8_t asigmoidal(uint16_t voltage, uint16_t minVoltage, uint16_t maxVoltage) {
+static inline uint8_t asigmoidal(uint16_t voltage, uint16_t minVoltage,
-	uint8_t result = 101 - (101 / pow(1 + pow(1.33 * (voltage - minVoltage)/(maxVoltage - minVoltage) ,4.5), 3));
+                                 uint16_t maxVoltage) {
-	return result >= 100 ? 100 : result;
+  uint8_t result = 101 - (101 / pow(1 + pow(1.33 * (voltage - minVoltage) /
+                                                (maxVoltage - minVoltage),
+                                            4.5),
+                                    3));
+  return result >= 100 ? 100 : result;
 }
 
 /**
@@ -77,8 +93,10 @@ static inline uint8_t asigmoidal(uint16_t voltage, uint16_t minVoltage, uint16_t
  *
  * x * 100 / v
  */
-static inline uint8_t linear(uint16_t voltage, uint16_t minVoltage, uint16_t maxVoltage) {
+static inline uint8_t linear(uint16_t voltage, uint16_t minVoltage,
-	return (unsigned long)(voltage - minVoltage) * 100 / (maxVoltage - minVoltage);
+                             uint16_t maxVoltage) {
+  return (unsigned long)(voltage - minVoltage) * 100 /
+         (maxVoltage - minVoltage);
 }
 
 uint8_t read_battlevel(mapFn_t mapFunction = &sigmoidal);

src/cyclic.cpp

@@ -65,12 +65,14 @@ void doHousekeeping() {
 #endif
 
 // read battery voltage into global variable
-#if (defined BAT_MEASURE_ADC || defined HAS_PMU)
+#if (defined BAT_MEASURE_ADC || defined HAS_PMU || defined HAS_IP5306)
   batt_level = read_battlevel();
-  ESP_LOGI(TAG, "Battery: %d%%", batt_level);
 #ifdef HAS_PMU
   AXP192_showstatus();
 #endif
+#ifdef HAS_IP5306
+  printIP5306Stats();
+#endif
 #endif
 
 // display BME680/280 sensor data

src/display.cpp

@@ -280,7 +280,7 @@ void dp_drawPage(time_t t, bool nextpage) {
 
     // line 4: Battery + GPS status + Wifi channel
     // B:a.bcV Sats:ab ch:ab
-#if (defined BAT_MEASURE_ADC || defined HAS_PMU)
+#if (defined BAT_MEASURE_ADC || defined HAS_PMU || defined HAS_IP5306)
     if (batt_level == 0)
       dp_printf("No batt ");
     else if (batt_level < 100)
@@ -290,6 +290,7 @@ void dp_drawPage(time_t t, bool nextpage) {
 #else
     dp_printf("       ");
 #endif
+
 #if (HAS_GPS)
     dp_setFont(MY_FONT_SMALL, !gps_hasfix());
     dp_printf("Sats:%.2d", gps.satellites.value());

src/hal/m5core.h

@@ -34,12 +34,12 @@
 
 #define HAS_DISPLAY 2 // TFT-LCD, support work in progess, not ready yet
 //#define MY_DISPLAY_FLIP  1 // use if display is rotated
-//#define BAT_MEASURE_ADC ADC1_GPIO35_CHANNEL // battery probe GPIO pin -> ADC1_CHANNEL_7
-//#define BAT_VOLTAGE_DIVIDER 2 // voltage divider 100k/100k on board
 
 #define HAS_LED NOT_A_PIN // no on board LED (?)
 #define HAS_BUTTON (39) // on board button A
 
+#define HAS_IP5306 1
+
 // GPS settings
 #define HAS_GPS 1 // use on board GPS
 #define GPS_SERIAL 9600, SERIAL_8N1, RXD2, TXD2 // UBlox NEO 6M RX, TX

src/hal/m5fire.h

@@ -34,8 +34,6 @@
 
 #define HAS_DISPLAY 2 // TFT-LCD, support work in progess, not ready yet
 //#define MY_DISPLAY_FLIP  1 // use if display is rotated
-//#define BAT_MEASURE_ADC ADC1_GPIO35_CHANNEL // battery probe GPIO pin -> ADC1_CHANNEL_7
-//#define BAT_VOLTAGE_DIVIDER 2 // voltage divider 100k/100k on board
 
 #define HAS_LED NOT_A_PIN // no on board LED (?)
 #define RGB_LED_COUNT 10
@@ -43,6 +41,8 @@
 #define HAS_RGB_LED SmartLed rgb_led(LED_SK6812, RGB_LED_COUNT, GPIO_NUM_15) // LED_SK6812 RGB LED on GPIO15
 #define HAS_BUTTON (39) // on board button A
 
+#define HAS_IP5306 1
+
 // GPS settings
 #define HAS_GPS 0 // use on board GPS
 #define GPS_SERIAL 9600, SERIAL_8N1, RXD2, TXD2 // UBlox NEO 6M RX, TX

src/lorawan.cpp

@@ -492,6 +492,9 @@ uint8_t myBattLevelCb(void *pUserData) {
 #ifdef HAS_PMU
       if (pmu.isVBUSPlug())
     lmic_batt_level = MCMD_DEVS_EXT_POWER;
+#elif defined HAS_IP5306
+      if (IP5306_GetPowerSource())
+    lmic_batt_level = MCMD_DEVS_EXT_POWER;
 #else
       if (batt_percent >= 100)
     lmic_batt_level = MCMD_DEVS_EXT_POWER;

src/main.cpp

@@ -258,10 +258,13 @@ void setup() {
 #endif
 
 // initialize battery status
-#if (defined BAT_MEASURE_ADC || defined HAS_PMU)
+#if (defined BAT_MEASURE_ADC || defined HAS_PMU || defined HAS_IP5306)
   strcat_P(features, " BATT");
   calibrate_voltage();
   batt_level = read_battlevel();
+#ifdef HAS_IP5306
+  printIP5306Stats();
+#endif
 #endif
 
 #if (USE_OTA)

src/power.cpp

@@ -215,6 +215,10 @@ uint8_t read_battlevel(mapFn_t mapFunction) {
   // returns the estimated battery level in values 0 ... 100 [percent]
 
   uint8_t batt_percent;
+
+#ifdef HAS_IP5306
+  batt_percent = IP5306_GetBatteryLevel();
+#else
   const uint16_t batt_voltage = read_voltage();
 
   if (batt_voltage <= BAT_MIN_VOLTAGE)
@@ -224,17 +228,88 @@ uint8_t read_battlevel(mapFn_t mapFunction) {
   else
     batt_percent =
         (*mapFunction)(batt_voltage, BAT_MIN_VOLTAGE, BAT_MAX_VOLTAGE);
-
+#endif // HAS_IP5306
-  ESP_LOGD(TAG, "batt_voltage = %dmV / batt_percent = %d%%", batt_voltage,
-           batt_percent);
 
   return batt_percent;
 }
 
 bool batt_sufficient() {
-#if (defined HAS_PMU || defined BAT_MEASURE_ADC)
+#if (defined HAS_PMU || defined BAT_MEASURE_ADC || defined HAS_IP5306)
   return (batt_level > OTA_MIN_BATT);
 #else
   return true; // we don't know batt level
 #endif
 }
+
+#ifdef HAS_IP5306
+
+// IP5306 code snippet was taken from
+// https://gist.github.com/me-no-dev/7702f08dd578de5efa47caf322250b57
+
+#define IP5306_REG_SYS_0 0x00
+#define IP5306_REG_SYS_1 0x01
+#define IP5306_REG_SYS_2 0x02
+#define IP5306_REG_CHG_0 0x20
+#define IP5306_REG_CHG_1 0x21
+#define IP5306_REG_CHG_2 0x22
+#define IP5306_REG_CHG_3 0x23
+#define IP5306_REG_CHG_4 0x24
+#define IP5306_REG_READ_0 0x70
+#define IP5306_REG_READ_1 0x71
+#define IP5306_REG_READ_2 0x72
+#define IP5306_REG_READ_3 0x77
+#define IP5306_REG_READ_4 0x78
+
+#define IP5306_LEDS2PCT(byte)                                                  \
+  ((byte & 0x01 ? 25 : 0) + (byte & 0x02 ? 25 : 0) + (byte & 0x04 ? 25 : 0) +  \
+   (byte & 0x08 ? 25 : 0))
+
+uint8_t ip5306_get_bits(uint8_t reg, uint8_t index, uint8_t bits) {
+  uint8_t value;
+  if (i2c_readBytes(0x75, reg, &value, 1) == 0xff) {
+    ESP_LOGW(TAG, "IP5306 get bits fail: 0x%02x", reg);
+    return 0;
+  }
+  return (value >> index) & ((1 << bits) - 1);
+}
+
+void ip5306_set_bits(uint8_t reg, uint8_t index, uint8_t bits, uint8_t value) {
+  uint8_t mask = (1 << bits) - 1, v;
+  if (i2c_readBytes(0x75, reg, &v, 1) == 0xff) {
+    ESP_LOGW(TAG, "IP5306 register read fail: 0x%02x", reg);
+    return;
+  }
+  v &= ~(mask << index);
+  v |= ((value & mask) << index);
+
+  if (i2c_writeBytes(0x75, reg, &v, 1) == 0xff)
+    ESP_LOGW(TAG, "IP5306 register write fail: 0x%02x", reg);
+}
+
+uint8_t IP5306_GetPowerSource(void) {
+  ip5306_get_bits(IP5306_REG_READ_0, 3, 1); // 0:BAT, 1:VIN
+}
+
+uint8_t IP5306_GetBatteryFull(void) {
+  ip5306_get_bits(IP5306_REG_READ_1, 3, 1); // 0:CHG/DIS, 1:FULL
+}
+
+uint8_t IP5306_GetBatteryLevel(void) {
+  uint8_t state = (~ip5306_get_bits(IP5306_REG_READ_4, 4, 4)) & 0x0F;
+  // LED[0-4] State (inverted)
+  return IP5306_LEDS2PCT(state);
+}
+
+void printIP5306Stats(void) {
+  bool usb = IP5306_GetPowerSource();
+  bool full = IP5306_GetBatteryFull();
+  uint8_t leds = IP5306_GetBatteryLevel();
+  ESP_LOGI(TAG,
+           "IP5306: Power Source: %s, Battery State: %s, Battery "
+           "Level: %u%%",
+           usb ? "USB" : "BATTERY",
+           full ? "CHARGED" : (usb ? "CHARGING" : "DISCHARGING"),
+           IP5306_LEDS2PCT(leds));
+}
+
+#endif // HAS_IP5306