Ported the code to M5Stack Core2 (different display) and removed reboot on disconnect

esphome/owon-b35t-m5stack-core2.yaml

@@ -1,7 +1,7 @@
 substitutions:
-  name: "owon-b35t"
+  name: "owon-b35t-m5stack-core2"
-  friendly_name: "OWON B35T Multimeter"
+  friendly_name: "OWON B35T Multimeter Core2"
-  device_description: "M5Stack Core 1 BLE client for OWON B35T/B35T+ multimeter with local graphical display"
+  device_description: "M5Stack Core2 BLE client for OWON B35T/B35T+ multimeter with local graphical display"
   owon_mac_address: !secret owon_b35t_mac_address
 
 esphome:
@@ -10,17 +10,27 @@ esphome:
   comment: ${device_description}
   min_version: 2024.6.0
   includes:
-    - owon_b35t.h
+    - owon_b35t-m5stack-core2.h
+  on_boot:
+    priority: 850
+    then:
+      - lambda: |-
+          owon_b35t::core2_axp192_init(id(core2_i2c));
   project:
-    name: "custom.owon-b35t-m5stack"
+    name: "custom.owon-b35t-m5stack-core2"
     version: "1.0"
 
 esp32:
-  board: m5stack-core-esp32
+  board: m5stack-core2
+  flash_size: 16MB
   framework:
     type: esp-idf
     advanced:
-      minimum_chip_revision: "3.1"
+      sram1_as_iram: true
+
+psram:
+  mode: quad
+  speed: 80MHz
 
 logger:
   level: INFO
@@ -44,20 +54,21 @@ wifi:
     ssid: "OWON B35T Fallback Hotspot"
     password: !secret fallback_psk
 
-# Disabled to save RAM on the M5Stack Core 1. Re-enable temporarily if Wi-Fi recovery is needed.
+captive_portal:
-# captive_portal:
 
 interval:
   - interval: 10s
     then:
       - lambda: |-
-          ESP_LOGI("mem", "heap free=%u min_free=%u internal_free=%u internal_largest=%u dma_free=%u dma_largest=%u",
+          ESP_LOGI("mem", "heap free=%u min_free=%u internal_free=%u internal_largest=%u dma_free=%u dma_largest=%u psram_free=%u psram_largest=%u",
                    static_cast<unsigned>(esp_get_free_heap_size()),
                    static_cast<unsigned>(esp_get_minimum_free_heap_size()),
                    static_cast<unsigned>(heap_caps_get_free_size(MALLOC_CAP_INTERNAL)),
                    static_cast<unsigned>(heap_caps_get_largest_free_block(MALLOC_CAP_INTERNAL)),
                    static_cast<unsigned>(heap_caps_get_free_size(MALLOC_CAP_DMA)),
-                   static_cast<unsigned>(heap_caps_get_largest_free_block(MALLOC_CAP_DMA)));
+                   static_cast<unsigned>(heap_caps_get_largest_free_block(MALLOC_CAP_DMA)),
+                   static_cast<unsigned>(heap_caps_get_free_size(MALLOC_CAP_SPIRAM)),
+                   static_cast<unsigned>(heap_caps_get_largest_free_block(MALLOC_CAP_SPIRAM)));
 
 esp32_ble_tracker:
   scan_parameters:
@@ -75,22 +86,24 @@ ble_client:
       then:
         - lambda: |-
             owon_meter.on_disconnect();
-        - logger.log:
-            level: WARN
-            format: "OWON BLE meter disconnected; restarting M5Stack to reclaim heap"
-        - delay: 1s
-        - lambda: |-
-            esp_restart();
 
 spi:
   clk_pin: GPIO18
   mosi_pin: GPIO23
-  miso_pin: GPIO19
+
+i2c:
+  id: core2_i2c
+  sda: GPIO21
+  scl: GPIO22
+  scan: true
 
 output:
-  - platform: ledc
+  - platform: template
-    pin: GPIO32
+    type: float
     id: lcd_backlight
+    write_action:
+      - lambda: |-
+          owon_b35t::core2_axp192_set_backlight(state);
 
 light:
   - platform: monochromatic
@@ -173,35 +186,38 @@ font:
       ]
 
 display:
-  - platform: ili9xxx
+  - platform: mipi_spi
     id: lcd
-    model: M5STACK
+    model: M5CORE2
-    cs_pin: GPIO14
-    dc_pin: GPIO27
-    reset_pin: GPIO33
-    invert_colors: true
-    color_palette: 8BIT
-    rotation: 0
     update_interval: 500ms
     lambda: |-
       owon_meter.render(it, id(meter_font));
 
+touchscreen:
+  - platform: ft63x6
+    id: touch
+    display: lcd
+
 binary_sensor:
-  - platform: gpio
+  - platform: touchscreen
     id: button_a
-    pin:
+    touchscreen_id: touch
-      number: GPIO39
+    x_min: 34
-      inverted: true
+    x_max: 74
+    y_min: 212
+    y_max: 240
     internal: true
     on_press:
       then:
         - lambda: |-
             owon_meter.previous_button();
-  - platform: gpio
+  - platform: touchscreen
     id: button_b
-    pin:
+    touchscreen_id: touch
-      number: GPIO38
+    x_min: 108
-      inverted: true
+    x_max: 208
+    y_min: 212
+    y_max: 240
     internal: true
     on_click:
       - min_length: 50ms
@@ -233,11 +249,13 @@ binary_sensor:
                 uint8_t press_type = (owon_meter.selected_button == 1 || owon_meter.selected_button == 5) ? 0x01 : 0x00;
                 std::vector<uint8_t> data = {owon_meter.selected_button, press_type};
                 return data;
-  - platform: gpio
+  - platform: touchscreen
     id: button_c
-    pin:
+    touchscreen_id: touch
-      number: GPIO37
+    x_min: 242
-      inverted: true
+    x_max: 282
+    y_min: 212
+    y_max: 240
     internal: true
     on_press:
       then:
@@ -278,16 +296,16 @@ sensor:
 text_sensor:
   - platform: template
     name: "${friendly_name} Reading"
-    update_interval: 2s
+    update_interval: 1s
     lambda: |-
       return owon_meter.reading_text();
   - platform: template
     name: "${friendly_name} Unit"
-    update_interval: 2s
+    update_interval: 1s
     lambda: |-
       return std::string(owon_meter.scale()) + owon_meter.unit();
   - platform: template
     name: "${friendly_name} Mode"
-    update_interval: 2s
+    update_interval: 1s
     lambda: |-
       return owon_meter.mode_text();

esphome/owon_b35t-m5stack-core2.h

@@ -13,6 +13,7 @@
 #include "esp_heap_caps.h"
 #include "esp_system.h"
 #include "esphome/core/helpers.h"
+#include "esphome/components/i2c/i2c.h"
 #include "esphome/core/log.h"
 #include "esphome/components/display/display.h"
 
@@ -22,6 +23,92 @@ using esphome::Color;
 using esphome::display::Display;
 
 static const char *const TAG = "owon_b35t";
+static const char *const POWER_TAG = "core2_power";
+static constexpr uint8_t AXP192_ADDR = 0x34;
+static esphome::i2c::I2CDevice axp192;
+static bool axp192_ready = false;
+
+static bool axp_write(uint8_t reg, uint8_t value) {
+  if (!axp192_ready) return false;
+  bool ok = axp192.write_byte(reg, value);
+  if (!ok) ESP_LOGW(POWER_TAG, "AXP192 write reg 0x%02X failed", reg);
+  return ok;
+}
+
+static bool axp_read(uint8_t reg, uint8_t *value) {
+  if (!axp192_ready) return false;
+  bool ok = axp192.read_byte(reg, value);
+  if (!ok) ESP_LOGW(POWER_TAG, "AXP192 read reg 0x%02X failed", reg);
+  return ok;
+}
+
+static void axp_update(uint8_t reg, uint8_t clear_mask, uint8_t set_mask) {
+  uint8_t value = 0;
+  if (!axp_read(reg, &value)) return;
+  value = (value & ~clear_mask) | set_mask;
+  axp_write(reg, value);
+}
+
+static uint8_t axp_dc_voltage_data(uint16_t millivolts) {
+  if (millivolts < 700) millivolts = 700;
+  if (millivolts > 3500) millivolts = 3500;
+  return static_cast<uint8_t>((millivolts - 700) / 25) & 0x7F;
+}
+
+static uint8_t axp_ldo_voltage_data(uint16_t millivolts) {
+  if (millivolts < 1800) millivolts = 1800;
+  if (millivolts > 3300) millivolts = 3300;
+  return static_cast<uint8_t>((millivolts - 1800) / 100) & 0x0F;
+}
+
+static void core2_axp192_set_lcd_voltage(uint16_t millivolts) {
+  uint8_t value = 0;
+  axp_read(0x27, &value);
+  axp_write(0x27, (value & 0x80) | axp_dc_voltage_data(millivolts));  // DCDC3, LCD backlight
+}
+
+static void core2_axp192_set_backlight(float brightness) {
+  if (brightness <= 0.0f) {
+    axp_update(0x12, 0x02, 0x00);  // DCDC3 off
+    return;
+  }
+  if (brightness > 1.0f) brightness = 1.0f;
+  uint16_t millivolts = static_cast<uint16_t>(2400 + brightness * 900);
+  core2_axp192_set_lcd_voltage(millivolts);
+  axp_update(0x12, 0x00, 0x02);  // DCDC3 on
+}
+
+static void core2_axp192_init(esphome::i2c::I2CBus *bus) {
+  axp192.set_i2c_bus(bus);
+  axp192.set_i2c_address(AXP192_ADDR);
+  axp192_ready = true;
+  ESP_LOGI(POWER_TAG, "Initializing M5Stack Core2 AXP192 LCD power");
+  axp_update(0x30, 0xF9, 0x02);  // Disable VBUS current limit, preserve bit 2.
+  axp_update(0x92, 0x07, 0x00);  // GPIO1 open-drain output.
+  axp_update(0x93, 0x07, 0x00);  // GPIO2 open-drain output.
+  axp_write(0x35, 0xA2);         // RTC battery charging.
+
+  uint8_t value = 0;
+  axp_read(0x26, &value);
+  axp_write(0x26, (value & 0x80) | axp_dc_voltage_data(3350));  // DCDC1 ESP32 VDD.
+  core2_axp192_set_lcd_voltage(2800);
+
+  uint8_t ldo2 = axp_ldo_voltage_data(3300);
+  uint8_t ldo3 = axp_ldo_voltage_data(2000);
+  axp_write(0x28, (ldo2 << 4) | ldo3);  // LDO2 LCD logic/SD, LDO3 vibrator.
+  axp_update(0x12, 0x00, 0x07);         // Enable DCDC1, DCDC3, LDO2.
+  axp_write(0x82, 0xFF);                // ADCs on.
+  axp_update(0x95, 0x8D, 0x84);         // GPIO4 setup, as M5Core2 library does.
+  axp_write(0x36, 0x4C);                // Power key timing.
+
+  // LCD reset through AXP192 GPIO4.
+  axp_update(0x96, 0x02, 0x00);
+  delay(100);
+  axp_update(0x96, 0x00, 0x02);
+  delay(100);
+
+  core2_axp192_set_backlight(1.0f);
+}
 
 static const uint8_t ACCU_BMP[32] = {
     0b00000000, 0b00000000,