Finish numberstack code UI

dependencies.lock

@@ -66,6 +66,14 @@ dependencies:
       registry_url: https://components.espressif.com/
       type: service
     version: 2.7.0
+  hayschan/autopid_for_esp_idf:
+    component_hash: 
+      abb01ee57353d22df70c27840ddec00b90544540c9a78ec18932737d7fbb7878
+    dependencies: []
+    source:
+      registry_url: https://components.espressif.com/
+      type: service
+    version: 1.0.2
   idf:
     source:
       type: idf
@@ -82,8 +90,9 @@ direct_dependencies:
 - atanisoft/esp_lcd_touch_xpt2046
 - espressif/esp_lcd_ili9341
 - espressif/esp_lvgl_port
+- hayschan/autopid_for_esp_idf
 - idf
 - lvgl/lvgl
-manifest_hash: d2b549f17124d3d38e4add4614fb10956ada1a576e4c5f6a623ea3756bcd3ba5
+manifest_hash: 5e3bb9d0c782ebaa9ecdc3b0310e8f13b698e0fd5071cab2a465725e2a33722b
 target: esp32
 version: 2.0.0

main/CMakeLists.txt

@@ -1,4 +1,4 @@
-idf_component_register(SRCS "spincoat-plater-firmware.c" "dshot_esc_encoder.c" "display.c"
+idf_component_register(SRCS "spincoat-plater-firmware.cpp" "dshot_esc_encoder.c" "display.c" "motor.c" "ui.c"
                     PRIV_REQUIRES esp_driver_rmt esp_driver_gpio esp_driver_uart esp_driver_spi
-                    esp_lcd unity lvgl esp_lvgl_port esp_lcd_touch_xpt2046
+                    esp_lcd unity lvgl esp_lvgl_port esp_lcd_touch_xpt2046 autopid_for_esp_idf
                     INCLUDE_DIRS ".")

main/Kconfig

@@ -1,12 +1,12 @@
 menu "Pin Mapping Configuration"
     config ESC_CTRL_PIN
         int "ESC control GPIO pin"
-        default 22
+        default 18
         help
             This is the pin used for sending DSHOT packets to the ESC.
     config TELEMETRY_RX_PIN
         int "ESC telemetry uart rx pin"
-        default 27
+        default 19
         help
             This is the pin used for receiving UART telemetry from the ESC.
     config TFT_MISO
@@ -39,7 +39,13 @@ menu "Pin Mapping Configuration"
         default 21
         help
             This is the pin for backlight control on the SPI LCD.
-
+    
+    config MOTOR_POLECOUNT
+        int "Pole count of motor driven by ESC"
+        default 6
+        help
+          This is the number of magnetic poles on your motor, which is used to calculate actual RPM
+          from electrical RPM.
 
     config TOUCH_IRQ
         int "SPI touchscreen IRQ pin"

main/display.c

@@ -58,7 +58,6 @@ void touch_driver_read(lv_indev_t * indev, lv_indev_data_t * data) {
     bool touchpad_pressed = esp_lcd_touch_get_coordinates(tp, x, y, strength, &count, 1);
 
     if(touchpad_pressed == true) {
-        //ESP_LOGI(TAG, "Touchpad pressed from LVGL..\n");
         data->point.x = x[0];
         data->point.y = y[0];
         data->state = LV_INDEV_STATE_PRESSED;
@@ -73,8 +72,6 @@ void touch_driver_read(lv_indev_t * indev, lv_indev_data_t * data) {
 static void btn_event_cb(lv_event_t * e) {
     lv_event_code_t code = lv_event_get_code(e);
 
-    //ESP_LOGI(TAG, "Button callback fired.");
-
     if(code == LV_EVENT_CLICKED) {
         ESP_LOGI(TAG, "LVGL button pressed.");
     }
@@ -132,8 +129,8 @@ void init_touchscreen_xpt2046(void) {
     ESP_ERROR_CHECK(esp_lcd_new_panel_io_spi(TOUCH_SPI_HOST, &tp_io_config, &tp_io_handle));
 
     esp_lcd_touch_config_t tp_cfg = {
-        .x_max = TFT_HRES,
+        .x_max = TFT_VRES,
-        .y_max = TFT_VRES,
+        .y_max = TFT_HRES,
         .rst_gpio_num = -1,
         .int_gpio_num = -1,
         .flags = {
@@ -227,7 +224,7 @@ void init_lvgl_display(void) {
         },
         .flags = {
             .buff_dma = false,
-            .swap_bytes = false,
+            .swap_bytes = true,
         }
     };
     disp_handle = lvgl_port_add_disp(&disp_cfg);
@@ -253,5 +250,4 @@ void init_display(void) {
     init_touchscreen_xpt2046();
     init_lvgl_display();
     init_input();
-    lv_example_btn_1();
 }

main/display.h

@@ -11,12 +11,7 @@
 #define TFT_VRES           CONFIG_TFT_VRES
 #define TFT_BPP            CONFIG_TFT_BPP
 
-#define LVGL_BUF_SIZE TFT_VRES * TFT_HRES / 10 * (TFT_BPP / 8)
+#define LVGL_BUF_SIZE ((TFT_VRES * TFT_HRES) / 10) * (TFT_BPP / 8)
-
-/**
- * Draws a test bitmap of stripes of colors to the LCD.
- */
-void test_draw_bitmap(esp_lcd_panel_handle_t panel_handle);
 
 /**
  * Initializes the display TFT and touchscreen.

main/idf_component.yml

@@ -18,3 +18,4 @@ dependencies:
   lvgl/lvgl: ^9.4.0
   espressif/esp_lvgl_port: ^2.3.0
   atanisoft/esp_lcd_touch_xpt2046: ^1.0.2
+  hayschan/autopid_for_esp_idf: ^1.0.2

main/motor.c

@@ -1,45 +1,17 @@
-/*
+#include "motor.h"
- * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
- *
- * SPDX-License-Identifier: Unlicense OR CC0-1.0
- */
 
-#include <inttypes.h>
+#include "driver/spi_common.h"
-
-#include "freertos/FreeRTOS.h"
-#include "freertos/task.h"
-#include "freertos/semphr.h"
-
-#include "unity.h"
-#include "unity_test_runner.h"
-
-#include "esp_log.h"
 #include "driver/rmt_tx.h"
 #include "driver/uart.h"
-#include "driver/gpio.h"
+#include "esp_log.h"
-
-#include "hal/spi_types.h"
-#include "esp_lcd_panel_ops.h"
-#include "driver/spi_common.h"
-#include "esp_lcd_panel_io.h"
-#include "esp_lcd_panel_commands.h"
-#include "esp_lcd_ili9341.h"
 
 #include "dshot_esc_encoder.h"
-#include "display.h"
-
-#if CONFIG_IDF_TARGET_ESP32H2
-#define DSHOT_ESC_RESOLUTION_HZ 32000000 // 32MHz resolution, DSHot protocol needs a relative high resolution
-#else
-#define DSHOT_ESC_RESOLUTION_HZ 40000000 // 40MHz resolution, DSHot protocol needs a relative high resolution
-#endif
 
 #define GPIO_ESC_CTRL CONFIG_ESC_CTRL_PIN
 #define GPIO_ESC_RX   CONFIG_TELEMETRY_RX_PIN
-#define UART_NUM      UART_NUM_2
 #define ESP_INTR_FLAG_DEFAULT        0
 
-static const char *TAG = "spincoat-plater-firmware";
+static const char *TAG = "spincoat-plater-firmware/motor";
 
 static QueueHandle_t uart_queue = NULL;
 const int uart_buffer_size = (1024 * 2);
@@ -53,7 +25,7 @@ rmt_transmit_config_t tx_config = {
 
 dshot_esc_throttle_t throttle = {
     .throttle = 0,
-    .telemetry_req = false, // telemetry is not supported in this example
+    .telemetry_req = false,
 };
 
 /**
@@ -130,9 +102,9 @@ void init_telemetry_uart_rx(void) {
         .rx_flow_ctrl_thresh = 122,
     };
     
-    ESP_ERROR_CHECK(uart_driver_install(UART_NUM, uart_buffer_size, uart_buffer_size, 10, &uart_queue, 0));
+    ESP_ERROR_CHECK(uart_driver_install(ESC_UART_NUM, uart_buffer_size, uart_buffer_size, 10, &uart_queue, 0));
-    ESP_ERROR_CHECK(uart_param_config(UART_NUM, &uart_config));
+    ESP_ERROR_CHECK(uart_param_config(ESC_UART_NUM, &uart_config));
-    ESP_ERROR_CHECK(uart_set_pin(UART_NUM, UART_PIN_NO_CHANGE, GPIO_ESC_RX, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE));
+    ESP_ERROR_CHECK(uart_set_pin(ESC_UART_NUM, UART_PIN_NO_CHANGE, GPIO_ESC_RX, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE));
 }
 
 
@@ -173,56 +145,64 @@ uint8_t get_crc8(uint8_t *Buf, uint8_t BufLen){
  * Parse the KISS telemetry frame and check the crc8
  * TODO: Do more with the data than print it
  */
-void parse_telemetry(void) {
+bool parse_telemetry(esc_telemetry_t * telemetry) {
     uint8_t frame_size = 10;
     uint8_t data[128];
     // get data
-    uint8_t length = uart_read_bytes(UART_NUM, data, frame_size, 100);
+    uint8_t length = uart_read_bytes(ESC_UART_NUM, data, frame_size, 100);
     
-    uart_flush(UART_NUM);
+    uart_flush(ESC_UART_NUM);
+
+    if(length < 10) return false;
 
-    if(length < 10) return;
-    
     // chop out just the payload
     uint8_t payload[128];
     uint8_t payload_length = (frame_size - 1);
     for(uint8_t i = 0; i < payload_length; i++) {
         payload[i] = data[i];
     }
-    
+
     // calculate the crc8
     uint8_t expected_crc8 = get_crc8(payload, payload_length);
     uint8_t received_crc8 = (uint8_t) data[frame_size - 1];
     
-    if(expected_crc8 != received_crc8) return;
+    if(expected_crc8 != received_crc8) return false;
     
-    for(uint8_t i = 0; i < length; i++) {
+    
-        printf("%d - %d\n", i, data[i]);
+    telemetry->temperature = payload[0];
-    }
+    telemetry->voltage     = (payload[1] << 8) + payload[2];
-    printf("--------------------\n");
+    telemetry->current     = (payload[3] << 8) + payload[4];
-    printf("expected: %d\n", expected_crc8);
+    telemetry->consumption = (payload[5] << 8) + payload[6];
-    printf("received: %d\n", received_crc8);
+    telemetry->rpm         = (payload[7] << 8) + payload[8];
-    printf("======================\n");
+    
+
+    return true;
 }
 
-void app_main(void) {
+/**
-    init_display();
+ * Helper function that sets up the RMT, creates the telemetry task, and 
-    
+ * initializes the telemetry UART.
+ */
+void init_motor(void) {
     init_rmt_esc_tx();
     throttle.throttle = 300;
-    
     xTaskCreate(&v_telemetry_packet_func, "v_telemetry_packet_func", 2048, NULL, 1, NULL);
-
     init_telemetry_uart_rx();
-
+}
-    while(1) {
+
-        send_dshot_packet();
+/**
-        
+ * Returns the current throttle value
-        uint8_t length = 0;
+ */
-        ESP_ERROR_CHECK(uart_get_buffered_data_len(UART_NUM, (size_t*)&length));
+uint16_t get_throttle() {
-        
+    return throttle.throttle;
-        if(length >= 10) {
+}
-            parse_telemetry();
+
-        }
+/**
-    }
+ * Updates the throttle value.
+ *
+ * \arg \c throttle The new throttle value between 0-2048
+ */
+
+void update_throttle(uint16_t thr) {
+    throttle.throttle = thr;
 }

main/motor.h

@@ -0,0 +1,35 @@
+#pragma once
+
+#include <inttypes.h>
+#include <stdbool.h>
+
+#if CONFIG_IDF_TARGET_ESP32H2
+#define DSHOT_ESC_RESOLUTION_HZ 32000000 // 32MHz resolution, DSHot protocol needs a relative high resolution
+#else
+#define DSHOT_ESC_RESOLUTION_HZ 40000000 // 40MHz resolution, DSHot protocol needs a relative high resolution
+#endif
+
+#define ESC_UART_NUM      UART_NUM_2
+
+/**
+ * Struct for returning telemetry data
+ */
+typedef struct {
+  uint16_t temperature;
+  uint16_t voltage;
+  uint16_t current;
+  uint16_t consumption;
+  uint16_t rpm;
+} esc_telemetry_t;
+
+void init_rmt_esc_tx(void);
+
+void send_dshot_packet(void);
+
+bool parse_telemetry(esc_telemetry_t * telemetry);
+
+void init_motor(void);
+
+uint16_t get_throttle(void);
+
+void update_throttle(uint16_t throttle);

main/spincoat-plater-firmware.cpp

@@ -0,0 +1,104 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+
+#include <inttypes.h>
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/semphr.h"
+
+#include "esp_log.h"
+#include "driver/uart.h"
+
+#include "esp_lcd_panel_ops.h"
+#include "driver/spi_common.h"
+#include "esp_lcd_panel_io.h"
+#include "esp_lcd_panel_commands.h"
+#include "esp_lcd_ili9341.h"
+#include "lvgl.h"
+
+#include "AutoPID-for-ESP-IDF.h"
+
+extern "C" {
+    #include "dshot_esc_encoder.h"
+    #include "display.h"
+    #include "ui.h"
+    #include "motor.h"
+}
+
+static const char *TAG = "spincoat-plater-firmware";
+
+static double throttle = 0;
+
+static double zero_offset = 100; // Value to offset the throttle by, to skip the
+                                 // command values
+static double OUTPUT_MIN = 0;
+static double OUTPUT_MAX = 1948;
+
+static double RPM_MAX = 250;
+static double BANG_BANG_THRESHOLD = RPM_MAX + 200;
+
+static double KP = 0.015;
+static double KI = 0.8;
+static double KD = 0.0;
+
+static bool motor_running = false;
+
+extern "C" void app_main(void) {
+    srand((unsigned int)esp_timer_get_time());
+
+    esc_telemetry_t telemetry;
+    double target = 100;
+    double real_rpm = 0;
+
+    AutoPID myPID(&real_rpm, &target, &throttle, OUTPUT_MIN, OUTPUT_MAX, KP, KI, KD);
+    myPID.setTimeStep(100);
+    myPID.setBangBang(400); // if you mess with this, you may melt your circuit
+
+    init_display();
+
+    vTaskDelay(pdMS_TO_TICKS(100));
+    build_ui();
+
+    init_motor();
+    update_throttle(throttle);
+
+    while(1) {
+        send_dshot_packet();
+        
+        uint8_t length = 0;
+        ESP_ERROR_CHECK(uart_get_buffered_data_len(ESC_UART_NUM, (size_t*)&length));
+        
+        if(length >= 10) {
+            if(parse_telemetry(&telemetry)) {
+                
+                real_rpm = telemetry.rpm / (uint16_t) CONFIG_MOTOR_POLECOUNT;
+
+                myPID.run();
+                update_throttle(throttle + zero_offset);
+
+                update_rpm_readout(real_rpm);
+                ESP_LOGI(TAG, "eRPM: %d, RPM: %.2f, SetPoint: %.2f, Output: %.2f",
+                    telemetry.rpm,
+                    real_rpm,
+                    target,
+                    throttle + zero_offset); // Log the values
+
+                if(myPID.atSetPoint(10)) {
+                    ESP_LOGI(TAG, "At setpoint.");
+                }
+
+                vTaskDelay(pdMS_TO_TICKS(100));
+
+                if(real_rpm >= 30) {
+                  motor_running = true;
+                } else {
+                  motor_running = false;
+                }
+            }
+        }
+    }
+}

main/ui.c

@@ -0,0 +1,217 @@
+#include "ui.h"
+
+// #include "lv_font.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+
+#include "motor.h"
+
+#define BTN_INCREMENT 100
+
+#define MAX_RPM_SETTING 200
+#define MAX_COAT_TIME_SETTING 30
+
+#define MIN_RPM_SETTING 50
+#define MIN_COAT_TIME_SETTING 5
+
+#define RPM_STEPSIZE 25
+#define COAT_TIME_STEPSIZE 5
+
+static const char *TAG = "spincoat-plater-firmware/ui";
+
+static lv_obj_t * rpm_label = NULL;
+static lv_obj_t * coat_time_label = NULL;
+static lv_obj_t * run_stop_label = NULL;
+
+static uint16_t rpm_setting = 100; // rpm
+static uint16_t coat_time_setting = 5; // seconds
+
+static coat_state motor_state = STOPPED;
+
+/**
+ * Callback for pressing the rpm increase button
+ */
+void rpm_increase_cb(lv_event_t * e) {
+    ESP_LOGI(TAG, "RPM increase callback called.");
+    if(rpm_setting < MAX_RPM_SETTING) {
+      rpm_setting += RPM_STEPSIZE;
+      lv_lock();
+      lv_label_set_text_fmt(rpm_label, "%d", rpm_setting);
+      lv_unlock();
+    }
+}
+
+/**
+ * Callback for pressing the rpm decrease button
+ */
+void rpm_decrease_cb(lv_event_t * e) {
+    ESP_LOGI(TAG, "RPM decrease callback called.");
+    if(rpm_setting > MIN_RPM_SETTING) {
+      rpm_setting -= RPM_STEPSIZE;
+      lv_lock();
+      lv_label_set_text_fmt(rpm_label, "%d", rpm_setting);
+      lv_unlock();
+    }
+
+}
+
+/**
+ * Callback for pressing the coat time increase button
+ */
+
+void coat_increase_cb(lv_event_t * e) {
+    ESP_LOGI(TAG, "Coat time increase callback called.");
+    if(coat_time_setting < MAX_COAT_TIME_SETTING) {
+        coat_time_setting += COAT_TIME_STEPSIZE;
+        lv_lock();
+        lv_label_set_text_fmt(coat_time_label, "%d", coat_time_setting);
+        lv_unlock();
+    }
+}
+
+/**
+ * Callback for pressing the coat time decrease button
+ */
+void coat_decrease_cb(lv_event_t * e) {
+    ESP_LOGI(TAG, "Coat time decrease callback called.");
+    if(coat_time_setting > MIN_COAT_TIME_SETTING) {
+        coat_time_setting -= COAT_TIME_STEPSIZE;
+        lv_lock();
+        lv_label_set_text_fmt(coat_time_label, "%d", coat_time_setting);
+        lv_unlock();
+    }
+}
+
+void run_stop_cb(lv_event_t * e) {
+    ESP_LOGI(TAG, "Run/stop callback called.");
+    if(run_stop_label == NULL) return;
+    lv_label_set_text(run_stop_label, "Stop");
+}
+
+
+/**
+ * Factory function that creates a "numberstack" widget and returns the label for it
+ */
+lv_obj_t * build_numberstack(lv_obj_t * parent,
+        const char * label_text,
+        lv_obj_t ** label_value,
+        ns_btn_cb_t top_btn_cb,
+        ns_btn_cb_t bottom_btn_cb,
+        uint16_t start_value,
+        uint16_t stepsize) {
+
+    lv_obj_t * container = lv_obj_create(parent);
+    lv_obj_set_flex_flow(container, LV_FLEX_FLOW_COLUMN);
+    lv_obj_set_flex_align(container,
+            LV_FLEX_ALIGN_START,
+            LV_FLEX_ALIGN_CENTER,
+            LV_FLEX_ALIGN_CENTER);
+
+    lv_obj_set_style_pad_all(container, 0, 0);
+
+    /* -------- Top label -------- */
+    lv_obj_t * label_cont = lv_obj_create(container);
+
+    lv_obj_remove_flag(label_cont, LV_OBJ_FLAG_SCROLLABLE);
+
+    lv_obj_set_flex_grow(label_cont, 1);
+    lv_obj_set_width(label_cont, lv_pct(100));
+
+    lv_obj_t * label = lv_label_create(label_cont);
+    lv_label_set_text(label, label_text);
+
+    lv_obj_set_style_bg_opa(label, LV_OPA_COVER, 0);
+
+    lv_obj_set_style_text_font(label, &lv_font_montserrat_12, 0);
+    lv_obj_center(label);
+    
+    /* -------- Top button -------- */
+    lv_obj_t * btn_top = lv_button_create(container);
+    lv_obj_t * lbl_top = lv_label_create(btn_top);
+    lv_label_set_text_fmt(lbl_top, "+%d", stepsize);
+    lv_obj_add_event_cb(btn_top, top_btn_cb, LV_EVENT_CLICKED, (void *) 1);
+    lv_obj_set_flex_grow(btn_top, 1);
+    lv_obj_set_width(btn_top, lv_pct(100));
+    lv_obj_center(lbl_top);
+
+    /* -------- Center label -------- */
+    lv_obj_t * label2_cont = lv_obj_create(container);
+    
+    lv_obj_remove_flag(label2_cont, LV_OBJ_FLAG_SCROLLABLE);
+
+    lv_obj_set_flex_grow(label2_cont, 1);
+    lv_obj_set_width(label2_cont, lv_pct(100));
+
+    * label_value = lv_label_create(label2_cont);
+    lv_label_set_text_fmt(*label_value, "%d", start_value);
+
+    lv_obj_set_style_bg_opa(*label_value, LV_OPA_COVER, 0);
+
+    lv_obj_set_style_text_font(*label_value, &lv_font_montserrat_12, 0);
+    lv_obj_center(*label_value);
+
+    /* -------- Bottom button -------- */
+    lv_obj_t * btn_bottom = lv_button_create(container);
+    lv_obj_t * lbl_bottom = lv_label_create(btn_bottom);
+    lv_label_set_text_fmt(lbl_bottom, "-%d", stepsize);
+    lv_obj_add_event_cb(btn_bottom, bottom_btn_cb, LV_EVENT_CLICKED, (void *) 2);
+    lv_obj_set_flex_grow(btn_bottom, 1);
+    lv_obj_set_width(btn_bottom, lv_pct(100));
+    lv_obj_center(lbl_bottom);
+    
+    return container;
+}
+
+void update_rpm_readout(uint16_t rpm) {
+    if(rpm_label != NULL) {
+        lv_label_set_text_fmt(rpm_label, "RPM: %d", rpm);
+    }
+};
+
+void build_ui(void) {
+    lv_obj_t * container = lv_obj_create(lv_screen_active());
+    lv_obj_set_size(container, lv_pct(100), lv_pct(100));
+    lv_obj_set_flex_flow(container, LV_FLEX_FLOW_COLUMN);
+    lv_obj_set_flex_align(container,
+            LV_FLEX_ALIGN_START,
+            LV_FLEX_ALIGN_CENTER,
+            LV_FLEX_ALIGN_CENTER);
+
+    lv_obj_t * numberstacks_container = lv_obj_create(container);
+    lv_obj_set_size(numberstacks_container , lv_pct(100), lv_pct(70));
+    lv_obj_set_flex_flow(numberstacks_container, LV_FLEX_FLOW_ROW);
+    lv_obj_set_flex_align(numberstacks_container,
+            LV_FLEX_ALIGN_SPACE_EVENLY,
+            LV_FLEX_ALIGN_CENTER,
+            LV_FLEX_ALIGN_CENTER);
+
+    lv_obj_t * rpm_container = build_numberstack(numberstacks_container, "RPM", &rpm_label,
+        rpm_increase_cb, rpm_decrease_cb, rpm_setting, RPM_STEPSIZE);
+    lv_obj_t * coat_time_container = build_numberstack(numberstacks_container, "Coat Time",
+        &coat_time_label, coat_increase_cb, coat_decrease_cb, coat_time_setting, COAT_TIME_STEPSIZE);
+
+    lv_obj_set_size(rpm_container, lv_pct(48), lv_pct(96));
+    lv_obj_set_size(coat_time_container, lv_pct(48), lv_pct(96));
+
+    lv_obj_set_style_pad_all(container, 0, 0);
+    lv_obj_set_style_pad_all(numberstacks_container, 0, 0);
+    lv_obj_set_style_pad_all(rpm_container, 0, 0);
+    lv_obj_set_style_pad_all(coat_time_container, 0, 0);
+
+    /* -------- Run/Stop button -------- */
+    lv_obj_t * btn_run_stop = lv_button_create(container);
+    lv_obj_t * lbl_run_stop = lv_label_create(btn_run_stop);
+
+    run_stop_label = lbl_run_stop;
+
+    lv_label_set_text(lbl_run_stop, "Run");
+
+    lv_obj_center(lbl_run_stop);
+
+    lv_obj_add_event_cb(btn_run_stop, run_stop_cb, LV_EVENT_CLICKED, NULL);
+
+    lv_obj_set_size(btn_run_stop, lv_pct(96), lv_pct(18));
+    lv_obj_set_style_pad_all(btn_run_stop, 0, 0);
+}
+

main/ui.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include "lvgl.h"
+
+#include "motor.h"
+
+/** Numberstack button callback type */
+typedef void (*ns_btn_cb_t)(lv_event_t *);
+
+typedef struct {
+    ns_btn_cb_t top_cb;
+    ns_btn_cb_t bottom_cb;
+} ns_widget_ctx_t; /** Numberstack widget context type */
+
+typedef enum {
+  STOPPED,
+  SPINUP,
+  COATING,
+  SPINDOWN
+} coat_state;
+
+lv_obj_t * build_numberstack(lv_obj_t * parent,
+        const char * label_text,
+        lv_obj_t ** label_value,
+        ns_btn_cb_t top_btn_cb,
+        ns_btn_cb_t bottom_btn_cb,
+        uint16_t start_value,
+        uint16_t stepsize);
+
+void update_rpm_readout(uint16_t rpm);
+
+void build_ui(void);
+