Fix 3.5" backlight to GPIO27 and document CYD board pitfalls.

Align cyd_35r with 3248S035C pinout (BL!=INT) and point to CYD_PROJECT_GUIDE. Co-authored-by: Cursor <cursoragent@cursor.com>
2026-10-25 10:38:23 +08:00
parent 0a58ed8a79
commit 71fde27f05
5 changed files with 217 additions and 26 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog

+## 2026-10-25 — 3.5" backlight pin correction
+
+- `cyd_35r`: `TFT_BL` / `TFT_BL_PIN` **GPIO27** (was wrongly 21; 21 is GT911 INT).
+- Document board pitfalls in `../CYD_PROJECT_GUIDE.md` §1.1.
+
 ## 2026-10-18 — Pomodoro presets + custom minutes

 - Duration presets: 1 / 3 / 5 / 10 minutes; `Set` opens numeric keypad (1–99).
--- a/README.md
+++ b/README.md
@@ -1,10 +1,13 @@
 # CYD Pomodoro

-ESP32-2432S028R：LVGL 横屏番茄钟，可选内置提示音，触控喇叭播放。
+默认板：**ESP32-2432S028R**（2.8"）：LVGL 横屏番茄钟，可选内置提示音，触控喇叭播放。
+
+可选 **3.5"**：`pio run -e cyd_35r`（ST7796 + GT911，背光 **GPIO27**）。  
+跨板约定与避坑见上级目录 [`../CYD_PROJECT_GUIDE.md`](../CYD_PROJECT_GUIDE.md)（§1.1）。

 ## 功能

- SoftSPI 触摸（已标定，勿改 `src/touch.cpp` 映射）
+- SoftSPI 触摸（2.8，已标定，勿改 `src/touch.cpp` 映射）；3.5C 为 GT911 I2C
 - 番茄钟：预设 1 / 3 / 5 / 10 分钟；`Set` 自定义输入；`+/-` 微调；Start / Pause / Reset
 - 结束音效：内置 Beep 列表自选（默认 Alarm），点名称可试听
 - 喇叭 GPIO26 + 音量滑条；TF 卡状态显示在右上角
@@ -13,10 +16,13 @@ ESP32-2432S028R：LVGL 横屏番茄钟，可选内置提示音，触控喇叭播
 ## 构建 / 烧录

 ```bash
+# 2.8"
 pio run -e cyd -t upload --upload-port COM3
+# 3.5" 电容板
+pio run -e cyd_35r -t upload --upload-port COM3
 ```

-或 `firmware/cyd/flash.bat`。
+或 `firmware/cyd/flash.bat`（2.8 预编译包）。

 浏览器刷写（推荐）：在 [`../cydweb`](../cydweb) 运行 `npm run dev`，打开 http://localhost:3000 ，选择 **CYD Pomodoro**。

--- a/include/pins.h
+++ b/include/pins.h
@@ -8,19 +8,25 @@
 #define SCREEN_HEIGHT 480
 #define UI_HOR_RES    480
 #define UI_VER_RES    320
+/* 3.5C capacitive GT911 (ESP32-3248S035C). GPIO33 is I2C SDA, not TOUCH_CS.
+ * Backlight is GPIO27; INT is GPIO21 — they are NOT the same pin. */
+#define CYD_GT911_SDA  33
+#define CYD_GT911_SCL  32
+#define CYD_GT911_INT  21
+#define CYD_GT911_RST  25
 #else
 #define TFT_BL_PIN 21
 #define SCREEN_WIDTH  240
 #define SCREEN_HEIGHT 320
 #define UI_HOR_RES    320
 #define UI_VER_RES    240
-#endif
-
+/* 2.8" CYD: dedicated SoftSPI touch bus. */
 #define CYD_TOUCH_IRQ  36
 #define CYD_TOUCH_MOSI 32
 #define CYD_TOUCH_MISO 39
 #define CYD_TOUCH_CLK  25
 #define CYD_TOUCH_CS   33
+#endif

 /* Map 320x240 design coordinates onto the active UI resolution (identity on 2.8"). */
 #define UX(x) ((int)(((long)(x) * (UI_HOR_RES)) / 320))
@@ -28,6 +34,13 @@
 #define UW(w) UX(w)
 #define UH(h) UY(h)

+/* Partial frame buffer: 3.5 needs smaller ratio to fit DRAM. */
+#if defined(CYD_BOARD_3248S035)
+#define DRAW_BUF_DIV 20
+#else
+#define DRAW_BUF_DIV 10
+#endif
+

 #define SD_MISO 19
 #define SD_MOSI 23
--- a/platformio.ini
+++ b/platformio.ini
@@ -54,19 +54,27 @@ build_flags =

 extra_scripts = pre:copy_lv_conf.py

-; Optional 3.5" CYD ESP32-3248S035 (ST7796 resistive). Default remains [env:cyd].
+; Optional 3.5" CYD ESP32-3248S035C (ST7796 + GT911 capacitive). Default [env:cyd].
 ; Build: pio run -e cyd_35r
+; Keep TOUCH_CS=-1 — GPIO33 is GT911 SDA, not resistive touch CS.
+; TFT_BL=GPIO27 (not 21 — 21 is GT911 INT). See ../CYD_PROJECT_GUIDE.md §1.1
 [env:cyd_35r]
 extends = env:cyd
+build_unflags =
+  -DILI9341_2_DRIVER=1
+  -DTFT_WIDTH=240
+  -DTFT_HEIGHT=320
+  -DTFT_BL=21
+  -DLV_MEM_SIZE=49152
 build_flags =
  ${env:cyd.build_flags}
-  -UILI9341_2_DRIVER
  -DST7796_DRIVER=1
-  -UTFT_WIDTH
-  -UTFT_HEIGHT
  -DTFT_WIDTH=320
  -DTFT_HEIGHT=480
-  -UTFT_BL
  -DTFT_BL=27
  -DCYD_BOARD_3248S035=1
+  -DUSE_HSPI_PORT
+  -DSUPPORT_TRANSACTIONS
+  -DTFT_RGB_ORDER=TFT_BGR
+  -DLV_MEM_SIZE=32768

--- a/src/touch.cpp
+++ b/src/touch.cpp
@@ -3,10 +3,13 @@

 #include <Arduino.h>

+#if defined(CYD_BOARD_3248S035)
+#include <Wire.h>
+#endif
+
 /**
- * SoftSPI XPT2046
- * BL↔TR 是矩形主对角线镜像（XY 对调），不是 180°（180° 会搞成 TL↔BR）。
- * 先按 rot2 得到旧 UI，再做对角修正，反变换喂给 LVGL 270。
+ * 2.8": dedicated SoftSPI + BL/TR diagonal fix.
+ * 3.5C (3248S035C): capacitive GT911 on I2C SDA33/SCL32/INT21/RST25.
 */

 int16_t g_dbg_phys_x = -1;
@@ -15,6 +18,173 @@ int16_t g_dbg_logic_x = -1;
 int16_t g_dbg_logic_y = -1;
 bool g_dbg_touch_down = false;

+static int16_t clampi(int32_t v, int32_t lo, int32_t hi) {
+  if (v < lo) {
+    return (int16_t)lo;
+  }
+  if (v > hi) {
+    return (int16_t)hi;
+  }
+  return (int16_t)v;
+}
+
+#if defined(CYD_BOARD_3248S035)
+
+/* Minimal GT911 — no config rewrite (TAMC setResolution can hang Wire). */
+static uint8_t s_gt_addr = 0x5D;
+static constexpr uint16_t GT_POINT_INFO = 0x814E;
+static constexpr uint16_t GT_POINT_1 = 0x814F;
+
+static bool gt_write8(uint16_t reg, uint8_t val) {
+  Wire.beginTransmission(s_gt_addr);
+  Wire.write((uint8_t)(reg >> 8));
+  Wire.write((uint8_t)(reg & 0xFF));
+  Wire.write(val);
+  return Wire.endTransmission() == 0;
+}
+
+static bool gt_read(uint16_t reg, uint8_t *buf, uint8_t len) {
+  Wire.beginTransmission(s_gt_addr);
+  Wire.write((uint8_t)(reg >> 8));
+  Wire.write((uint8_t)(reg & 0xFF));
+  if (Wire.endTransmission(false) != 0) {
+    return false;
+  }
+  const uint8_t n = Wire.requestFrom(s_gt_addr, len);
+  if (n != len) {
+    return false;
+  }
+  for (uint8_t i = 0; i < len; i++) {
+    buf[i] = Wire.read();
+  }
+  return true;
+}
+
+static bool gt_probe(uint8_t addr) {
+  Wire.beginTransmission(addr);
+  return Wire.endTransmission() == 0;
+}
+
+/* TAMC-compatible address select: INT low => 0x5D, INT high => 0x14 */
+static void gt_hw_reset(bool addr_0x14) {
+  pinMode(CYD_GT911_INT, OUTPUT);
+  pinMode(CYD_GT911_RST, OUTPUT);
+  digitalWrite(CYD_GT911_INT, LOW);
+  digitalWrite(CYD_GT911_RST, LOW);
+  delay(10);
+  digitalWrite(CYD_GT911_INT, addr_0x14 ? HIGH : LOW);
+  delay(1);
+  digitalWrite(CYD_GT911_RST, HIGH);
+  delay(5);
+  digitalWrite(CYD_GT911_INT, LOW);
+  delay(50);
+  /* Backlight is GPIO27 — leave INT as input for polling / optional IRQ. */
+  pinMode(CYD_GT911_INT, INPUT);
+  delay(50);
+}
+
+static bool gt_find_addr() {
+  for (uint8_t a : {uint8_t(0x5D), uint8_t(0x14)}) {
+    if (gt_probe(a)) {
+      s_gt_addr = a;
+      return true;
+    }
+  }
+  return false;
+}
+
+void touch_init() {
+  Serial.println("Touch: GT911 I2C capacitive (3.5C) minimal");
+  Wire.begin(CYD_GT911_SDA, CYD_GT911_SCL);
+  Wire.setClock(100000);
+#if defined(WIRE_HAS_TIMEOUT) || defined(ESP32)
+  Wire.setTimeOut(50);
+#endif
+
+  if (!gt_find_addr()) {
+    Serial.println("GT911 not found — hw reset 0x5D");
+    gt_hw_reset(false);
+    if (!gt_find_addr()) {
+      Serial.println("GT911 not found — hw reset 0x14");
+      gt_hw_reset(true);
+      gt_find_addr();
+    }
+  }
+
+  Serial.printf("GT911 probe 0x5D=%s 0x14=%s using=0x%02X\n",
+                gt_probe(0x5D) ? "OK" : "no", gt_probe(0x14) ? "OK" : "no",
+                s_gt_addr);
+  Serial.printf("GT911 SDA=%d SCL=%d INT=%d RST=%d\n", CYD_GT911_SDA,
+                CYD_GT911_SCL, CYD_GT911_INT, CYD_GT911_RST);
+}
+
+void touch_read_cb(lv_indev_t * /*indev*/, lv_indev_data_t *data) {
+  uint8_t info = 0;
+  static uint32_t last_log = 0;
+  const bool do_log = (millis() - last_log > 200);
+
+  if (!gt_read(GT_POINT_INFO, &info, 1)) {
+    data->state = LV_INDEV_STATE_RELEASED;
+    g_dbg_touch_down = false;
+    if (do_log) {
+      last_log = millis();
+      Serial.println("TouchProbe GT911 I2C err");
+    }
+    return;
+  }
+
+  const uint8_t touches = info & 0x0F;
+  const bool buffered = (info & 0x80) != 0;
+
+  if (!buffered || touches == 0) {
+    if (buffered) {
+      gt_write8(GT_POINT_INFO, 0);
+    }
+    data->state = LV_INDEV_STATE_RELEASED;
+    g_dbg_touch_down = false;
+    return;
+  }
+
+  uint8_t pt[7];
+  if (!gt_read(GT_POINT_1, pt, 7)) {
+    gt_write8(GT_POINT_INFO, 0);
+    data->state = LV_INDEV_STATE_RELEASED;
+    g_dbg_touch_down = false;
+    return;
+  }
+  gt_write8(GT_POINT_INFO, 0);
+
+  const int16_t raw_x = (int16_t)(pt[1] | (pt[2] << 8));
+  const int16_t raw_y = (int16_t)(pt[3] | (pt[4] << 8));
+
+  /* Native 320x480 → LVGL 270. Mirror long axis so L/R matches UI
+   * (else preset 3 hits 10). Resulting UI ≈ (H-1-raw_y, raw_x). */
+  const int16_t nx = clampi(raw_x, 0, SCREEN_WIDTH - 1);
+  const int16_t ny = clampi(raw_y, 0, SCREEN_HEIGHT - 1);
+  const int16_t feed_x = (int16_t)((SCREEN_WIDTH - 1) - nx);
+  const int16_t feed_y = (int16_t)((SCREEN_HEIGHT - 1) - ny);
+  const int16_t ui_x = (int16_t)((SCREEN_HEIGHT - 1) - ny);
+  const int16_t ui_y = nx;
+
+  g_dbg_phys_x = raw_x;
+  g_dbg_phys_y = raw_y;
+  g_dbg_logic_x = ui_x;
+  g_dbg_logic_y = ui_y;
+  g_dbg_touch_down = true;
+
+  if (do_log) {
+    last_log = millis();
+    Serial.printf("Touch HIT GT911 raw(%d,%d) ~ui(%d,%d)\n", raw_x, raw_y,
+                  ui_x, ui_y);
+  }
+
+  data->point.x = feed_x;
+  data->point.y = feed_y;
+  data->state = LV_INDEV_STATE_PRESSED;
+}
+
+#else
+
 static void soft_write(uint8_t data) {
  for (int i = 7; i >= 0; --i) {
    digitalWrite(CYD_TOUCH_MOSI, (data >> i) & 1);
@@ -49,16 +219,6 @@ static uint16_t xpt_read(uint8_t cmd) {
  return v;
 }

-static int16_t clampi(int32_t v, int32_t lo, int32_t hi) {
-  if (v < lo) {
-    return (int16_t)lo;
-  }
-  if (v > hi) {
-    return (int16_t)hi;
-  }
-  return (int16_t)v;
-}
-
 void touch_init() {
  pinMode(CYD_TOUCH_CS, OUTPUT);
  pinMode(CYD_TOUCH_CLK, OUTPUT);
@@ -94,8 +254,6 @@ void touch_read_cb(lv_indev_t * /*indev*/, lv_indev_data_t *data) {
  x = clampi(x, 0, SCREEN_WIDTH - 1);
  y = clampi(y, 0, SCREEN_HEIGHT - 1);

-  // 旧 UI（LVGL270）：(y, 239-x) — 该空间里 BL↔TR，做主对角线镜像
-  // (ux,uy) -> (uy*(319/239), ux*(239/319))
  const int32_t old_ux = y;
  const int32_t old_uy = (SCREEN_WIDTH - 1) - x;
  int16_t ui_x = clampi((old_uy * (UI_HOR_RES - 1)) / (UI_VER_RES - 1), 0,
@@ -103,7 +261,6 @@ void touch_read_cb(lv_indev_t * /*indev*/, lv_indev_data_t *data) {
  int16_t ui_y = clampi((old_ux * (UI_VER_RES - 1)) / (UI_HOR_RES - 1), 0,
                        UI_VER_RES - 1);

-  // 反变换喂 LVGL，使最终落在 (ui_x, ui_y)
  const int16_t feed_x = (int16_t)((SCREEN_WIDTH - 1) - ui_y);
  const int16_t feed_y = ui_x;

@@ -123,3 +280,5 @@ void touch_read_cb(lv_indev_t * /*indev*/, lv_indev_data_t *data) {
  data->point.y = feed_y;
  data->state = LV_INDEV_STATE_PRESSED;
 }
+
+#endif