Add INMP441 sound-level meter for CYD 2.8/3.5.

I2S mic on WS22/SCK27(SD35) with LVGL dB gauge, peak/min-max and firmware pack. Co-authored-by: Cursor <cursoragent@cursor.com>
2026-10-27 20:49:12 +08:00
commit 59b85fb7dc
23 changed files with 1409 additions and 0 deletions
--- a/.cursor/rules/git-and-docs.mdc
+++ b/.cursor/rules/git-and-docs.mdc
@@ -0,0 +1,14 @@
+---
+description: 每次改动必须提交 Git 并更新文档
+alwaysApply: true
+---
+
+# Git 与文档
+
+对本项目做任何功能、行为或配置改动后，在结束本次任务前必须：
+
+1. **更新文档**：至少更新 `README.md` 的「功能 / 硬件 / 变更记录」中受影响部分；行为变更写进变更记录表。
+2. **提交 Git**：`git add` 相关文件后 `git commit`（按仓库既有 message 风格；中英文均可，说明 why）。
+3. **不要**在未提交的情况下声称任务已完成。
+
+例外：用户明确说「先别提交」或「不要改文档」时，以用户当次指令为准。
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1,8 @@
+.pio
+.vscode/.browse.c_cpp.db*
+.vscode/c_cpp_properties.json
+.vscode/launch.json
+.vscode/ipch
+*.pyc
+__pycache__/
+.DS_Store
--- a/README.md
+++ b/README.md
@@ -0,0 +1,86 @@
+# CYD INMP441 声贝检测
+
+ESP32 Cheap Yellow Display + INMP441（I2S）+ LVGL 声级仪表盘（近似 dB SPL）。
+
+默认 **2.8" ESP32-2432S028R**；可选 **3.5" ESP32-3248S035C**（`cyd_35r`）。  
+引脚约定见同目录 [CYD_PROJECT_GUIDE.md](../CYD_PROJECT_GUIDE.md)；UI 壳参考 [sgp30test](../sgp30test)。
+
+## 硬件
+
+| 项目 | 2.8" · 2432S028R | 3.5" C · 3248S035C |
+|------|------------------|---------------------|
+| 屏驱 | ILI9341 | ST7796 |
+| 触控 | XPT2046 SoftSPI | GT911 Wire1（SDA33/SCL32/INT21/RST25） |
+| 背光 TFT_BL | **GPIO21** | **GPIO27** |
+| INMP441 WS | **GPIO22**（CN1/P3） | **GPIO22** |
+| INMP441 SCK | **GPIO27**（CN1） | **GPIO21**（CN1；勿占 27=BL） |
+| INMP441 SD | **GPIO35**（P3，仅输入） | **GPIO35** |
+| 供电 | USB 5V；麦克风 **3.3V** | 同左 |
+
+接线：
+
+| INMP441 | CYD |
+|---------|-----|
+| VDD | 3.3V（CN1） |
+| GND | GND |
+| L/R | GND（左声道，勿悬空） |
+| WS | IO22 |
+| SCK | IO27（2.8）/ IO21（3.5） |
+| SD | IO35（P3） |
+
+> 不要接 5V；不要占用背光脚。I2S 需要三根信号线，仅 IO22+IO27 不够。
+
+## 功能
+
+- 大圆弧显示近似 **dB SPL**（基于 INMP441 −26 dBFS @ 94 dB 的换算，非标定声级计）
+- 分级：QUIET / SOFT / NORMAL / LOUD / VERY LOUD / DANGER
+- PEAK 峰值保持（缓慢回落）、MIN/MAX、电平条、底部趋势图
+- EMA 平滑；串口打印 `dB / rms / peak`
+- 短按切换背光（4 档）；长按 ≥0.7s 重置 min/max
+- 常亮运行（无自动熄屏）
+
+## 构建与烧录
+
+依赖 [PlatformIO](https://platformio.org/)。
+
+```bash
+pio run -e cyd_28r -t upload          # 2.8"
+pio run -e cyd_35r -t upload          # 3.5C
+pio device monitor -b 115200
+```
+
+### 预编译固件
+
+| 板型 | 目录 |
+|------|------|
+| 2.8" | [`firmware/cyd_28r/`](firmware/cyd_28r/) |
+| 3.5" | [`firmware/cyd_35r/`](firmware/cyd_35r/) |
+
+```powershell
+cd firmware\cyd_28r   # 或 cyd_35r
+.\flash.ps1
+```
+
+重新打包：
+
+```powershell
+.\firmware\export_from_build.ps1
+.\firmware\export_from_build.ps1 -Env cyd_35r
+```
+
+## 项目结构
+
+```
+platformio.ini
+include/pins.h lv_conf.h touch.h
+src/main.cpp touch.cpp
+scripts/exclude_lvgl_asm.py
+firmware/
+README.md
+```
+
+## 变更记录
+
+| 日期 | 说明 |
+|------|------|
+| 2026-10-27 | 初版：INMP441 I2S 声贝仪表盘（WS22/SCK27/SD35），LVGL 圆弧 + peak/min/max + 趋势图 |
--- a/firmware/README.md
+++ b/firmware/README.md
@@ -0,0 +1,24 @@
+# 预编译固件（可随时刷写）
+
+| 目录 | 板子 | INMP441 | 背光 |
+|------|------|---------|------|
+| [`cyd_28r/`](cyd_28r/) | ESP32-2432S028R（ILI9341） | WS=22 / SCK=27 / SD=35 | GPIO21 |
+| [`cyd_35r/`](cyd_35r/) | ESP32-3248S035C（ST7796 + GT911） | WS=22 / SCK=21 / SD=35 | GPIO27 |
+
+版本信息见各目录 `VERSION.txt`。引脚约定见 [`../CYD_PROJECT_GUIDE.md`](../../CYD_PROJECT_GUIDE.md)。
+
+## 直接刷写
+
+```powershell
+cd firmware\cyd_28r   # 或 cyd_35r
+.\flash.ps1
+# .\flash.ps1 -Port COM3
+```
+
+## 从源码重新打包
+
+```powershell
+.\firmware\export_from_build.ps1
+.\firmware\export_from_build.ps1 -Env cyd_35r
+.\firmware\export_from_build.ps1 -SkipBuild
+```
--- a/firmware/cyd_28r/VERSION.txt
+++ b/firmware/cyd_28r/VERSION.txt
@@ -0,0 +1,17 @@
+name: CYD inmp441test (cyd_28r)
+git: unknown
+date: 2026-10-27
+board: ESP32-2432S028R (ILI9341)
+inmp441: WS=GPIO22 SCK=GPIO27 SD=GPIO35
+tft_bl: GPIO21
+flash_size: 4MB
+offsets:
+  0x1000  bootloader.bin
+  0x8000  partitions.bin
+  0xe000  boot_app0.bin
+  0x10000 firmware.bin
+sha256:
+  bootloader.bin  3D234A7471F67B013686DABD4DEE7C1FA915C9928463616A94BC9297ACF1ABF8
+  boot_app0.bin   F94C5D786A7A8FAB06AC5D10E33BF37711A6697636DC037559EA19CC410A17F0
+  firmware.bin    0CA34A45377F5EDCAB501E510F97B28A9B7FCEB34D6C65F0B71691C784C41999
+  partitions.bin  0A8B5720E7B77FF11F1462458C3A509DEE79224E5279898F26D6A2E3AE0517B7
--- a/firmware/cyd_28r/boot_app0.bin
+++ b/firmware/cyd_28r/boot_app0.bin
--- a/firmware/cyd_28r/bootloader.bin
+++ b/firmware/cyd_28r/bootloader.bin
--- a/firmware/cyd_28r/firmware.bin
+++ b/firmware/cyd_28r/firmware.bin
--- a/firmware/cyd_28r/flash.bat
+++ b/firmware/cyd_28r/flash.bat
@@ -0,0 +1,5 @@
+@echo off
+setlocal
+cd /d "%~dp0"
+powershell -NoProfile -ExecutionPolicy Bypass -File "%~dp0flash.ps1" %*
+exit /b %ERRORLEVEL%
--- a/firmware/cyd_28r/flash.ps1
+++ b/firmware/cyd_28r/flash.ps1
@@ -0,0 +1,84 @@
+# Flash archived CYD INMP441 sound-meter firmware (no rebuild needed)
+# Usage:
+#   .\flash.ps1
+#   .\flash.ps1 -Port COM5
+#   .\flash.ps1 -Port COM5 -Baud 460800
+
+param(
+  [string]$Port = "",
+  [int]$Baud = 921600
+)
+
+$ErrorActionPreference = "Stop"
+$here = Split-Path -Parent $MyInvocation.MyCommand.Path
+Set-Location $here
+
+function Find-Esptool {
+  $pio = Get-Command pio -ErrorAction SilentlyContinue
+  if ($pio) {
+    $pkg = Join-Path $env:USERPROFILE ".platformio\packages\tool-esptoolpy\esptool.py"
+    if (Test-Path $pkg) { return @{ Kind = "py"; Path = $pkg } }
+  }
+  $py = Get-Command python -ErrorAction SilentlyContinue
+  if ($py) {
+    try {
+      & python -c "import esptool" 2>$null
+      if ($LASTEXITCODE -eq 0) { return @{ Kind = "mod"; Path = "esptool" } }
+    } catch {}
+  }
+  $esp = Get-Command esptool.py -ErrorAction SilentlyContinue
+  if ($esp) { return @{ Kind = "py"; Path = $esp.Source } }
+  return $null
+}
+
+if (-not $Port) {
+  $ports = @()
+  try {
+    Add-Type -AssemblyName System.IO.Ports -ErrorAction SilentlyContinue | Out-Null
+    $ports = [System.IO.Ports.SerialPort]::GetPortNames() | Sort-Object
+  } catch {}
+  if (-not $ports -or $ports.Count -eq 0) {
+    $ports = Get-CimInstance Win32_SerialPort -ErrorAction SilentlyContinue |
+      Select-Object -ExpandProperty DeviceID | Sort-Object
+  }
+  if (-not $ports -or $ports.Count -eq 0) {
+    Write-Error "No serial ports found. Plug in the CYD USB cable, then retry with -Port COMx"
+  }
+  if ($ports.Count -eq 1) {
+    $Port = $ports[0]
+  } else {
+    Write-Host "Available ports: $($ports -join ', ')"
+    $Port = $ports[-1]
+    Write-Host "Using last port: $Port (override with -Port)"
+  }
+}
+
+$tool = Find-Esptool
+if (-not $tool) {
+  Write-Error "esptool not found. Install PlatformIO (`pio`) or: pip install esptool"
+}
+
+$argsCommon = @(
+  "--chip", "esp32",
+  "--port", $Port,
+  "--baud", "$Baud",
+  "--before", "default_reset",
+  "--after", "hard_reset",
+  "write_flash", "-z",
+  "--flash_mode", "dio",
+  "--flash_freq", "40m",
+  "--flash_size", "4MB",
+  "0x1000", "bootloader.bin",
+  "0x8000", "partitions.bin",
+  "0xe000", "boot_app0.bin",
+  "0x10000", "firmware.bin"
+)
+
+Write-Host "Flashing $here -> $Port @ $Baud"
+if ($tool.Kind -eq "mod") {
+  & python -m esptool @argsCommon
+} else {
+  & python $tool.Path @argsCommon
+}
+if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+Write-Host "Done. Open serial monitor at 115200 if needed."
--- a/firmware/cyd_28r/meta.json
+++ b/firmware/cyd_28r/meta.json
@@ -0,0 +1,7 @@
+{
+  "boardId": "esp32-2432s028",
+  "name": "CYD INMP441 sound level meter",
+  "summary": "Approximate dB SPL gauge from INMP441",
+  "description": "INMP441 on WS=GPIO22 / SCK=GPIO27 / SD=GPIO35. Live dB arc, peak, min/max, trend chart.",
+  "tags": ["sound", "inmp441", "i2s", "db", "mic"]
+}
--- a/firmware/cyd_28r/partitions.bin
+++ b/firmware/cyd_28r/partitions.bin
--- a/firmware/cyd_35r/flash.bat
+++ b/firmware/cyd_35r/flash.bat
@@ -0,0 +1,5 @@
+@echo off
+setlocal
+cd /d "%~dp0"
+powershell -NoProfile -ExecutionPolicy Bypass -File "%~dp0flash.ps1" %*
+exit /b %ERRORLEVEL%
--- a/firmware/cyd_35r/flash.ps1
+++ b/firmware/cyd_35r/flash.ps1
@@ -0,0 +1,84 @@
+# Flash archived CYD SGP30 firmware (no rebuild needed)
+# Usage:
+#   .\flash.ps1
+#   .\flash.ps1 -Port COM5
+#   .\flash.ps1 -Port COM5 -Baud 460800
+
+param(
+  [string]$Port = "",
+  [int]$Baud = 921600
+)
+
+$ErrorActionPreference = "Stop"
+$here = Split-Path -Parent $MyInvocation.MyCommand.Path
+Set-Location $here
+
+function Find-Esptool {
+  $pio = Get-Command pio -ErrorAction SilentlyContinue
+  if ($pio) {
+    $pkg = Join-Path $env:USERPROFILE ".platformio\packages\tool-esptoolpy\esptool.py"
+    if (Test-Path $pkg) { return @{ Kind = "py"; Path = $pkg } }
+  }
+  $py = Get-Command python -ErrorAction SilentlyContinue
+  if ($py) {
+    try {
+      & python -c "import esptool" 2>$null
+      if ($LASTEXITCODE -eq 0) { return @{ Kind = "mod"; Path = "esptool" } }
+    } catch {}
+  }
+  $esp = Get-Command esptool.py -ErrorAction SilentlyContinue
+  if ($esp) { return @{ Kind = "py"; Path = $esp.Source } }
+  return $null
+}
+
+if (-not $Port) {
+  $ports = @()
+  try {
+    Add-Type -AssemblyName System.IO.Ports -ErrorAction SilentlyContinue | Out-Null
+    $ports = [System.IO.Ports.SerialPort]::GetPortNames() | Sort-Object
+  } catch {}
+  if (-not $ports -or $ports.Count -eq 0) {
+    $ports = Get-CimInstance Win32_SerialPort -ErrorAction SilentlyContinue |
+      Select-Object -ExpandProperty DeviceID | Sort-Object
+  }
+  if (-not $ports -or $ports.Count -eq 0) {
+    Write-Error "No serial ports found. Plug in the CYD USB cable, then retry with -Port COMx"
+  }
+  if ($ports.Count -eq 1) {
+    $Port = $ports[0]
+  } else {
+    Write-Host "Available ports: $($ports -join ', ')"
+    $Port = $ports[-1]
+    Write-Host "Using last port: $Port (override with -Port)"
+  }
+}
+
+$tool = Find-Esptool
+if (-not $tool) {
+  Write-Error "esptool not found. Install PlatformIO (`pio`) or: pip install esptool"
+}
+
+$argsCommon = @(
+  "--chip", "esp32",
+  "--port", $Port,
+  "--baud", "$Baud",
+  "--before", "default_reset",
+  "--after", "hard_reset",
+  "write_flash", "-z",
+  "--flash_mode", "dio",
+  "--flash_freq", "40m",
+  "--flash_size", "4MB",
+  "0x1000", "bootloader.bin",
+  "0x8000", "partitions.bin",
+  "0xe000", "boot_app0.bin",
+  "0x10000", "firmware.bin"
+)
+
+Write-Host "Flashing $here -> $Port @ $Baud"
+if ($tool.Kind -eq "mod") {
+  & python -m esptool @argsCommon
+} else {
+  & python $tool.Path @argsCommon
+}
+if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+Write-Host "Done. Open serial monitor at 115200 if needed."
--- a/firmware/cyd_35r/meta.json
+++ b/firmware/cyd_35r/meta.json
@@ -0,0 +1,7 @@
+{
+  "boardId": "esp32-3248s035",
+  "name": "CYD INMP441 sound level meter",
+  "summary": "Approximate dB SPL gauge from INMP441",
+  "description": "INMP441 on WS=GPIO22 / SCK=GPIO21 / SD=GPIO35. Live dB arc, peak, min/max, trend chart.",
+  "tags": ["sound", "inmp441", "i2s", "db", "mic"]
+}
--- a/firmware/export_from_build.ps1
+++ b/firmware/export_from_build.ps1
@@ -0,0 +1,73 @@
+# Export firmware bins from PlatformIO build.
+# Default: 2.8" (cyd_28r -> firmware/cyd_28r)
+# 3.5":    .\firmware\export_from_build.ps1 -Env cyd_35r
+
+param(
+  [switch]$SkipBuild,
+  [ValidateSet("cyd_28r", "cyd_35r")]
+  [string]$Env = "cyd_28r"
+)
+
+$ErrorActionPreference = "Stop"
+$root = Split-Path -Parent (Split-Path -Parent $MyInvocation.MyCommand.Path)
+Set-Location $root
+
+$env:Path = "C:\Users\dsx2016\AppData\Local\Programs\Python\Python312\Scripts;" + $env:Path
+
+if (-not $SkipBuild) {
+  pio run -e $Env
+  if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+}
+
+$src = Join-Path $root (".pio\build\" + $Env)
+if ($Env -eq "cyd_35r") {
+  $dstName = "cyd_35r"
+  $boardLine = "board: ESP32-3248S035 (ST7796 + GT911)"
+  $micLine = "inmp441: WS=GPIO22 SCK=GPIO21 SD=GPIO35"
+  $blLine = "tft_bl: GPIO27"
+} else {
+  $dstName = "cyd_28r"
+  $boardLine = "board: ESP32-2432S028R (ILI9341)"
+  $micLine = "inmp441: WS=GPIO22 SCK=GPIO27 SD=GPIO35"
+  $blLine = "tft_bl: GPIO21"
+}
+$dst = Join-Path $root ("firmware\" + $dstName)
+New-Item -ItemType Directory -Force -Path $dst | Out-Null
+
+foreach ($f in @("bootloader.bin", "partitions.bin", "firmware.bin")) {
+  $p = Join-Path $src $f
+  if (-not (Test-Path $p)) { Write-Error "Missing build artifact: $p — build with: pio run -e $Env" }
+  Copy-Item $p $dst -Force
+}
+
+$bootApp = Join-Path $env:USERPROFILE ".platformio\packages\framework-arduinoespressif32\tools\partitions\boot_app0.bin"
+if (-not (Test-Path $bootApp)) {
+  Write-Error "boot_app0.bin not found under PlatformIO packages"
+}
+Copy-Item $bootApp (Join-Path $dst "boot_app0.bin") -Force
+
+$git = ""
+try { $git = (git -C $root rev-parse --short HEAD).Trim() } catch { $git = "unknown" }
+$date = Get-Date -Format "yyyy-MM-dd"
+$hashes = Get-ChildItem (Join-Path $dst "*.bin") | Get-FileHash -Algorithm SHA256
+$lines = @(
+  "name: CYD inmp441test ($dstName)",
+  "git: $git",
+  "date: $date",
+  $boardLine,
+  $micLine,
+  $blLine,
+  "flash_size: 4MB",
+  "offsets:",
+  "  0x1000  bootloader.bin",
+  "  0x8000  partitions.bin",
+  "  0xe000  boot_app0.bin",
+  "  0x10000 firmware.bin",
+  "sha256:"
+)
+foreach ($h in $hashes) {
+  $lines += ("  {0,-15} {1}" -f (Split-Path $h.Path -Leaf), $h.Hash)
+}
+$lines | Set-Content -Encoding utf8 (Join-Path $dst "VERSION.txt")
+
+Write-Host "Exported -> $dst (env=$Env git=$git)"
--- a/include/lv_conf.h
+++ b/include/lv_conf.h
@@ -0,0 +1,86 @@
+#ifndef LV_CONF_H
+#define LV_CONF_H
+
+#include <stdint.h>
+
+#define LV_COLOR_DEPTH 16
+
+#define LV_MEM_SIZE (48 * 1024U)
+#define LV_DEF_REFR_PERIOD 16
+#define LV_DPI_DEF 130
+
+/* ESP32 无 Helium，关掉以免 .S 汇编被错误预处理 */
+#define LV_USE_DRAW_SW_ASM LV_DRAW_SW_ASM_NONE
+
+#define LV_USE_OS LV_OS_NONE
+#define LV_USE_STDLIB_MALLOC LV_STDLIB_BUILTIN
+#define LV_USE_STDLIB_STRING LV_STDLIB_BUILTIN
+#define LV_USE_STDLIB_SPRINTF LV_STDLIB_BUILTIN
+
+#define LV_USE_LOG 0
+#define LV_USE_ASSERT_NULL 1
+#define LV_USE_ASSERT_MALLOC 1
+
+#define LV_FONT_MONTSERRAT_12 1
+#define LV_FONT_MONTSERRAT_14 1
+#define LV_FONT_MONTSERRAT_16 1
+#define LV_FONT_MONTSERRAT_20 1
+#define LV_FONT_MONTSERRAT_24 1
+#define LV_FONT_MONTSERRAT_28 1
+#define LV_FONT_MONTSERRAT_32 1
+#define LV_FONT_MONTSERRAT_40 1
+#define LV_FONT_DEFAULT &lv_font_montserrat_14
+
+#define LV_USE_FLOAT 1
+#define LV_USE_MATRIX 0
+
+#define LV_USE_LABEL 1
+#define LV_LABEL_TEXT_SELECTION 0
+#define LV_LABEL_LONG_TXT_HINT 1
+
+#define LV_USE_ARC 1
+#define LV_USE_BAR 1
+#define LV_USE_BTN 1
+#define LV_USE_BUTTON 1
+#define LV_USE_IMG 1
+#define LV_USE_IMAGE 1
+#define LV_USE_LINE 1
+#define LV_USE_SLIDER 1
+#define LV_USE_SWITCH 1
+#define LV_USE_TEXTAREA 0
+#define LV_USE_CHECKBOX 0
+#define LV_USE_DROPDOWN 0
+#define LV_USE_ROLLER 0
+#define LV_USE_TABLE 0
+#define LV_USE_CALENDAR 0
+#define LV_USE_CHART 1
+#define LV_USE_KEYBOARD 0
+#define LV_USE_LIST 0
+#define LV_USE_MENU 0
+#define LV_USE_MSGBOX 0
+#define LV_USE_SPAN 0
+#define LV_USE_SPINBOX 0
+#define LV_USE_SPINNER 1
+#define LV_USE_TABVIEW 0
+#define LV_USE_TILEVIEW 0
+#define LV_USE_WIN 0
+#define LV_USE_LED 1
+#define LV_USE_SCALE 1
+
+#define LV_USE_THEME_DEFAULT 1
+#define LV_THEME_DEFAULT_DARK 1
+#define LV_THEME_DEFAULT_GROW 0
+#define LV_THEME_DEFAULT_TRANSITION_TIME 80
+
+#define LV_USE_FLEX 1
+#define LV_USE_GRID 1
+
+#define LV_USE_TFT_ESPI 1
+
+#define LV_USE_OBSERVER 0
+#define LV_USE_SYSMON 0
+#define LV_USE_PROFILER 0
+#define LV_USE_DEMO_WIDGETS 0
+#define LV_USE_DEMO_BENCHMARK 0
+
+#endif /* LV_CONF_H */
--- a/include/pins.h
+++ b/include/pins.h
@@ -0,0 +1,21 @@
+#pragma once
+
+/* CYD + INMP441 I2S pin truth source — see ../CYD_PROJECT_GUIDE.md */
+
+#if defined(CYD_BOARD_3248S035)
+  /* 3.5C ESP32-3248S035C: BL=27; free peripheral pair is 22+21 */
+  #define TFT_BL_PIN 27
+  #define I2S_WS_PIN 22
+  #define I2S_SCK_PIN 21
+  #define I2S_SD_PIN 35
+  #define SCREEN_WIDTH 480
+  #define SCREEN_HEIGHT 320
+#else
+  /* 2.8 ESP32-2432S028R: BL=21; free peripheral pair is 22+27; SD on P3 IO35 */
+  #define TFT_BL_PIN 21
+  #define I2S_WS_PIN 22
+  #define I2S_SCK_PIN 27
+  #define I2S_SD_PIN 35
+  #define SCREEN_WIDTH 320
+  #define SCREEN_HEIGHT 240
+#endif
--- a/include/touch.h
+++ b/include/touch.h
@@ -0,0 +1,6 @@
+#pragma once
+
+#include <lvgl.h>
+
+void touch_init();
+void touch_read_cb(lv_indev_t *indev, lv_indev_data_t *data);
--- a/platformio.ini
+++ b/platformio.ini
@@ -0,0 +1,90 @@
+; CYD LVGL INMP441 sound-level (dB) meter
+; 2.8: WS=22 SCK=27 SD=35 BL=21; 3.5C: WS=22 SCK=21 SD=35 BL=27
+; see ../CYD_PROJECT_GUIDE.md
+[platformio]
+default_envs = cyd_28r
+
+[env]
+platform = espressif32@6.9.0
+board = esp32dev
+framework = arduino
+monitor_speed = 115200
+upload_speed = 921600
+board_build.partitions = min_spiffs.csv
+lib_deps =
+  lvgl/lvgl@9.2.2
+  bodmer/TFT_eSPI@2.5.43
+  https://github.com/PaulStoffregen/XPT2046_Touchscreen.git
+extra_scripts = pre:scripts/exclude_lvgl_asm.py
+build_flags =
+  -D CORE_DEBUG_LEVEL=0
+  -D USER_SETUP_LOADED=1
+  -D USE_HSPI_PORT=1
+  -D ILI9341_2_DRIVER=1
+  -D TFT_WIDTH=240
+  -D TFT_HEIGHT=320
+  -D TFT_MISO=12
+  -D TFT_MOSI=13
+  -D TFT_SCLK=14
+  -D TFT_CS=15
+  -D TFT_DC=2
+  -D TFT_RST=-1
+  -D TFT_BL=21
+  -D TFT_BACKLIGHT_ON=HIGH
+  -D SPI_FREQUENCY=40000000
+  -D SPI_READ_FREQUENCY=20000000
+  -D LOAD_GLCD=1
+  -D LOAD_FONT2=0
+  -D LOAD_FONT4=0
+  -D LOAD_FONT6=0
+  -D LOAD_FONT7=0
+  -D LOAD_FONT8=0
+  -D LOAD_GFXFF=0
+  -D SMOOTH_FONT=0
+  -D TOUCH_CS=-1
+  -D LV_CONF_INCLUDE_SIMPLE=1
+  -I include
+
+; 标准 CYD 2.8" 电阻触控 (ILI9341)
+[env:cyd_28r]
+build_flags =
+  ${env.build_flags}
+
+; 颜色反相版本（若画面色偏/发白可改用此环境）
+[env:cyd_28r_inv]
+build_flags =
+  ${env.build_flags}
+  -D TFT_INVERSION_ON=1
+
+; USB-C 双口 / 7789 变体
+[env:cyd_28_st7789]
+build_flags =
+  ${env.build_flags}
+  -U ILI9341_2_DRIVER
+  -D ST7789_DRIVER=1
+  -D TFT_RGB_ORDER=TFT_BGR
+  -D TFT_INVERSION_ON=1
+
+; Optional 3.5" CYD ESP32-3248S035C (ST7796 + GT911 capacitive). Default remains cyd_28r.
+; Build: pio run -e cyd_35r
+; Keep TOUCH_CS=-1 — GPIO33 is GT911 SDA, not resistive touch CS.
+; TFT_BL=27 (not 21 — 21 is GT911 INT / I2S SCK). GT911 uses Wire1.
+[env:cyd_35r]
+lib_deps =
+  lvgl/lvgl@9.2.2
+  bodmer/TFT_eSPI@2.5.43
+build_flags =
+  ${env.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
+  -DSUPPORT_TRANSACTIONS
+  -DTFT_RGB_ORDER=TFT_BGR
+  -ULV_MEM_SIZE
+  -DLV_MEM_SIZE=32768
--- a/scripts/exclude_lvgl_asm.py
+++ b/scripts/exclude_lvgl_asm.py
@@ -0,0 +1,13 @@
+"""Exclude LVGL Helium/Neon .S files that break ESP32 (xtensa) builds."""
+import shutil
+from pathlib import Path
+
+Import("env")  # type: ignore  # noqa: F821
+
+LIBDEPS = Path(env["PROJECT_LIBDEPS_DIR"]) / env["PIOENV"] / "lvgl"  # type: ignore  # noqa: F821
+
+for sub in ("draw/sw/blend/helium", "draw/sw/blend/neon"):
+    target = LIBDEPS / "src" / sub
+    if target.exists():
+        shutil.rmtree(target, ignore_errors=True)
+        print(f"Removed LVGL ASM path: {target}")
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -0,0 +1,586 @@
+/**
+ * CYD LVGL INMP441 声贝（近似 dB SPL）仪表盘
+ * 2.8 (2432S028R): WS=22 SCK=27 SD=35, TFT_BL=21
+ * 3.5C (3248S035C): WS=22 SCK=21 SD=35, TFT_BL=27 — see ../CYD_PROJECT_GUIDE.md
+ *
+ * L/R -> GND（左声道）；VDD -> 3.3V（勿接 5V）
+ */
+
+#include <Arduino.h>
+#include <lvgl.h>
+#include <TFT_eSPI.h>
+#include <driver/i2s.h>
+#include <math.h>
+#include "pins.h"
+#include "touch.h"
+
+#define I2S_PORT I2S_NUM_0
+#define SAMPLE_RATE 16000
+#define SAMPLE_BITS 32
+#define DMA_BUF_COUNT 4
+#define DMA_BUF_LEN 256
+#define READ_SAMPLES 512
+#define MIC_READ_MS 80
+#define EMA_ALPHA 0.40f
+#define PEAK_DECAY_DB 1.2f
+#define HISTORY_LEN 48
+#define DB_ARC_MIN 30
+#define DB_ARC_MAX 110
+/* INMP441 ≈ -26 dBFS @ 94 dB SPL → SPL ≈ dBFS + 120 */
+#define MIC_DB_OFFSET 120.0f
+
+#if defined(CYD_BOARD_3248S035)
+#define DRAW_BUF_SIZE (SCREEN_WIDTH * SCREEN_HEIGHT / 20 * (LV_COLOR_DEPTH / 8))
+#else
+#define DRAW_BUF_SIZE (SCREEN_WIDTH * SCREEN_HEIGHT / 10 * (LV_COLOR_DEPTH / 8))
+#endif
+
+#if defined(CYD_BOARD_3248S035)
+#define UI_M 10
+#define UI_G 10
+#define UI_HDR_H 32
+#define UI_GAUGE_H 168
+#define UI_GAUGE_W 280
+#define UI_INFO_W 170
+#define UI_ARC 130
+#else
+#define UI_M 6
+#define UI_G 6
+#define UI_HDR_H 22
+#define UI_GAUGE_H 124
+#define UI_GAUGE_W 188
+#define UI_INFO_W 114
+#define UI_ARC 96
+#endif
+#define UI_BOT_Y (UI_HDR_H + UI_G + UI_GAUGE_H + UI_G)
+#define UI_BOT_H (SCREEN_HEIGHT - UI_BOT_Y - UI_M)
+#define UI_BOT_W (SCREEN_WIDTH - 2 * UI_M)
+
+static const lv_color_t COL_BG = lv_color_hex(0x0A1018);
+static const lv_color_t COL_PANEL = lv_color_hex(0x121C2A);
+static const lv_color_t COL_EDGE = lv_color_hex(0x1E2C40);
+static const lv_color_t COL_TEXT = lv_color_hex(0xF2F5FA);
+static const lv_color_t COL_MUTED = lv_color_hex(0x7E90A8);
+static const lv_color_t COL_ACCENT = lv_color_hex(0x3DBF8C);
+static const lv_color_t COL_OK = lv_color_hex(0x4CAF7A);
+static const lv_color_t COL_WARN = lv_color_hex(0xE6B84D);
+static const lv_color_t COL_LOUD = lv_color_hex(0xF0A04B);
+static const lv_color_t COL_BAD = lv_color_hex(0xE05A5A);
+static const lv_color_t COL_ARC_BG = lv_color_hex(0x243247);
+static const lv_color_t COL_CHART_BG = lv_color_hex(0x0E1622);
+
+static uint32_t draw_buf[DRAW_BUF_SIZE / 4];
+static int32_t i2s_samples[READ_SAMPLES];
+
+static lv_obj_t *arc_db;
+static lv_obj_t *lbl_db_val;
+static lv_obj_t *lbl_level;
+static lv_obj_t *lbl_peak;
+static lv_obj_t *lbl_range;
+static lv_obj_t *lbl_rms;
+static lv_obj_t *lbl_status;
+static lv_obj_t *lbl_uptime;
+static lv_obj_t *lbl_hint;
+static lv_obj_t *led_status;
+static lv_obj_t *bar_level;
+static lv_obj_t *chart;
+static lv_chart_series_t *ser_db;
+
+static float disp_db = NAN;
+static float peak_db = NAN;
+static float min_db = NAN;
+static float max_db = NAN;
+static float last_rms = 0.0f;
+static uint32_t last_mic_ms = 0;
+static uint32_t last_ok_ms = 0;
+static uint32_t boot_ms = 0;
+static bool mic_ok = false;
+static uint8_t bright_level = 2;
+static const uint8_t BRIGHT_PWM[4] = {40, 90, 160, 255};
+static uint32_t hint_until_ms = 0;
+
+static void set_backlight(uint8_t level) {
+  bright_level = level & 0x03;
+  ledcWrite(0, BRIGHT_PWM[bright_level]);
+}
+
+static float ema(float prev, float sample) {
+  if (isnan(prev)) return sample;
+  return prev + EMA_ALPHA * (sample - prev);
+}
+
+static lv_color_t db_color(float db) {
+  if (isnan(db)) return COL_MUTED;
+  if (db < 50.0f) return COL_OK;
+  if (db < 70.0f) return COL_ACCENT;
+  if (db < 85.0f) return COL_WARN;
+  if (db < 95.0f) return COL_LOUD;
+  return COL_BAD;
+}
+
+static const char *db_level_text(float db) {
+  if (isnan(db)) return "NO DATA";
+  if (db < 40.0f) return "QUIET";
+  if (db < 55.0f) return "SOFT";
+  if (db < 70.0f) return "NORMAL";
+  if (db < 85.0f) return "LOUD";
+  if (db < 95.0f) return "VERY LOUD";
+  return "DANGER";
+}
+
+static void show_hint(const char *text, uint32_t ms) {
+  lv_label_set_text(lbl_hint, text);
+  lv_obj_remove_flag(lbl_hint, LV_OBJ_FLAG_HIDDEN);
+  lv_obj_move_foreground(lbl_hint);
+  hint_until_ms = millis() + ms;
+}
+
+static void reset_minmax(void) {
+  if (!isnan(disp_db)) {
+    min_db = max_db = disp_db;
+  } else {
+    min_db = max_db = NAN;
+  }
+  peak_db = disp_db;
+  show_hint("min/max reset", 1200);
+}
+
+static void touchscreen_read(lv_indev_t *indev, lv_indev_data_t *data) {
+  static bool was_pressed = false;
+  static uint32_t press_ms = 0;
+
+  touch_read_cb(indev, data);
+
+  if (data->state == LV_INDEV_STATE_PRESSED) {
+    if (!was_pressed) {
+      was_pressed = true;
+      press_ms = millis();
+    }
+  } else if (was_pressed) {
+    was_pressed = false;
+    uint32_t held = millis() - press_ms;
+    if (held >= 700) {
+      reset_minmax();
+    } else if (held < 400) {
+      set_backlight((bright_level + 1) & 0x03);
+      char buf[20];
+      lv_snprintf(buf, sizeof(buf), "brightness %u/3", (unsigned)bright_level);
+      show_hint(buf, 900);
+    }
+  }
+}
+
+static void arc_anim_exec(void *obj, int32_t v) {
+  lv_arc_set_value((lv_obj_t *)obj, v);
+}
+
+static void anim_arc(lv_obj_t *arc, int32_t value) {
+  int32_t cur = lv_arc_get_value(arc);
+  if (cur == value) return;
+  lv_anim_t a;
+  lv_anim_init(&a);
+  lv_anim_set_var(&a, arc);
+  lv_anim_set_values(&a, cur, value);
+  lv_anim_set_duration(&a, 280);
+  lv_anim_set_exec_cb(&a, arc_anim_exec);
+  lv_anim_set_path_cb(&a, lv_anim_path_ease_out);
+  lv_anim_start(&a);
+}
+
+static void bar_anim_exec(void *obj, int32_t v) {
+  lv_bar_set_value((lv_obj_t *)obj, v, LV_ANIM_OFF);
+}
+
+static void anim_bar(lv_obj_t *bar, int32_t value) {
+  int32_t cur = lv_bar_get_value(bar);
+  if (cur == value) return;
+  lv_anim_t a;
+  lv_anim_init(&a);
+  lv_anim_set_var(&a, bar);
+  lv_anim_set_values(&a, cur, value);
+  lv_anim_set_duration(&a, 220);
+  lv_anim_set_exec_cb(&a, bar_anim_exec);
+  lv_anim_set_path_cb(&a, lv_anim_path_ease_out);
+  lv_anim_start(&a);
+}
+
+static lv_obj_t *make_panel(lv_obj_t *parent, int x, int y, int w, int h) {
+  lv_obj_t *p = lv_obj_create(parent);
+  lv_obj_set_pos(p, x, y);
+  lv_obj_set_size(p, w, h);
+  lv_obj_set_style_bg_color(p, COL_PANEL, 0);
+  lv_obj_set_style_bg_opa(p, LV_OPA_COVER, 0);
+  lv_obj_set_style_border_color(p, COL_EDGE, 0);
+  lv_obj_set_style_border_width(p, 1, 0);
+  lv_obj_set_style_radius(p, 12, 0);
+  lv_obj_set_style_pad_all(p, 6, 0);
+  lv_obj_clear_flag(p, LV_OBJ_FLAG_SCROLLABLE);
+  return p;
+}
+
+static bool mic_init(void) {
+  i2s_config_t cfg = {};
+  cfg.mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_RX);
+  cfg.sample_rate = SAMPLE_RATE;
+  cfg.bits_per_sample = I2S_BITS_PER_SAMPLE_32BIT;
+  cfg.channel_format = I2S_CHANNEL_FMT_ONLY_LEFT;
+  cfg.communication_format = I2S_COMM_FORMAT_STAND_I2S;
+  cfg.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1;
+  cfg.dma_buf_count = DMA_BUF_COUNT;
+  cfg.dma_buf_len = DMA_BUF_LEN;
+  cfg.use_apll = false;
+  cfg.tx_desc_auto_clear = false;
+  cfg.fixed_mclk = 0;
+
+  i2s_pin_config_t pins = {};
+  pins.bck_io_num = I2S_SCK_PIN;
+  pins.ws_io_num = I2S_WS_PIN;
+  pins.data_out_num = I2S_PIN_NO_CHANGE;
+  pins.data_in_num = I2S_SD_PIN;
+
+  if (i2s_driver_install(I2S_PORT, &cfg, 0, NULL) != ESP_OK) {
+    Serial.println("I2S driver install failed");
+    return false;
+  }
+  if (i2s_set_pin(I2S_PORT, &pins) != ESP_OK) {
+    Serial.println("I2S set_pin failed");
+    return false;
+  }
+  i2s_zero_dma_buffer(I2S_PORT);
+  return true;
+}
+
+static bool mic_read_db(float *out_db, float *out_rms) {
+  size_t bytes_read = 0;
+  esp_err_t err = i2s_read(I2S_PORT, (void *)i2s_samples, sizeof(i2s_samples),
+                           &bytes_read, pdMS_TO_TICKS(40));
+  if (err != ESP_OK || bytes_read < sizeof(int32_t) * 32) {
+    return false;
+  }
+
+  int n = (int)(bytes_read / sizeof(int32_t));
+  double sum_sq = 0.0;
+  int used = 0;
+  for (int i = 0; i < n; i++) {
+    /* INMP441: 24-bit left-justified in 32-bit word */
+    int32_t s = i2s_samples[i] >> 8;
+    sum_sq += (double)s * (double)s;
+    used++;
+  }
+  if (used < 16) return false;
+
+  double rms = sqrt(sum_sq / (double)used);
+  *out_rms = (float)rms;
+  if (rms < 1.0) rms = 1.0;
+  /* dBFS vs 24-bit full scale, then map to approximate SPL */
+  float dbfs = 20.0f * log10f((float)rms / 8388607.0f);
+  *out_db = dbfs + MIC_DB_OFFSET;
+  if (*out_db < 0.0f) *out_db = 0.0f;
+  if (*out_db > 140.0f) *out_db = 140.0f;
+  return true;
+}
+
+static void create_ui(void) {
+  lv_obj_t *scr = lv_screen_active();
+  lv_obj_set_style_bg_color(scr, COL_BG, 0);
+  lv_obj_set_style_bg_opa(scr, LV_OPA_COVER, 0);
+  lv_obj_clear_flag(scr, LV_OBJ_FLAG_SCROLLABLE);
+
+  lv_obj_t *title = lv_label_create(scr);
+  lv_label_set_text(title, "SOUND");
+  lv_obj_set_style_text_font(title, &lv_font_montserrat_14, 0);
+  lv_obj_set_style_text_color(title, COL_TEXT, 0);
+  lv_obj_set_pos(title, UI_M, 4);
+
+  lbl_uptime = lv_label_create(scr);
+  lv_label_set_text(lbl_uptime, "up 00:00");
+  lv_obj_set_style_text_font(lbl_uptime, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(lbl_uptime, COL_MUTED, 0);
+  lv_obj_align_to(lbl_uptime, title, LV_ALIGN_OUT_RIGHT_MID, 8, 1);
+
+  led_status = lv_led_create(scr);
+  lv_obj_set_size(led_status, 9, 9);
+  lv_obj_align(led_status, LV_ALIGN_TOP_RIGHT, -UI_M, 6);
+  lv_led_set_color(led_status, COL_WARN);
+  lv_led_on(led_status);
+
+  lbl_status = lv_label_create(scr);
+  lv_label_set_text(lbl_status, "INIT");
+  lv_obj_set_style_text_font(lbl_status, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(lbl_status, COL_MUTED, 0);
+  lv_obj_align(lbl_status, LV_ALIGN_TOP_RIGHT, -(UI_M + 16), 4);
+
+  lbl_hint = lv_label_create(scr);
+  lv_label_set_text(lbl_hint, "");
+  lv_obj_set_style_text_font(lbl_hint, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(lbl_hint, COL_WARN, 0);
+  lv_obj_set_style_bg_color(lbl_hint, COL_BG, 0);
+  lv_obj_set_style_bg_opa(lbl_hint, LV_OPA_COVER, 0);
+  lv_obj_set_style_pad_hor(lbl_hint, 6, 0);
+  lv_obj_align(lbl_hint, LV_ALIGN_TOP_MID, 0, 4);
+  lv_obj_add_flag(lbl_hint, LV_OBJ_FLAG_HIDDEN);
+
+  const int gy = UI_HDR_H + UI_G;
+
+  lv_obj_t *p_db = make_panel(scr, UI_M, gy, UI_GAUGE_W, UI_GAUGE_H);
+  lv_obj_t *cap = lv_label_create(p_db);
+  lv_label_set_text(cap, "dB SPL ~");
+  lv_obj_set_style_text_font(cap, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(cap, COL_MUTED, 0);
+  lv_obj_align(cap, LV_ALIGN_TOP_LEFT, 0, -2);
+
+  arc_db = lv_arc_create(p_db);
+  lv_obj_set_size(arc_db, UI_ARC, UI_ARC);
+  lv_obj_align(arc_db, LV_ALIGN_TOP_MID, 0, 2);
+  lv_arc_set_rotation(arc_db, 135);
+  lv_arc_set_bg_angles(arc_db, 0, 270);
+  lv_arc_set_range(arc_db, DB_ARC_MIN, DB_ARC_MAX);
+  lv_arc_set_value(arc_db, DB_ARC_MIN);
+  lv_obj_remove_style(arc_db, NULL, LV_PART_KNOB);
+  lv_obj_clear_flag(arc_db, LV_OBJ_FLAG_CLICKABLE);
+  lv_obj_set_style_arc_color(arc_db, COL_ARC_BG, LV_PART_MAIN);
+  lv_obj_set_style_arc_width(arc_db, 12, LV_PART_MAIN);
+  lv_obj_set_style_arc_color(arc_db, COL_ACCENT, LV_PART_INDICATOR);
+  lv_obj_set_style_arc_width(arc_db, 12, LV_PART_INDICATOR);
+  lv_obj_set_style_arc_rounded(arc_db, true, LV_PART_MAIN);
+  lv_obj_set_style_arc_rounded(arc_db, true, LV_PART_INDICATOR);
+
+  lbl_db_val = lv_label_create(p_db);
+  lv_label_set_text(lbl_db_val, "--.-");
+  lv_obj_set_style_text_font(lbl_db_val, &lv_font_montserrat_28, 0);
+  lv_obj_set_style_text_color(lbl_db_val, COL_ACCENT, 0);
+  lv_obj_align(lbl_db_val, LV_ALIGN_TOP_MID, 0, 30);
+
+  lv_obj_t *unit = lv_label_create(p_db);
+  lv_label_set_text(unit, "dB");
+  lv_obj_set_style_text_font(unit, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(unit, COL_MUTED, 0);
+  lv_obj_align(unit, LV_ALIGN_TOP_MID, 0, 62);
+
+  lbl_level = lv_label_create(p_db);
+  lv_label_set_text(lbl_level, "----");
+  lv_obj_set_style_text_font(lbl_level, &lv_font_montserrat_14, 0);
+  lv_obj_set_style_text_color(lbl_level, COL_MUTED, 0);
+  lv_obj_align(lbl_level, LV_ALIGN_BOTTOM_MID, 0, 2);
+
+  lv_obj_t *p_info = make_panel(scr, UI_M + UI_GAUGE_W + UI_G, gy, UI_INFO_W, UI_GAUGE_H);
+
+  lv_obj_t *p_cap = lv_label_create(p_info);
+  lv_label_set_text(p_cap, "PEAK");
+  lv_obj_set_style_text_font(p_cap, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(p_cap, COL_MUTED, 0);
+  lv_obj_align(p_cap, LV_ALIGN_TOP_LEFT, 0, -2);
+
+  lbl_peak = lv_label_create(p_info);
+  lv_label_set_text(lbl_peak, "--.-");
+  lv_obj_set_style_text_font(lbl_peak, &lv_font_montserrat_20, 0);
+  lv_obj_set_style_text_color(lbl_peak, COL_WARN, 0);
+  lv_obj_align(lbl_peak, LV_ALIGN_TOP_LEFT, 0, 14);
+
+  lv_obj_t *r_cap = lv_label_create(p_info);
+  lv_label_set_text(r_cap, "MIN / MAX");
+  lv_obj_set_style_text_font(r_cap, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(r_cap, COL_MUTED, 0);
+  lv_obj_align(r_cap, LV_ALIGN_TOP_LEFT, 0, 42);
+
+  lbl_range = lv_label_create(p_info);
+  lv_label_set_text(lbl_range, "-- / --");
+  lv_obj_set_style_text_font(lbl_range, &lv_font_montserrat_14, 0);
+  lv_obj_set_style_text_color(lbl_range, COL_TEXT, 0);
+  lv_obj_align(lbl_range, LV_ALIGN_TOP_LEFT, 0, 56);
+
+  bar_level = lv_bar_create(p_info);
+  lv_obj_set_size(bar_level, UI_INFO_W - 12, 12);
+  lv_obj_align(bar_level, LV_ALIGN_TOP_LEFT, 0, 82);
+  lv_bar_set_range(bar_level, DB_ARC_MIN, DB_ARC_MAX);
+  lv_bar_set_value(bar_level, DB_ARC_MIN, LV_ANIM_OFF);
+  lv_obj_set_style_bg_color(bar_level, COL_ARC_BG, LV_PART_MAIN);
+  lv_obj_set_style_bg_opa(bar_level, LV_OPA_COVER, LV_PART_MAIN);
+  lv_obj_set_style_radius(bar_level, 4, LV_PART_MAIN);
+  lv_obj_set_style_bg_color(bar_level, COL_ACCENT, LV_PART_INDICATOR);
+  lv_obj_set_style_radius(bar_level, 4, LV_PART_INDICATOR);
+
+  lbl_rms = lv_label_create(p_info);
+  lv_label_set_text(lbl_rms, "rms --");
+  lv_obj_set_style_text_font(lbl_rms, &lv_font_montserrat_12, 0);
+  lv_obj_set_style_text_color(lbl_rms, COL_MUTED, 0);
+  lv_obj_align(lbl_rms, LV_ALIGN_BOTTOM_LEFT, 0, 2);
+
+  lv_obj_t *p_bot = make_panel(scr, UI_M, UI_BOT_Y, UI_BOT_W, UI_BOT_H);
+  chart = lv_chart_create(p_bot);
+  lv_obj_set_size(chart, UI_BOT_W - 12, UI_BOT_H - 12);
+  lv_obj_align(chart, LV_ALIGN_CENTER, 0, 0);
+  lv_chart_set_type(chart, LV_CHART_TYPE_LINE);
+  lv_chart_set_point_count(chart, HISTORY_LEN);
+  lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_Y, DB_ARC_MIN, DB_ARC_MAX);
+  lv_chart_set_update_mode(chart, LV_CHART_UPDATE_MODE_SHIFT);
+  lv_obj_set_style_bg_color(chart, COL_CHART_BG, 0);
+  lv_obj_set_style_bg_opa(chart, LV_OPA_COVER, 0);
+  lv_obj_set_style_border_color(chart, COL_EDGE, 0);
+  lv_obj_set_style_border_width(chart, 1, 0);
+  lv_obj_set_style_radius(chart, 8, 0);
+  lv_obj_set_style_pad_all(chart, 4, 0);
+  lv_obj_set_style_line_width(chart, 2, LV_PART_ITEMS);
+  lv_chart_set_div_line_count(chart, 2, 4);
+  lv_obj_set_style_line_color(chart, COL_EDGE, LV_PART_MAIN);
+  lv_obj_set_style_line_opa(chart, LV_OPA_40, LV_PART_MAIN);
+  ser_db = lv_chart_add_series(chart, COL_ACCENT, LV_CHART_AXIS_PRIMARY_Y);
+
+  lv_obj_move_foreground(title);
+  lv_obj_move_foreground(lbl_uptime);
+  lv_obj_move_foreground(lbl_status);
+  lv_obj_move_foreground(led_status);
+  lv_obj_move_foreground(lbl_hint);
+}
+
+static void refresh_meta(void) {
+  char buf[40];
+  uint32_t up = millis() / 1000;
+  lv_snprintf(buf, sizeof(buf), "up %02lu:%02lu  bl%u",
+              (unsigned long)(up / 60), (unsigned long)(up % 60),
+              (unsigned)bright_level);
+  lv_label_set_text(lbl_uptime, buf);
+
+  if (hint_until_ms && (int32_t)(millis() - hint_until_ms) >= 0) {
+    hint_until_ms = 0;
+    lv_obj_add_flag(lbl_hint, LV_OBJ_FLAG_HIDDEN);
+  }
+
+  if (mic_ok) {
+    uint32_t age = (millis() - last_ok_ms) / 1000;
+    lv_snprintf(buf, sizeof(buf), "LIVE %lus", (unsigned long)age);
+    lv_label_set_text(lbl_status, buf);
+    lv_led_set_color(led_status, COL_OK);
+  } else {
+    lv_label_set_text(lbl_status, "NO MIC");
+    lv_led_set_color(led_status, COL_BAD);
+  }
+}
+
+static void update_ui(bool ok) {
+  char buf[32];
+
+  if (!ok || isnan(disp_db)) {
+    lv_label_set_text(lbl_db_val, "--.-");
+    lv_label_set_text(lbl_level, "NO DATA");
+    lv_obj_set_style_text_color(lbl_level, COL_BAD, 0);
+    lv_label_set_text(lbl_status, "ERR");
+    lv_led_set_color(led_status, COL_BAD);
+    return;
+  }
+
+  lv_color_t c = db_color(disp_db);
+  lv_snprintf(buf, sizeof(buf), "%.1f", disp_db);
+  lv_label_set_text(lbl_db_val, buf);
+  lv_obj_set_style_text_color(lbl_db_val, c, 0);
+  lv_obj_set_style_arc_color(arc_db, c, LV_PART_INDICATOR);
+  anim_arc(arc_db, (int)lroundf(constrain(disp_db, (float)DB_ARC_MIN, (float)DB_ARC_MAX)));
+
+  lv_label_set_text(lbl_level, db_level_text(disp_db));
+  lv_obj_set_style_text_color(lbl_level, c, 0);
+
+  lv_snprintf(buf, sizeof(buf), "%.1f", peak_db);
+  lv_label_set_text(lbl_peak, buf);
+  lv_obj_set_style_text_color(lbl_peak, db_color(peak_db), 0);
+
+  lv_snprintf(buf, sizeof(buf), "%.0f / %.0f", min_db, max_db);
+  lv_label_set_text(lbl_range, buf);
+
+  anim_bar(bar_level, (int)lroundf(constrain(disp_db, (float)DB_ARC_MIN, (float)DB_ARC_MAX)));
+  lv_obj_set_style_bg_color(bar_level, c, LV_PART_INDICATOR);
+
+  lv_snprintf(buf, sizeof(buf), "rms %.0f", last_rms);
+  lv_label_set_text(lbl_rms, buf);
+
+  lv_chart_set_next_value(chart, ser_db,
+                          (int32_t)lroundf(constrain(disp_db, (float)DB_ARC_MIN, (float)DB_ARC_MAX)));
+  lv_obj_set_style_line_color(chart, c, LV_PART_ITEMS);
+  refresh_meta();
+}
+
+static void read_mic(void) {
+  float db = NAN;
+  float rms = 0.0f;
+  if (!mic_read_db(&db, &rms)) {
+    mic_ok = false;
+    update_ui(false);
+    return;
+  }
+
+  mic_ok = true;
+  last_ok_ms = millis();
+  last_rms = rms;
+  disp_db = ema(disp_db, db);
+
+  if (isnan(peak_db) || db > peak_db) {
+    peak_db = db;
+  } else {
+    peak_db -= PEAK_DECAY_DB * (MIC_READ_MS / 1000.0f) * 10.0f;
+    if (peak_db < disp_db) peak_db = disp_db;
+  }
+
+  if (isnan(min_db) || disp_db < min_db) min_db = disp_db;
+  if (isnan(max_db) || disp_db > max_db) max_db = disp_db;
+
+  Serial.printf("dB=%.1f (raw %.1f) rms=%.0f peak=%.1f\n", disp_db, db, rms, peak_db);
+  update_ui(true);
+}
+
+void setup() {
+  Serial.begin(115200);
+  delay(200);
+  boot_ms = millis();
+
+  ledcSetup(0, 5000, 8);
+  ledcAttachPin(TFT_BL_PIN, 0);
+  set_backlight(2);
+
+  Serial.println("CYD LVGL INMP441 Sound Level Meter");
+  Serial.printf("LVGL %d.%d.%d  WS=%d SCK=%d SD=%d  BL=%d\n",
+                lv_version_major(), lv_version_minor(), lv_version_patch(),
+                I2S_WS_PIN, I2S_SCK_PIN, I2S_SD_PIN, TFT_BL_PIN);
+
+  touch_init();
+
+  bool ok = mic_init();
+  Serial.println(ok ? "I2S mic OK" : "I2S mic FAIL — check wiring");
+
+  lv_init();
+
+#if defined(CYD_BOARD_3248S035)
+  lv_display_t *disp = lv_tft_espi_create(320, 480, draw_buf, sizeof(draw_buf));
+#else
+  lv_display_t *disp = lv_tft_espi_create(240, 320, draw_buf, sizeof(draw_buf));
+#endif
+  lv_display_set_rotation(disp, LV_DISPLAY_ROTATION_270);
+
+  lv_indev_t *indev = lv_indev_create();
+  lv_indev_set_type(indev, LV_INDEV_TYPE_POINTER);
+  lv_indev_set_read_cb(indev, touchscreen_read);
+  lv_indev_set_display(indev, disp);
+
+  create_ui();
+  if (!ok) {
+    show_hint("mic init fail", 3000);
+  }
+  delay(100);
+  last_mic_ms = 0;
+}
+
+void loop() {
+  uint32_t now = millis();
+  if (now - last_mic_ms >= MIC_READ_MS) {
+    last_mic_ms = now;
+    read_mic();
+  }
+
+  static uint32_t last_meta_ms = 0;
+  if (now - last_meta_ms >= 1000) {
+    last_meta_ms = now;
+    refresh_meta();
+  }
+
+  lv_timer_handler();
+  lv_tick_inc(5);
+  delay(5);
+}
--- a/src/touch.cpp
+++ b/src/touch.cpp
@@ -0,0 +1,193 @@
+#include "touch.h"
+
+#include <Arduino.h>
+
+/**
+ * 2.8": XPT2046 resistive SoftSPI bus (CS33).
+ * 3.5C (3248S035C): GT911 capacitive on Wire1 SDA33/SCL32/INT21/RST25.
+ * Feed coords are always native panel 320x480 for LVGL ROTATION_270.
+ * Wire1 leaves Wire free for SGP30 (3.5: SDA22/SCL21; TFT_BL=27).
+ */
+
+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)
+
+#include <Wire.h>
+
+/* Native panel size — not UI landscape SCREEN_* (480x320). */
+static constexpr int16_t PANEL_W = 320;
+static constexpr int16_t PANEL_H = 480;
+
+#define CYD_GT911_SDA 33
+#define CYD_GT911_SCL 32
+#define CYD_GT911_INT 21
+#define CYD_GT911_RST 25
+
+/* 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) {
+  Wire1.beginTransmission(s_gt_addr);
+  Wire1.write((uint8_t)(reg >> 8));
+  Wire1.write((uint8_t)(reg & 0xFF));
+  Wire1.write(val);
+  return Wire1.endTransmission() == 0;
+}
+
+static bool gt_read(uint16_t reg, uint8_t *buf, uint8_t len) {
+  Wire1.beginTransmission(s_gt_addr);
+  Wire1.write((uint8_t)(reg >> 8));
+  Wire1.write((uint8_t)(reg & 0xFF));
+  if (Wire1.endTransmission(false) != 0) {
+    return false;
+  }
+  const uint8_t n = Wire1.requestFrom(s_gt_addr, len);
+  if (n != len) {
+    return false;
+  }
+  for (uint8_t i = 0; i < len; i++) {
+    buf[i] = Wire1.read();
+  }
+  return true;
+}
+
+static bool gt_probe(uint8_t addr) {
+  Wire1.beginTransmission(addr);
+  return Wire1.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 — release INT(21) as input (may share SCL for SGP30). */
+  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 Wire1");
+  Wire1.begin(CYD_GT911_SDA, CYD_GT911_SCL);
+  Wire1.setClock(100000);
+#if defined(WIRE_HAS_TIMEOUT) || defined(ESP32)
+  Wire1.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;
+
+  if (!gt_read(GT_POINT_INFO, &info, 1)) {
+    data->state = LV_INDEV_STATE_RELEASED;
+    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;
+    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;
+    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. UI ≈ (H-1-raw_y, raw_x). */
+  const int16_t nx = clampi(raw_x, 0, PANEL_W - 1);
+  const int16_t ny = clampi(raw_y, 0, PANEL_H - 1);
+  data->point.x = (int16_t)((PANEL_W - 1) - nx);
+  data->point.y = (int16_t)((PANEL_H - 1) - ny);
+  data->state = LV_INDEV_STATE_PRESSED;
+}
+
+#else
+
+#include <SPI.h>
+#include <XPT2046_Touchscreen.h>
+
+#define XPT2046_IRQ 36
+#define XPT2046_MOSI 32
+#define XPT2046_MISO 39
+#define XPT2046_CLK 25
+#define XPT2046_CS 33
+
+/* 2.8 UI landscape feed (unchanged from prior main.cpp). */
+static constexpr int16_t UI_W = 320;
+static constexpr int16_t UI_H = 240;
+
+static SPIClass touchscreenSPI = SPIClass(VSPI);
+static XPT2046_Touchscreen touchscreen(XPT2046_CS, XPT2046_IRQ);
+
+void touch_init() {
+  touchscreenSPI.begin(XPT2046_CLK, XPT2046_MISO, XPT2046_MOSI, XPT2046_CS);
+  touchscreen.begin(touchscreenSPI);
+  touchscreen.setRotation(2);
+  Serial.println("Touch: XPT2046 resistive (2.8)");
+}
+
+void touch_read_cb(lv_indev_t * /*indev*/, lv_indev_data_t *data) {
+  if (touchscreen.tirqTouched() && touchscreen.touched()) {
+    TS_Point p = touchscreen.getPoint();
+    data->point.x = map(p.y, 240, 3800, 1, UI_W);
+    data->point.y = map(p.x, 200, 3700, UI_H, 1);
+    data->state = LV_INDEV_STATE_PRESSED;
+  } else {
+    data->state = LV_INDEV_STATE_RELEASED;
+  }
+}
+
+#endif