Add CYD host PC info panel with serial SI protocol and LVGL bars.

ESP32 shows CPU/GPU/RAM/disk from host/send_sysinfo.ps1 over USB; firmware packages for 2.8 and 3.5 included.

Co-authored-by: Cursor <cursoragent@cursor.com>

include/host_info.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <stdint.h>
+
+/** Max chars for hostname / CPU / GPU name shown on UI. */
+static constexpr int HOST_NAME_MAX = 40;
+static constexpr int HOST_CPU_MAX = 48;
+static constexpr int HOST_GPU_MAX = 48;
+
+struct HostInfo {
+  char host[HOST_NAME_MAX];
+  char cpu[HOST_CPU_MAX];
+  char gpu[HOST_GPU_MAX];
+  float cpu_pct;      // 0..100
+  float gpu_pct;      // 0..100, -1 if unknown
+  float ram_used_gb;
+  float ram_total_gb;
+  float disk_used_gb;
+  float disk_total_gb;
+  bool valid;
+  uint32_t updated_ms;
+};
+
+void host_info_begin();
+/** Poll USB Serial for SI|... lines; return true if a packet was applied. */
+bool host_info_poll();
+const HostInfo &host_info_get();
+/** True if last packet is fresher than stale_ms. */
+bool host_info_is_live(uint32_t stale_ms = 5000);

include/pins.h

@@ -0,0 +1,42 @@
+#pragma once
+
+// Board pins — 2.8" default; 3.5" when CYD_BOARD_3248S035 is set (env:cyd_35r)
+
+#if defined(CYD_BOARD_3248S035)
+#define TFT_BL_PIN 27
+#define SCREEN_WIDTH  320
+#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
+/* 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))
+#define UY(y) ((int)(((long)(y) * (UI_VER_RES)) / 240))
+#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

include/touch.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <lvgl.h>
+#include <stdint.h>
+
+void touch_init();
+void touch_read_cb(lv_indev_t *indev, lv_indev_data_t *data);

include/ui.h

@@ -0,0 +1,4 @@
+#pragma once
+
+void ui_create();
+void ui_tick();