初始提交卡包 USB 工程

纳入固件源码、屏幕组件、nand_xfer 工具和文档。忽略本机构建产物、sdkconfig，以及含本机路径的依赖锁。

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

main/NS4168/ns4168.h

@@ -0,0 +1,29 @@
+#ifndef __NS4168_H__
+#define __NS4168_H__
+
+#include "driver/gpio.h"
+#include "driver/i2s.h"
+#include "esp_err.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* 先用宏定义占位引脚，后续再改成实际板子上的 GPIO */
+#define NS4168_I2S_PORT          I2S_NUM_1
+#define NS4168_CTRL_GPIO         GPIO_NUM_33
+#define NS4168_I2S_BCK_PIN       GPIO_NUM_31
+#define NS4168_I2S_WS_PIN        GPIO_NUM_32
+#define NS4168_I2S_DOUT_PIN      GPIO_NUM_30
+#define NS4168_I2S_SAMPLE_RATE   24000
+#define NS4168_I2S_BITS          I2S_BITS_PER_SAMPLE_16BIT
+#define NS4168_I2S_CHANNELS      I2S_CHANNEL_FMT_ONLY_RIGHT
+
+esp_err_t ns4168_i2s_init(void);
+esp_err_t ns4168_start_white_noise_test(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __NS4168_H__ */