feat: Initial esp32-hacking project with firmware sources and docs

esp-crab/slave_recv/main/app/app_uart.h

@@ -0,0 +1,26 @@
+
+#pragma once
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define UART_PORT_NUM      UART_NUM_0
+#define UART_BAUD_RATE     2000000
+#define TXD_PIN            (GPIO_NUM_11)
+#define RXD_PIN            (GPIO_NUM_12)
+#define BUF_SIZE           4096
+
+typedef struct {
+    uint8_t start[2];      
+    uint32_t id;           
+    int64_t time_delta;    
+    float cir[4];          
+    uint8_t end[2];        
+} __attribute__((packed)) csi_data_t;
+
+void init_uart(void);
+int uart_send_data(const char *data, uint8_t len);
+
+#ifdef __cplusplus
+}
+#endif