diff --git a/host_tasks.c b/host_tasks.c
index 3b4bd5c..8dc60a3 100644
--- a/host_tasks.c
+++ b/host_tasks.c
@@ -174,8 +174,22 @@ static void on_ins_connect(ins_connect_t *p_ins)
 
 static void on_ins_write_char(ins_write_char_t *p_ins)
 {
-    NRF_LOG_INFO("write handle: 0x%02X", p_ins->handle);
     uint16_t write_size = p_ins->len - sizeof(p_ins->handle) - 1;
+    NRF_LOG_INFO("write handle: 0x%02X", p_ins->handle);
+    {
+        uint8_t *p_start = (void *)p_ins->write_data;
+        uint32_t loop    = write_size / 8;
+        uint32_t remain  = write_size % 8;
+        for (int i = 0; i < loop; i++)
+        {
+            NRF_LOG_HEXDUMP_INFO(p_start, 8);
+            p_start += 8;
+        }
+        if (remain)
+        {
+            NRF_LOG_HEXDUMP_INFO(p_start, remain);
+        }
+    }
 
     extern ret_code_t le_gatt_c_write_req(uint32_t handle, void *, uint16_t);
     ret_code_t err_code = le_gatt_c_write_req(p_ins->handle, p_ins->write_data, write_size);
@@ -202,22 +216,38 @@ static void on_ins_survive(ins_survive_t *p_ins)
     success_ack();
 }
 
-typedef struct
-{
-    uint16_t rsp_code;
-    union
-    {
-        uint8_t len;
-        uint8_t payload[256];
-    };
-} __PACKED read_char_rsp_t;
-
-read_char_rsp_t read_char_rsp;
 void host_read_char_cb(uint8_t *p_data, uint16_t len)
 {
-    read_char_rsp.rsp_code = 0x0004;
-    memcpy(&read_char_rsp.len, p_data, len);
-    uart_drv_tx(&read_char_rsp, offsetof(read_char_rsp_t, payload) + len);
+    static union
+    {
+        struct
+        {
+            uint16_t rsp_code;
+            uint8_t payload[];
+        };
+        uint8_t arr[256];
+    } read_char_rsp = {
+        .rsp_code = 0x0004
+    };
+
+    memcpy(read_char_rsp.payload, p_data, len);
+
+    uart_drv_tx(&read_char_rsp, sizeof(read_char_rsp.rsp_code) + len);
+
+    {
+        uint8_t *p_start = p_data;
+        uint32_t loop    = len / 8;
+        uint32_t remain  = len % 8;
+        for (int i = 0; i < loop; i++)
+        {
+            NRF_LOG_HEXDUMP_INFO(p_start, 8);
+            p_start += 8;
+        }
+        if (remain)
+        {
+            NRF_LOG_HEXDUMP_INFO(p_start, remain);
+        }
+    }
 }
 
 typedef struct