jxcrgt35 发表于 2018-8-11 16:15
如果数组是定长的，那更简单了for(i=0;i

这是那个结构体，提到的那个字符串数组就是这个payload
struct pbuf {
  /** next pbuf in singly linked pbuf chain */
  struct pbuf *next;

  /** pointer to the actual data in the buffer */
  void *payload;//指向缓存数组

  /**
   * total length of this buffer and all next buffers in chain
   * belonging to the same packet.
   *
   * For non-queue packet chains this is the invariant:
   * p->tot_len == p->len + (p->next? p->next->tot_len: 0)
   */
  u16_t tot_len;//数据包总的长度（数据包分到了几个buffer中）

  /** length of this buffer */
  u16_t len;//单个buffer的长度

  /** pbuf_type as u8_t instead of enum to save space */
  u8_t /*pbuf_type*/ type;//数据包类型

  /** misc flags */
  u8_t flags;

  /**
   * the reference count always equals the number of pointers
   * that refer to this pbuf. This can be pointers from an application,
   * the stack itself, or pbuf->next pointers from a chain.
   */
  u16_t ref;//引用pbuf的次数
};

本帖最后由 jxcrgt35 于 2018-8-12 23:37 编辑

unsigned char buf [100];

自己编写一个HexToChar函数，将U8数组16进制转换成字符（网上一大把）往缓冲区tcp_client_sendbuf[i++]填充，记得在结尾添加0x00,不知道这样能不能帮到你。