定义循环缓存.doc

? 定义循环缓存： #define?? MAX_BUFF_LEN???? 1024??? // 定义缓存大小 typedef struct??? // 定义数据结构 { ??? uint??? data; }DATA_BUFF_T; typedef struct ???// 定义缓存结构 { ??? uint??? readPos; ??? uint??? writePos; ?? ?DATA_BUFF_T??? DATA[MAX_BUFF_LEN]; }DATAS_BUFF_T; static DATAS_BUFF_T?? Buff0; ???// 定义缓存 （2）初始化循环缓存： Buff0.readPos = 0; Buff0.writePos = 0; （3）判断缓存中是否有数据： BOOL HaveData_Buff(void) { ????if (Buff0.readPos != Buff0.write.Pos) ?????????? return 1; ???????else ?????????? return 0; ???} （4）向缓存中写数据： int?WriteData(uint data) { ??? uint??? nextPos; ??? nextPos = (Buff0.writePos + 1) % MAX_BUFF_LEN; ??? if (nectPos != Buff0.readPos)??? // 判断缓存是否满，需要写入数据的位置等于读数据的位置时 ??? { ??????? Buff0.DATA[writePos].data = data; ??????? Buff0.writePos = nextPos; ??????? return 0;??? //成功 ??? } ??? else ?????????? return -1; ?? } （5）从缓存中读数据： uint ReadData(void) { ??? uint dataTemp; ??? if (HaveData_Buff() == 0) ??? { ??????? printf(buffer is empty\n); ??????? return -1; ??? } ????dataTemp = Buff0.DATA[readPos].data; ????Buff0.readPos = (Buff0.readPos + 1) % MAX_BUFF_LEN; ????return dataTemp; }