本文展示了两种实现通信协议的方案：协程版本和基于OS的版本。 分别采用不同方式实现任务之间异步和同步操作实例
1、使用协程进行实现：
PT_THREAD(AxProtocolWaitPacket(tProtocolCommon *xUc, uint32_t xDataLen))
{
PT_BEGIN(&xUc->mPtSendRecvPacket);
AxProtocolUartReadReset(xUc);
xUc->mRetryCount = xUc->mRetryTotal;
do
{
xUc->mDly = get_time_now();
PT_WAIT_UNTIL(&xUc->mPtSendRecvPacket,
(AxProtocolUartReadCount(xUc) >= xDataLen)
|| (get_time_diff(get_time_now(), xUc->mDly) > xUc->mTimeout));
if(AxProtocolUartReadCount(xUc) >= xDataLen)
{
break;
}
}while(--xUc->mRetryCount);
if(xUc->mRetryCount == 0)
{
PT_EXIT(&xUc->mPtSendRecvPacket);
}
PT_END(&xUc->mPtSendRecvPacket);
}
//完成一包数据发送/接收的线程
PT_THREAD(AxProtocolSendRecvPacket(tProtocolCommon *xUc, const uint8_t *xData, uint32_t xDataLen,
uint8_t *xAck, uint32_t xAckLen))
{
PT_BEGIN(&xUc->mPtSendRecvPacket);
AxProtocolUartReadReset(xUc);
xUc->mRetryCount = xUc->mRetryTotal;
do
{
AxProtocolUartWrite(xUc, xData, xDataLen);
xUc->mDly = get_time_now();
PT_WAIT_UNTIL(&xUc->mPtSendRecvPacket,
(AxProtocolUartReadCount(xUc) >= xAckLen)
|| (get_time_diff(get_time_now(), xUc->mDly) > xUc->mTimeout));
if(AxProtocolUartReadCount(xUc) >= xAckLen)
{
break;
}
}while(--xUc->mRetryCount);
if(xUc->mRetryCount == 0)
{
PT_EXIT(&xUc->mPtSendRecvPacket);
}
AxProtocolUartRead(xUc, xAck, xAckLen);
PT_END(&xUc->mPtSendRecvPacket);
}
PT_THREAD(AxProtocolReadToDatas(tProtocolCommon *xUc, const uint8_t *xData, uint32_t xDataLen))
{
uint16_t cCnt;
uint8_t cFound = 0;
uint8_t cReadBuf[128];
if(xDataLen < sizeof(cReadBuf))
{
while(cCnt = AxProtocolUartReadCount(xUc), cCnt >= xDataLen)
{
AxProtocolUartPeek(xUc, cReadBuf, xDataLen);
if(memcmp(xData, cReadBuf, xDataLen) == 0)