_lwmsgq_receive（）函数使用 求指导

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result = _lwmsgq_receive((pointer)server_queue_a, msg_client_a, LWMSGQ_RECEIVE_BLOCK_ON_EMPTY,0,0);
来接收server_queue_a中的数据到msg_client_a中，如果server_queue_a中没有数据时，进程就会block在此处，如果想如果在1000ms内没有接到数据，程序不block在这里，应该怎么写

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还请大神帮忙指点一下

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急急急~~~

FSL_FAE_YDW

查手册可知，最后两个参数是和超时有关的设置

2.1.101 _lwmsgq_receive
Get a message from a lightweight message queue.
Synopsis
source\kernel\lwmsgq.c
#include <lwmsgq.h>
#include <lwmsgq_prv.h>
_mqx_uint _lwmsgq_receive(
  void                *handle,
  _mqx_max_type_ptr   message,
  _mqx_uint           flags,
  _mqx_uint           ticks,
  MQX_TICK_STRUCT_PTR tick_ptr)
Parameters
handle [IN] — Pointer to the message queue created by _lwmsgq_init
message [OUT] — Received message
flags [IN] — LWMSGQ_RECEIVE_BLOCK_ON_EMPTY(block the reading task if msgq is
empty), LWMSGQ_TIMEOUT_UNTIL (perform a timeout using the tick structure as the absolute
time), LWMSGQ_TIMEOUT_FOR (perform a timeout using the tick structure as the relative
time)
ticks [IN] — The maximum number of ticks to wait. If set to zero waiting time is controlled by the
tick_ptr input parameter value. When just LWMSGQ_RECEIVE_BLOCK_ON_EMPTY flags is
set and ticks input parameters is set to zero the receive function waits for an unlimited amount of
time.
tick_ptr [IN] — Pointer to the tick structure to use when ticks input parameter is set to zero.
Returns
• MQX_OK
• See error codes

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FSL_FAE_YDW 发表于 2015-8-19 08:50
查手册可知，最后两个参数是和超时有关的设置

2.1.101 _lwmsgq_receive

        MQX_TICK_STRUCT ticks;
        _time_init_ticks(&ticks, 100000);

result = _lwmsgq_receive((pointer)server_queue_a, msg_client_a, LWMSGQ_RECEIVE_BLOCK_ON_EMPTY,0,&ticks);

没有收到但是没有等10s立马就回复了

FSL_FAE_YDW

2.1.303 _time_get_ticks_per_sec,  _time_set_ticks_per_sec
Prototype
source\kernel\time.c
_mqx_uint _time_get_ticks_per_sec(void)
void  _time_set_ticks_per_sec(
  _mqx_uint ticks_per_sec)
Parameters
ticks_per_ sec [IN] — New timer frequency in ticks per second
Returns
• _time_get_ticks_per_sec():
Period of clock interrupt in ticks per second
你需要查一下目前这个系统里面每个tick多少时间，
可以通过下面的函数先获取每秒的tick数目

• _time_set_ticks_per_sec():
None
_time_get_ticks_per_sec() Gets the timer frequency (in ticks per second) that
MQX RTOS uses.
_time_set_ticks_per_sec() Sets the timer frequency (in ticks per second) that
MQX RTOS uses.

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FSL_FAE_YDW 发表于 2015-8-19 09:32
2.1.303 _time_get_ticks_per_sec,  _time_set_ticks_per_sec
Prototype
source\kernel\time.c

Hi，
_time_get_ticks_per_sec()返回的是200
需要用_time_set_ticks_per_sec()重新设置还是怎么滴呀

FSL_FAE_YDW

根据200来设置，200ticks是一秒

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FSL_FAE_YDW 发表于 2015-8-19 11:19
根据200来设置，200ticks是一秒

想设置超时1s的话是不是要这样
_lwmsgq_receive((pointer)server_queue_a, msg_client_a, LWMSGQ_RECEIVE_BLOCK_ON_EMPTY | LWMSGQ_TIMEOUT_UNTIL, 200, 0)
我试了下这样调用
_lwmsgq_receive((pointer)server_queue_a, msg_client_a, LWMSGQ_TIMEOUT_UNTIL, 200, 0)
这样调用不行

FSL_FAE_YDW

是指无法返回吗？还是收不到消息？