Dear FreeRTOS sirs,

I got a problem as below:
A task will be blocked when call the xQueyeSendToBack in queue is full, even the queue become to empty.

Info:
1. FreeRTOS v7.4.0
2. Queue length = 1 (unit)

Which CPU are you using?
Which FreeRTOS version are you using?
Do you have a basic FreeRTOS application running.
Does the queue ever work or do you always have this problem?
What is posting to the queue?
How is the queue created?

http://www.freertos.org/FAQ-how-to-use-the-FreeRTOS-support-forum.html

Regards.

Dear Sir,

1. CPU: LPC1768
2. FreeRTOS Version: v7.4.0
3. I have 3 tasks ruing , a Task in to blocked when query is full with xTicksToWait=portMAX_DELAY, even the queue become to empty by other task.
4. I post an integer data pointer to the queue (size=4), queue length = 1
5. queue create by xQueueCreate

Note:
If parameter xTicksToWait is 100, all task are work fine.

Have you ensured all the points listed on the following two pages have been followed? As you are using a Cortex-M the second page is important if you are sending to the queue from an ISR.

http://www.freertos.org/FAQHelp.html
http://www.freertos.org/RTOS-Cortex-M3-M4.html

If the information on those pages does not help then please post your queue create, send and receive code.

Regards.