It takes me several days for debbuging ,but didn't work.
when the para 'timeout' of osMessagePut(id,info,timeout) is not set to 0, then the program crashes with info 'OS_ERROR_MBX_OVF' , which means mailbox overflow. But with timeout setting to 0,everything seems ok.
It really confuses me. Can anyone help me ? Thanks a lot!
The main frame of my program is as follows (it is from mdk example 'CAN_Ex', basically not changed much )
osPoolDef(rlcan_mpool, 80, CAN_msg); osMessageQDef(rlcan_msgq_tx, 20, CAN_msg); /* Thread1, used to send can message */ while(1) { ... /* check if hardware is free for send */ if (CAN_hw_tx_empty (ctrl) == CAN_OK) { CAN_hw_wr (ctrl, msg); /* Send message */ } else { ptrmsg = osPoolAlloc(rlcan_mpool); /* for timeout is not 0, it crashes after ISR getting about 16 messages */ result = osMessagePut(rlcan_msgq_tx, ptrmsg, 10); if (result != osOK) osPoolFree(rlcan_mpool, ptrmsg); } osDelay (500); } /* ISR, interrupt generates after msg sending succeeds */ void CAN0_ORed_Message_buffer_IRQHandler (void) { ... iflag1 = CANc->IFLAG1; //iflag1 will be set if msg sending succeeds while(iflag1) { iflag1 = 0; /* it crashes after getting about 16 messages */ evt = osMessageGet(rlcan_msgq_tx[CTRL0], 0); if (evt.status == osEventMessage) { CAN_hw_wr (CTRL,evt.value.p); /* Send message */ osPoolFree(rlcan_mpool, evt.value.p); } iflag1 = CANc->IFLAG1; //check whether iflag1 is set again } }
The "timeout" arguments specified in the "RTX_CAN.h" and "RTX_CAN.c" for a few functions such as CAN_ERROR CAN_send(); CAN_ERROR CAN_request(); CAN_ERROR CAN_set(); CAN_ERROR CAN_receive() have a wrong data type "uint16_t". They should be "uint32_t". This might be the reason for this issue. Please download the attached example project again via the following link: http://www.keil.com/support/docs/3714.htm This attached example project has just been updated to fix this bug on the 5th of Jun. 15.
Please let me know if this helps. Thx!
Sorry , but it still crashes .
Other info, the MCU is MK64F, and the pc software is Kvaser CanKing.
Perhaps the mailbox is really full.
How often has been a mail retrieved from the mailbox? You can evaluate that by using a counter.
Check also the parameters of the osMail functions. You should always pass the same queue_id to the functions. This seems not the case in your code example that you have provided.
See: www.keil.com/.../group___c_m_s_i_s___r_t_o_s___mail.html
thanks,Reinhard. But I use Message Queue, not mailbox.
Besides, If the queue is still full when time expires, the memory pool will be freed as the following code. And there's just one thread calling the 'osMessagePut' api, and whatever the value of timeout is set (except for '0'),it crashes.
/* for timeout is not 0, it crashes */ result = osMessagePut(rlcan_msgq_tx, ptrmsg, 10); if (result != osOK) { osPoolFree(rlcan_mpool, ptrmsg); }
The only time you can get the error you are describing is when the Post Service Handler Queue gets full. This queue is 16 deep by default. You may change this size, but my guess is the "Real" problem is not the queue depth but some other logic issue. The Post Service Handler Queue fills when you make Mailbox (either osMessage or osMailbox), Semaphore or event calls from an ISR. As long as you stay in an interrupt service routine, this queue will not be emptied. At the point that no more interrupts are pending, this queue is processed.
Sorry, I referred to mail instead of message functions.
Ensure that both functions: osMessageGet and osMessagePut get the same queue_id.
Once this is verified I suggest you trace the calls to both functions (i.e. increment two counters in your application and use the ULINKpro / MDK Logic Analyzer to see how the values progress - or if you prefer a hardware method toggle two different pins and use an oscilloscope).
My guess is that there is something wrong with the CAN peripheral communication.
thanks, Reinhard. the queue id is the same, and the calls to both functions is ok , i'm pretty sure about this, but cannot figure out why osMessageGet is called one more time than osMessagePut as I wrote ahead.
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