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 } }