STM32F4 UART IRQ issue

[vivek23]

Posted on January 22, 2015 at 10:07

Hi,

I am trying to receive RF packet using USART1 IRQ, using below code. But packets are missing in the receive end. My point here is sometimes i will receive packets and the received packet is completely valid, i mean all received bytes are perfect. But I am expecting interrupt IRQ to be called many times. but thats not happening here. Can any one please suggest me is my IRQ function is valid ? void USART 1 _IRQHandler(void) { char c; uint 8 _t rByte= 0 ,lsb= 0 ,msb= 0 ,rCnt= 0 ; c=USART_ReceiveData(USART 1 ); switch(rByte) { case 0: if(c==PACKET_DELIMETER) { received_String[rCnt++]=c; //first byte copied to array rByte= 1 ; } break; case 1: msb=c; //Second byte copied to array received_String[rCnt++]=msb; rByte= 2 ; break; case 2: lsb=c; // 3 rd byte copied to array received_String[rCnt++]=lsb; rByte= 3 ; break; case 3: if(c==ZB_API_RECEIVEPACKET) { received_String[rCnt]=c; for(rCnt= 4 ;rCnt<lsb+ 1 ;rCnt++) { received_String[rCnt]=c; // whole packet will be received at this point } rByte= 4 ; } break; case 4: if(received_String[ 15 ]==g_ch_indx && received_String[ 16 ]==g_frame_Id) { g_bOK= 1 ; g_nei_id = received_String[ 17 ]; } break; default : break; } }

[Tesla DeLorean]

Posted on January 22, 2015 at 11:07

Unreadable wall of code here, please try again with the code, and explanation of the problem.

[vivek23]

Posted on January 22, 2015 at 11:48Sorry for the wrong format. Now I have corrected it. Please suggest is the code can work as expected.

[waclawek.jan]

Posted on January 22, 2015 at 11:48

You assume that the variables you use are static, i.e. don't change between successive invocations of the routine, but you don't declare them as such.

JW

[vivek23]

Posted on January 23, 2015 at 02:26 Hi, Thanks for your reply. But I tried even declaring my variables as static. Still i cannot receive my data packets contentiously. Many packets are missing in between. All the packets are reaching my receiving device. But interrupt IRQ happening very few times.

volatile char c; // tried by declaring c as volatile char and char
uint
8
_t lsb=
0
,msb=
0
;
static
uint
8
_t rByte=
0
,rCnt=
0
; // 
static
variables