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 11:48

Sorry 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