2009-03-04 09:45:26     SPORT UART Emulation reading error

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2009-03-04 09:45:26     SPORT UART Emulation reading error

ThangarJ P (INDIA)

Message: 70370   

 

Dear All,

 

we are working in BF533-EZKit and uClinux Distribution Release 2008R1.5

 

we have enabled the SPORT UART Emulation in the Make menuconfig and also done the HW changes as per the EE191.

 

we have tested the basic testing. both transmiting and receiving works fine.

 

but the we couldnt succeeded with the read API from user space.

 

if we are calling  write API from user space with a buffer pointer and count then the data in the buffer is trasmitted sucessfully.

 

but at the same time we are calling the read API from user space then its returning -1 (open from O_NONBLOCK mode) even at the time of RX interrupt occuring.

 

if we call the read API in without nonblocking mode then it wont come out from that API after the data is received.

 

how can we read the data from userspace ?

 

we called open and read functions as like below

 

fd = open("/dev/ttySS1", O_NONBLOCK  | O_RDWR);

 

the open success with returning value 3.

 

value =read(fd,&buff[0],1);

 

but this is returning -1 while at the time of data receiving also.

 

 

 

Please provide your Suggestions.

 

 

 

With Regards,

 

Thangaraj

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2009-03-05 03:06:32     Re: SPORT UART Emulation reading error

Appalayagari Sreedhar (INDIA)

Message: 70412   

 

Hi,

 

I am Sreedhar, Collegue of Thangaraj. He is on leave. can anyone has some clue to the above problem?. please reply me back if you require more information.

 

Thanks, Sreedhar.

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2009-03-10 08:58:05     Re: SPORT UART Emulation reading error

Appalayagari Sreedhar (INDIA)

Message: 70694   

 

Hi,

 

Anyone has some clue about the above problem.

 

Thanks, Sreedhar.

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