NIOS Uart : change baud rate

I believe the UART hardware has to be configured to allow for adjustable baud rates. Unless you remember doing this, in SOPC Builder, I believe the default is off.

Cheers,

- slacker

For being able of modifying the UART baudrate, check theese:

- In SOPCBuilder open the editor dialog for the UART component in your system (double click on it), there is a parametter for including an UART bauderate register;

- Make sure that you're not using the reduced footprint driver's HAL mode in your system library;

- Include this define ALTERA_AVALON_UART_USE_IOCTL in the compiler preprocessor configuration settings for your system library and recompile it;

- Add the includes# include <sys/ioctl.h> and# include <sys/termios.h> to your source file;

Now you can use code like this for changing the uart speed:

struct termios termios;

int res = ioctl( uartfd, TIOCMGET, &termios );

termios.c_ispeed = your_new_bauderate;

termios.c_ospeed = your_new_bauderate;

res = ioctl( uartfd, TIOCMSET, &termios );

The above code can be used provided that you opened the uart using code like:

int uartfd;

uartfd = open( your_uart_device_name, O_RDWR | O_NONBLOCK | O_NOCTTY );

if (uartfd == -1)

{

printf( "FATAL ERROR with uart \"%s\"\r\n", uart_name );

return 1;

}

The options are ORed according to my needs, which could be a little bit different from yours.

Thanks very much for the precise response.

It works. I wasn&#39;t aware of the ALTERA_AVALON_UART_USE_IOCTL.

Cheers,

-- Richard --

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originally posted by vlorenzo@Jan 14 2006, 11:05 AM

for being able of modifying the uart baudrate, check theese:

- in sopcbuilder open the editor dialog for the uart component in your system (double click on it), there is a parametter for including an uart bauderate register;

- make sure that you&#39;re not using the reduced footprint driver&#39;s hal mode in your system library;

- include this define altera_avalon_uart_use_ioctl in the compiler preprocessor configuration settings for your system library and recompile it;

- add the includes# include <sys/ioctl.h> and# include <sys/termios.h> to your source file;

now you can use code like this for changing the uart speed:

struct termios termios;

int res = ioctl( uartfd, tiocmget, &termios );

termios.c_ispeed = your_new_bauderate;

termios.c_ospeed = your_new_bauderate;

res = ioctl( uartfd, tiocmset, &termios );

the above code can be used provided that you opened the uart using code like:

int uartfd;

uartfd = open( your_uart_device_name, o_rdwr | o_nonblock | o_noctty );

if (uartfd == -1)

{

printf( "fatal error with uart \"%s\"\r\n", uart_name );

return 1;

}

the options are ored according to my needs, which could be a little bit different from yours.

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--- quote end ---

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--- Quote Start ---

For being able of modifying the UART baudrate, check theese:

- In SOPCBuilder open the editor dialog for the UART component in your system (double click on it), there is a parametter for including an UART bauderate register;

- Make sure that you're not using the reduced footprint driver's HAL mode in your system library;

- Include this define ALTERA_AVALON_UART_USE_IOCTL in the compiler preprocessor configuration settings for your system library and recompile it;

- Add the includes# include <sys/ioctl.h> and# include <sys/termios.h> to your source file;

Now you can use code like this for changing the uart speed:

struct termios termios;

int res = ioctl( uartfd, TIOCMGET, &termios );

termios.c_ispeed = your_new_bauderate;

termios.c_ospeed = your_new_bauderate;

res = ioctl( uartfd, TIOCMSET, &termios );

The above code can be used provided that you opened the uart using code like:

int uartfd;

uartfd = open( your_uart_device_name, O_RDWR | O_NONBLOCK | O_NOCTTY );

if (uartfd == -1)

{

printf( "FATAL ERROR with uart \"%s\"\r\n", uart_name );

return 1;

}

The options are ORed according to my needs, which could be a little bit different from yours.

--- Quote End ---

Hi,

Regarding the sentence : Include this define ALTERA_AVALON_UART_USE_IOCTL in the compiler preprocessor configuration settings for your system library and recompile it;

Can you please explain how its done?

Thanks