about programable UART Baudrate

ffone13,

There is an ioctl call to set the baud rate etc for the UART. If you look in the manual for the UART n2cpu_nii51010.pdf and look under the software programming model there is a section in here on ioctl which is where you should start.

hello rugbybloke,

could you look at the following code that change the baudrate?

in the sopc builder i have set the option that divisor can be change.

and the result is when execute:

if (fd->dev->ioctl)

{

rc = fd->dev->ioctl(fd, req, arg);

}

it stop!

/********************************************************/

int main (void)

{

char* msg = "hello world";

FILE* fp;

struct termios* term;

fp = fopen ("/dev/uart1", "w");

if (fp)

{

term->c_ispeed=B57600;

ioctl(fp, TIOCMSET, term);

fprintf(fp, "%s",msg);

fclose (fp);

}

return 0;

}

/********************************************************/

could you show me how to do?

thank you!

ffone13,

My guess is that you don't have the ioctl code included, the comment at the top of the driver gives you some clues

/*

* To reduce the code footprint of this driver, the ioctl() function is not

* included by default. If you wish to use the ioctl features provided

* below, you can do so by adding the option : -DALTERA_AVALON_UART_USE_IOCTL

* to CPPFLAGS in the Makefile (or through the Eclipse IDE).

*/

If this does not solve the problem then either step into the ioctl call to find the offending line, or set a breakpoint in the ioctl code inside the UART driver to find where the problem is.

Yes, you are right.I have finished it. but i find a bug that it seems to be in "static int alt_avalon_uart_tiocmset (alt_avalon_uart_dev* dev, struct termios* term) " function

of the altera_avalon_uart.c .

IOWR_ALTERA_AVALON_UART_DIVISOR(dev->base, ((dev->freq/speed) - 1)); the speed should be

dev->termios.c_ispeed, i think. because firstly speed = dev->termios.c_ispeed; is the original value.

thank you for reply!

ffone,

Looks like you're right thanks for the tip