Stein, I am in the same boat!! I need to set the UART to 250k baud for DMX512 lighting <http://en.wikipedia.org/wiki/DMX512#Protocol>. According to your below math, this should be 16x oversampling and a divisor of 12 for me. I hope there is a way to set these values via command line and/or config files.
This stuff here is interesting, but I'm not sure how (or if) I can change these numbers? debian@vBBB20:/sys/devices/ocp.3/481a8000.serial/tty/ttyO4$ ls close_delay custom_divisor device iomem_base io_type line power type uevent closing_wait dev flags iomem_reg_shift irq port subsystem uartclk xmit_fifo_size debian@vBBB20:/sys/devices/ocp.3/481a8000.serial/tty/ttyO4$ sudo cat uartclk 48000000 debian@vBBB20:/sys/devices/ocp.3/481a8000.serial/tty/ttyO4$ sudo cat custom_divisor 0 Looks interesting, but not sure how to manipulate these things? Device Tree? DTC? Config files? I am watching this thread closely now. Thx! -frenchy On Saturday, November 15, 2014 2:23:28 PM UTC-5, [email protected] wrote: > > The AM335x Sitara processor has two registers, divisor high and divisor > low, where you can set the preferred divisor. > With the formula 'baudrate = clock / (over sampling x divisor)' you can > calculate the divisor for the desired baudrate. > There are 2 modes, 16x and 13x, for the over sampling. I will use the 16x > mode. > I want to have a baudrate of 100 kbps, so my divisor needs to be 30. This > gives an error of 0%. > You can find information about these registers at page 4270 in the > datasheet of the AM335x > > Does anyone know how I can set these registers? > > kind regards, > Stein > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
