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Uboot baudrate

Posted: Wed Nov 25, 2015 9:39 pm
by josephj
Hi,
I was just wondering if it was possible to change the baudrate for uboot? ( I need to set it lower to 19200 for the project ).

I've tried "setenv baudrate 19200" but the confirmation prompt that comes up after doesn't work at the new baud. To continue I need to set kermit back to 57600bps.
If I saveenv, then restart, printenv shows the new baudrate but the console still operates at the old baudrate (57600). Is there a way to change it?

Also does the openwrt take the console settings from uboot or should I compile the settings into openwrt?

Thanks

Re: Uboot baudrate

Posted: Thu Nov 26, 2015 10:04 am
by Vonger
As I know current driver only support 57600.

Re: Uboot baudrate

Posted: Thu Nov 26, 2015 2:55 pm
by noblepepper
Certainly possible, not easily though.

I believe the das Uboot baudrate is compiled in so you would need to change the sources and recompile.

Here is some info but you need to be prepared for writing the flash chip directly. I bricked my VoCore several times and had to rewrite the flash to revive it.

A quick search of the source gave me this:

Code: Select all
grep -r 57600 ./*
./board/rt2880/include/uart.h:#define UART_BAUD_57600      ((uint32)((SYS_CLK_KHZ * 1000) / (16 * 57600)))
./board/rt2880/include/uart.h:   B57600,
./doc/README.db64360:Check that the UART baud rate is configured to 57600 and 115200, and check:
./doc/README.db64460:Check that the UART baud rate is configured to 57600 and 115200, and check:
./include/configs/rt2880.h:#define CONFIG_BAUDRATE      57600
./include/configs/rt2880.h:#define CFG_BAUDRATE_TABLE   { 9600, 19200, 38400, 57600, 115200 }


There may be more than one change needed but this looks like a good starting place:
Code: Select all
./include/configs/rt2880.h:#define CONFIG_BAUDRATE      57600