Serial bootloader and boot console without FTDI chip?

I've got a BeagleBone with what appears to be a non-working FTDI chip.

What'd be the best way to get serial boot messages, bootloader, and console off of this thing without using the broken FTDI chip?

After looking through the manual, schematic, and docs, it appears that UART1 is brought out to the 40-pin headers P8 and P9, but UART0 does not appear to be available anywhere else except through the non-working FTDI chip.

If that's the case, then I'd have to use UART1. I suppose I could reconfigure the kernel (or u-boot maybe) to seed the kernel with boot arguments to use console=ttyO1 (which I'm guessing is UART1) instead of tty00, but I might also have to hack the kernel to set the default mux state of those pins too.

I'm definitely not sure how to make the bootloaders use the other serial port, in case I might need access to that, though.

-ken

What'd be the best way to get serial boot messages, bootloader, and console off of this thing without using the broken FTDI chip?

After looking through the manual, schematic, and docs, it appears that UART1 is brought out to the 40-pin headers P8 and P9, but UART0 does not appear to be available anywhere else except through the non-working FTDI chip.

I currently use UART1 on some of my BeagleBones. It works nicely (I
dislike the FTDI chip, but mine still work). You'll need to convert
standard RS232 signals (+/- 12V) down to 3.3V logic for use with the
expansion connectors, something like the Sparkfun converter works well
for me [1]. It doesn't bring out the flow control or other fun pins,
but RX and TX is usually good enough.

[1]: SparkFun RS232 Shifter - SMD - PRT-00449 - SparkFun Electronics

If that's the case, then I'd have to use UART1. I suppose I could reconfigure the kernel (or u-boot maybe) to seed the kernel with boot arguments to use console=ttyO1 (which I'm guessing is UART1) instead of tty00, but I might also have to hack the kernel to set the default mux state of those pins too.

Yes, you'll need to update u-boot. You "should" be able to simply pass
the new tty01 console variable to the kernel at boot time without
recompiling, but you "may" need to recompile the kernel if the kernel
is setting those pins to be mux'ed to something other than UART1
(may depend on what kernel source you're using).

I'm definitely not sure how to make the bootloaders use the other serial port, in case I might need access to that, though.

For u-boot, something like the below patch (note, I'm not using the
am335x-evm config, I copied and modified it and mine is called
beaglebone.h instead, so you can't directly apply this, but it should
give you a decent idea of needs to be done). I started with a copy of
the Arago am335x u-boot repo [2] but it has since been modified a bit:

[2]: http://arago-project.org/git/projects/?p=u-boot-am33x.git;a=summary

From 6263be7a3ea785ef9cf7d104263846b4eeb7df80 Mon Sep 17 00:00:00 2001