I have tried to use minicom to open several of the uarts under /dev/
ttyO1 etc. At first I tried using my null modem cable to my PC
(through a level converter) but I wasn't getting any comms, so then I
tried my edge-detecting logic probe and I'm not getting any signal
from the TXD pins. I've triple checked to make sure I'm on the right
pins on the right header.
Someone mentioned the pinmux issue. I was hoping that since the pins
are named UART1_TXD etc that I would not have to muck with the mux
config. In any event I can't seem to find ANY bone specific info on
changing pinmux-ing. Bear in mind that while I am a software engineer
by trade I am new to the whole beagle world. I have searched and
searched and gleaned and gleaned and I think I need to look at the
bone uBoot sources to check or change the pinmux but I can't for the
life of me find it. Could somebody please provide a URL?
Has anybody else had success with the Bone UARTs? Could you please
describe your steps to win?
A howto on the subject of changing pinmux settings including steps to
get and build uboot would be radical.
Thanks,
Jeff
j.
> --
> You received this message because you are subscribed to the Google Groups "Beagle Board" group.
> To post to this group, send email to beagl...@googlegroups.com.
> To unsubscribe from this group, send email to beagleboard...@googlegroups.com.
> For more options, visit this group at http://groups.google.com/group/beagleboard?hl=en.
>
--
Given a choice between two theories, take the one which is funnier
I just talked to jkridner on #beagleboard and he suggested poking /sys/
kernel/debug/omap_mux/uart... Now I'm just trying to figure out what
the magic incantations to write to those files are ;)
On Dec 12, 10:56 pm, Jacek Radzikowski <jacek.radzikow...@gmail.com>
wrote:
> > For more options, visit this group athttp://groups.google.com/group/beagleboard?hl=en.
j.
> For more options, visit this group at http://groups.google.com/group/beagleboard?hl=en.
root@beaglebone:~# cat mux.py
#!/usr/bin/python
import os
import logging
DDR_IN = (1 << 5)
DDR_OUT = (0 << 5)
PULL_R_UP = (1 << 4)
PULL_R_DOWN = (0 << 4)
PULL_R_EN = (1 << 3)
PULL_R_DIS = (0 << 3)
uart1_pin_mux = [
('uart1_rxd', (0 | DDR_IN)),
('uart1_txd', (0)),
]
logging.basicConfig(level=logging.DEBUG)
for (fname, mode) in uart1_pin_mux:
logging.debug("%s = %s" % (fname, mode))
with open(os.path.join('/sys/kernel/debug/omap_mux', fname), 'wb') as
f:
f.write("%X" % mode)
On Dec 13, 12:15 am, Jacek Radzikowski <jacek.radzikow...@gmail.com>
wrote:
Thanks!
(1 << 3) takes the number 1 and bit-shifts it 3 places to the left, so
b00001 becomes b01000. Then by binary-or-ing one or more of those
values together you can create a bitmask in a way that clearly
communicates what's going on. You could just as easily do the math in
your head and say pinmux = 0x00000024 or whatever but it's much harder
to see what's going on there.
5 4 3 210
pinmux bits = W X Y ZZZ where
W = data direction bit
X = pull up/down bit
Y = pull enable
ZZZ = 3 bit mode number, 0-7
I more or less copied this code out of the bone uboot source file
board/ti/am335x/mux.c, ported it to python, made it write to debugfs
instead of directly to memory, and changed the bit names for clarity.
On Dec 13, 10:00 am, Charlie Fullerton <cwfullerton21...@gmail.com>
wrote:
var SerialPort = require("serialport").SerialPort ;
var serialPort = new SerialPort('/dev/ttyO1' , {baudrate : 9600} );
serial is successfully created, now writing
serialPort.write("TEST");
I get no data on header P9 pin 24 ( UART1_TX)
Maybe the mux is not correct configured for this ttyO1 so this data is
writed but does not goes to the P9 pin 24 ( UART1_TX)
Can u give me some lights to solve this
Tanks