Serial Port won't reset

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Fergal

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Sep 7, 2009, 5:22:07 PM9/7/09
to Bifferboard
Ok,

So I was following the guide to setup the 3g modem on BB.
Had flashed the kernel and copied the new rootfs to the usb stick.
Booted up BB a couple of times without the 3g stick, everything seemed
ok.
Serial port was working ok and console was there, could issue commands
etc.
Rebooted again with 3g modem in the hub and everything was also ok
with the serial port.
Serial port was working ok and console was there, could issue commands
etc.
Powered off and decided for some reason to swap the usb stick and 3g
modem to different ports on the hub.
Powered up and after this nothing on the serial console.

Have checked the cable and its definitley ok.
Tried different combinations without 3g modem, hub, and just usb stick
connected direct to BB. Nothing on the console.

Followed the advice for resetting the serial port,
http://sites.google.com/site/bifferboard/Home/howto/reset-serial-port
No luck there.

Am very much a linux novice so no idea what to try next.

Any advice much appreciated
Fergal

Nelson Neves

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Sep 7, 2009, 5:55:22 PM9/7/09
to biffe...@googlegroups.com
Why don't you try to access Bifferboard over Ethernet connection, say like, 1st use telnet to bifferboard IP. You will have direct access, then I would recommend to set the new password, requires to run command:
> passwd

After that, exit telnet and start using SSH connection (more secure connection and better way to access bifferboard - will also support file transfer over scp protocol). For the ssh connection the user should be root and the pass whatever you have set over previous command.

From a windows machine you can use putty to access BB over SSH . WinScp is another useful program for file transfer. From a Linux machine no need to install, SSH client is already present.

Regarding your problem, you may be using a USB->Serial cable and probably got a bit confused with your 3G modem (it also uses /dev/USBtty internally to mount the serial modem) - just a thought!

Regards,

Nelson.

ps: if you get your 3g modem to work with your mobile ISP, can you please give me feedback of the required changes for the 3G connection (to update the wiki).

bifferos

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Sep 7, 2009, 6:17:12 PM9/7/09
to Bifferboard
You say you checked the cable - how did you do that?
Have you tested this without anything connected to the BB at all (not
even USB flash)?

thanks,
Biff.

On Sep 7, 10:22 pm, Fergal <ferga...@gmail.com> wrote:
> Ok,
>
> So I was following the guide to setup the 3g modem on BB.
> Had flashed the kernel and copied the new rootfs to the usb stick.
> Booted up BB a couple of times without the 3g stick, everything seemed
> ok.
> Serial port was working ok and console was there, could issue commands
> etc.
> Rebooted again with 3g modem in the hub and everything was also ok
> with the serial port.
> Serial port was working ok and console was there, could issue commands
> etc.
> Powered off and decided for some reason to swap the usb stick and 3g
> modem to different ports on the hub.
> Powered up and after this nothing on the serial console.
>
> Have checked the cable and its definitley ok.
> Tried different combinations without 3g modem, hub, and just usb stick
> connected direct to BB. Nothing on the console.
>
> Followed the advice for resetting the serial port,http://sites.google.com/site/bifferboard/Home/howto/reset-serial-port

Fergal

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Sep 7, 2009, 7:07:02 PM9/7/09
to Bifferboard
Re checking serial cable: connected to minicom, then checked voltage
between Tx and Gnd, press a key and notice a drop in voltage.
then to verify Rx, connect tx to rx and type on keyboard, its echoed
on minicom.

Also checked cable with another board (not BB) which I know definitely
works and I get the normal output on minicom.

@Nelson: dont have access to a router at the moment and can't seem to
figure out how to connect my vista laptop (or using virtualbox
ubuntu ) directly to BB - any advice?
Will definitelty let you know if I get the 3g modem working.

So it would seem I need to reflash BB with the normal BB image via the
ethernet connection.
Any advice on how to set that up with a direct network cable from my
laptop to BB? (maybe this is a stupid question but haven't been
successful in ever connecting to BB directly through network cable).

thanks
Fergal

Andrew Scheller

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Sep 7, 2009, 7:19:33 PM9/7/09
to biffe...@googlegroups.com
[snip]

> Also checked cable with another board (not BB) which I know definitely
> works and I get the normal output on minicom.

Hmmmm... the other thing to try is repeatedly pressing Esc in the
serial console immediately after powering on the bifferboard - it
might just be that you've accidentally turned off bootloader serial
output. Pressing Esc brings up the biffboot options screen.

> @Nelson: dont have access to a  router at the moment and can't seem to
> figure out how to connect my vista laptop (or using virtualbox
> ubuntu ) directly to BB - any advice?

If you don't have a router, you can connect BB directly to your laptop
with a crossover ethernet cable.

Lurch

bifferos

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Sep 7, 2009, 7:31:59 PM9/7/09
to Bifferboard
On Sep 8, 12:07 am, Fergal <ferga...@gmail.com> wrote:
> Re checking serial cable: connected to minicom, then checked voltage
> between Tx and Gnd, press a key and notice a drop in voltage.
> then to verify Rx, connect tx to rx and type on keyboard, its echoed
> on minicom.

OK, so your cable is working.

About my 2nd question, probably obvious, but I have to ask again: Do
you get nothing out of the serial connection even when nothing is
connected to the USB and nothing is connected to the ethernet and you
then power on? Just trying to remove as many variables as possible
here. It seems that most of what you wrote in your first email is
largely irrelevant and what you could really just say is "My serial
port doesn't work" and forget the 3G stuff. Hope I am understanding
correctly.

Assuming you switch on the BB, and you have a link to the serial port,
then sending <ESC> just after the power comes on should drop you in
the bootloader prompt. If it doesn't then it's due to one of the
following:

- Your baud rate/coms parameters are not set correctly in minicom
- You board is not functioning
- Your serial port has been damaged

The most likely one I'm guessing now, is the first one - baud rate
incorrect, so the BB doesn't receive the '<ESC>' character, and you
never get the Biffboot console.

regards,
Biff.

bifferos

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Sep 7, 2009, 7:35:36 PM9/7/09
to Bifferboard
Oh yes... as Andrew says, the other possibility is that you're not
pressing <ESC> fast enough, or maybe you're pressing it too fast. You
normally have about 2 seconds to hit it after power-on.

Fergal

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Sep 7, 2009, 7:49:17 PM9/7/09
to Bifferboard
Yeah should have just said "serial port not working"

Baud rate is ok 115200
Setup is ok also 115200, 8,N,1, and no flow control. This hasn't
changed from when serial port was working and outputting to minicom.

Have tried just powering BB on its own a number of time, nothing on
minicom.
Retried and pressed ESC as described a number of times, no luck
either.

Will locate a crossover ethernet cable tomorrow and try that.

When you power on BB, should the blue led be permanently on?

thanks

Nelson Neves

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Sep 7, 2009, 8:16:53 PM9/7/09
to biffe...@googlegroups.com
Please note that connecting Bifferboard over crossover cable to your laptop will work OK provided that you change Bifferboard Ethernet configurations to set a fixed IP (you will not have dhcp support on your laptop, so you need to give BB a fixed IP).

For that you will need to connect the USB PEN (rootfs) to a linux computer (or vmware/virtualbox) and edit:
> sudo nano /etc/config/network/

<copy from here>
# Copyright (C) 2006 OpenWrt.org
config  interface       loopback
        option  ifname  lo
        option  proto   static
        option  ipaddr  127.0.0.1
        option  netmask 255.0.0.0

config  interface       lan
        option  ifname  eth0
        option  proto   static
        option  ipaddr  192.168.1.66
        option  netmask 255.255.255.0
        option  gateway 192.168.1.254
        option  dns     208.67.222.222
<to here>

This will set your BB with 192.168.1.66 IP.

Regards,
Nelson.

Nelson Neves

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Sep 7, 2009, 8:21:00 PM9/7/09
to biffe...@googlegroups.com
sorry,

> sudo nano /etc/config/network/

I mean:

> sudo nano ROOTFS_PENUSB_PATH/etc/config/network/

to connect over ssh (only after making the required telnet passwd change) you can use this windows app:
http://haanstra.eu/putty/
(over data, autologin user -> use root)

Regards,
Nelson.

Fergal

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Sep 17, 2009, 6:26:55 PM9/17/09
to Bifferboard
Finally located a crossover cable, took a while.

So bifferboard is definitely working and booting ok.

Based on what Biff said above, with network cable removed and serial
cable attached, pressing <ESC> does not drop me into the biffboot
console.

Settings have been checked and are correct
Serial cable has been checked and is working

Is there any other way to check if the serial port on the bifferboad
has been damaged?

Thanks
Fergal

Andrew Scheller

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Sep 17, 2009, 6:37:21 PM9/17/09
to biffe...@googlegroups.com
> Finally located a crossover cable, took a while.
>
> So bifferboard is definitely working and booting ok.
>
> Is there any other way to check if the serial port on the bifferboad
> has been damaged?

Are you able to connect to your bifferboard using ethernet i.e. using SSH?
If you are, you could try sending data to your bifferboard's serial
port from within linux, and seeing if it 'comes out the other end' ?

Lurch

Nelson Neves

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Sep 17, 2009, 6:59:45 PM9/17/09
to biffe...@googlegroups.com
From my Linux machine (from serial program - over serial cable) I have to explicit send the Code for the ESC key in hexadecimal mode, think that is the code 0x1B.
Don't know if it helps, not quite understanding what is wrong, mine works pretty well (and I have 3 boards).

Regards,
Nelson.

Fergal

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Sep 17, 2009, 7:31:53 PM9/17/09
to Bifferboard
@ Andrew - Yes I can connect no problem to BB over SSH. Tried your
suggestion using
echo -n "test">/dev/ttyS0
nothing shows up on minicom

@ Nelson - problem is I cannot get the serial port to work. It was
working but now it is not.
Otherwise BB functions ok

bifferos

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Sep 17, 2009, 8:00:17 PM9/17/09
to Bifferboard
If you have a working system it would be interesting to also see how
the device has been recognised by Linux, i.e. post the bootlog output
from dmesg.

thanks,
Biff.

Fergal

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Oct 5, 2009, 3:56:38 PM10/5/09
to Bifferboard
Sorry been away for a while, here is the dmesg output,

login as: root
ro...@192.168.20.2's password:


BusyBox v1.11.3 (2009-05-08 21:37:54 BST) built-in shell (ash)
Enter 'help' for a list of built-in commands.

Biffroot v1.4
=============
Bifferboard profile based on OpenWrt Kamikaze.
See http://www.bifferos.com for info.
root@OpenWrt:~# dmesg
[ 0.000000] Linux version 2.6.27.5 (wrt@cent) (gcc version 4.1.2)
#1 Fri May 8 21:56:57 BST 2009
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] BIOS-e801: 0000000000000000 - 000000000009f000
(usable)
[ 0.000000] BIOS-e801: 0000000000100000 - 0000000002000000
(usable)
[ 0.000000] Early serial console at I/O port 0x3f8 (options
'115200')
[ 0.000000] console [uart0] enabled
[ 0.000000] last_pfn = 0x2000 max_arch_pfn = 0x100000
[ 0.000000] kernel direct mapping tables up to 2000000 @ 7000-13000
[ 0.000000] 0MB HIGHMEM available.
[ 0.000000] 32MB LOWMEM available.
[ 0.000000] mapped low ram: 0 - 02000000
[ 0.000000] low ram: 00000000 - 02000000
[ 0.000000] bootmap 00001000 - 00001400
[ 0.000000] (6 early reservations) ==> bootmem [0000000000 -
0002000000]
[ 0.000000] #0 [0000000000 - 0000001000] BIOS data page ==>
[0000000000 - 0000001000]
[ 0.000000] #1 [0000100000 - 00002bb1e0] TEXT DATA BSS ==>
[0000100000 - 00002bb1e0]
[ 0.000000] #2 [00002bc000 - 00002be000] INIT_PG_TABLE ==>
[00002bc000 - 00002be000]
[ 0.000000] #3 [000009f000 - 0000100000] BIOS reserved ==>
[000009f000 - 0000100000]
[ 0.000000] #4 [0000007000 - 000000e000] PGTABLE ==>
[0000007000 - 000000e000]
[ 0.000000] #5 [0000001000 - 0000002000] BOOTMAP ==>
[0000001000 - 0000002000]
[ 0.000000] Zone PFN ranges:
[ 0.000000] DMA 0x00000000 -> 0x00001000
[ 0.000000] Normal 0x00001000 -> 0x00002000
[ 0.000000] HighMem 0x00002000 -> 0x00002000
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[2] active PFN ranges
[ 0.000000] 0: 0x00000000 -> 0x0000009f
[ 0.000000] 0: 0x00000100 -> 0x00002000
[ 0.000000] On node 0 totalpages: 8095
[ 0.000000] free_area_init_node: node 0, pgdat c027cfa0,
node_mem_map c1000000
[ 0.000000] DMA zone: 3967 pages, LIFO batch:0
[ 0.000000] Normal zone: 4064 pages, LIFO batch:0
[ 0.000000] Allocating PCI resources starting at 10000000 (gap:
2000000:fe000000)
[ 0.000000] Built 1 zonelists in Zone order, mobility grouping on.
Total pages: 8031
[ 0.000000] Kernel command line: console=uart,io,0x3f8 init=/etc/
preinit root=/dev/sda1 rootwait
[ 0.000000] Initializing CPU#0
[ 0.000000] PID hash table entries: 128 (order: 7, 512 bytes)
[ 0.000000] Console: colour dummy device 80x25
[ 0.000000] console handover: boot [uart0] -> real [ttyS0]
[ 0.000000] Dentry cache hash table entries: 4096 (order: 2, 16384
bytes)
[ 0.000000] Inode-cache hash table entries: 2048 (order: 1, 8192
bytes)
[ 0.000000] Memory: 30272k/32768k available (1178k kernel code,
2104k reserved, 366k data, 112k init, 0k highmem)
[ 0.000000] virtual kernel memory layout:
[ 0.000000] fixmap : 0xfffed000 - 0xfffff000 ( 72 kB)
[ 0.000000] pkmap : 0xff800000 - 0xffc00000 (4096 kB)
[ 0.000000] vmalloc : 0xc2800000 - 0xff7fe000 ( 975 MB)
[ 0.000000] lowmem : 0xc0000000 - 0xc2000000 ( 32 MB)
[ 0.000000] .init : 0xc0286000 - 0xc02a2000 ( 112 kB)
[ 0.000000] .data : 0xc0226944 - 0xc02824f8 ( 366 kB)
[ 0.000000] .text : 0xc0100000 - 0xc0226944 (1178 kB)
[ 0.000000] Checking if this processor honours the WP bit even in
supervisor mode...Ok.
[ 0.000000] CPA: page pool initialized 1 of 1 pages preallocated
[ 0.001000] Calibrating delay loop... 47.10 BogoMIPS (lpj=23552)
[ 0.021006] Mount-cache hash table entries: 512
[ 0.025008] CPU: 486
[ 0.026008] Checking 'hlt' instruction... OK.
[ 0.031009] Freeing SMP alternatives: 0k freed
[ 0.037011] net_namespace: 288 bytes
[ 0.042013] NET: Registered protocol family 16
[ 0.049015] Bifferboard: Init GPIO chip...
[ 0.050016] Mapping GPIO Bank #1 (11 -> 0)
[ 0.052016] Mapping GPIO Bank #1 (13 -> 1)
[ 0.053016] Mapping GPIO Bank #1 (9 -> 2)
[ 0.054017] Mapping GPIO Bank #1 (12 -> 3)
[ 0.055017] Mapping GPIO Bank #1 (15 -> 4)
[ 0.056017] Mapping GPIO Bank #1 (16 -> 5)
[ 0.057018] Bifferboard: Chip init done.
[ 0.059018] PCI: Using configuration type 1 for base access
[ 0.086027] SCSI subsystem initialized
[ 0.090028] usbcore: registered new interface driver usbfs
[ 0.092029] usbcore: registered new interface driver hub
[ 0.095030] usbcore: registered new device driver usb
[ 0.099031] PCI: Probing PCI hardware
[ 0.101032] PCI: Probing PCI hardware (bus 00)
[ 0.102032] PCI: 0000:00:08.0 reg 10 io port: [e800, e8ff]
[ 0.102032] PCI: 0000:00:08.0 reg 14 32bit mmio: [d1900000,
d19000ff]
[ 0.103032] PCI: 0000:00:09.0 reg 10 io port: [0, ff]
[ 0.103032] PCI: 0000:00:09.0 reg 14 32bit mmio: [0, ff]
[ 0.103032] PCI: 0000:00:0a.0 reg 10 32bit mmio: [d5900000,
d5900fff]
[ 0.103032] PCI: 0000:00:0a.1 reg 10 32bit mmio: [d4900000,
d4900fff]
[ 0.129063] bus: 00 index 0 io port: [0, ffff]
[ 0.130727] bus: 00 index 1 mmio: [0, ffffffff]
[ 0.131485] NET: Registered protocol family 2
[ 0.135062] IP route cache hash table entries: 1024 (order: 0, 4096
bytes)
[ 0.143063] TCP established hash table entries: 1024 (order: 1,
8192 bytes)
[ 0.144082] TCP bind hash table entries: 1024 (order: 0, 4096
bytes)
[ 0.145755] TCP: Hash tables configured (established 1024 bind
1024)
[ 0.146373] TCP reno registered
[ 0.153070] platform rtc_cmos: registered platform RTC device (no
PNP device found)
[ 0.160071] HugeTLB registered 4 MB page size, pre-allocated 0
pages
[ 0.163071] msgmni has been set to 59
[ 0.165064] io scheduler noop registered (default)
[ 0.258099] Serial: 8250/16550 driver4 ports, IRQ sharing enabled
[ 0.504184] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
[ 0.513184] <6>r6040: RDC R6040 NAPI net driver,version 0.20
(07Jan2009)
[ 0.514587] r6040 0000:00:08.0: setting latency timer to 64
[ 0.550196] Fixed MDIO Bus: probed
[ 0.552195] Driver 'sd' needs updating - please use bus_type
methods
[ 0.555199] ehci_hcd 0000:00:0a.1: EHCI Host Controller
[ 0.558198] ehci_hcd 0000:00:0a.1: new USB bus registered, assigned
bus number 1
[ 0.560193] ehci_hcd 0000:00:0a.1: irq 14, io mem 0xd4900000
[ 0.567204] ehci_hcd 0000:00:0a.1: USB 2.0 started, EHCI 1.00,
driver 10 Dec 2004
[ 0.571209] usb usb1: configuration #1 chosen from 1 choice
[ 0.573200] hub 1-0:1.0: USB hub found
[ 0.574667] hub 1-0:1.0: 2 ports detected
[ 0.783271] ohci_hcd: 2006 August 04 USB 1.1 'Open' Host Controller
(OHCI) Driver
[ 0.784288] ohci_hcd 0000:00:0a.0: OHCI Host Controller
[ 0.787280] ohci_hcd 0000:00:0a.0: new USB bus registered, assigned
bus number 2
[ 0.788932] ohci_hcd 0000:00:0a.0: irq 15, io mem 0xd5900000
[ 0.844293] usb usb2: configuration #1 chosen from 1 choice
[ 0.846288] hub 2-0:1.0: USB hub found
[ 0.848060] hub 2-0:1.0: 2 ports detected
[ 0.884305] usb 1-1: new high speed USB device using ehci_hcd and
address 2
[ 0.953326] Initializing USB Mass Storage driver...
[ 1.004342] usb 1-1: configuration #1 chosen from 1 choice
[ 1.016344] scsi0 : SCSI emulation for USB Mass Storage devices
[ 1.021346] usb-storage: device found at 2
[ 1.021346] usb-storage: waiting for device to settle before
scanning
[ 1.022431] usbcore: registered new interface driver usb-storage
[ 1.023869] USB Mass Storage support registered.
[ 1.026348] i8042.c: Warning: Keylock active.
[ 1.028928] serio: i8042 KBD port at 0x60,0x64 irq 1
[ 1.042350] TCP cubic registered
[ 1.044378] NET: Registered protocol family 17
[ 1.045993] Using IPI Shortcut mode
[ 1.054354] Waiting for root device /dev/sda1...
[ 6.025951] scsi 0:0:0:0: Direct-Access 4096MB flash
drive 1.0 PQ: 0 ANSI: 2
[ 6.033957] sd 0:0:0:0: [sda] 7897088 512-byte hardware sectors
(4043 MB)
[ 6.036329] sd 0:0:0:0: [sda] Write Protect is off
[ 6.037572] sd 0:0:0:0: [sda] Mode Sense: 00 00 00 00
[ 6.037572] sd 0:0:0:0: [sda] Assuming drive cache: write through
[ 6.043950] sd 0:0:0:0: [sda] 7897088 512-byte hardware sectors
(4043 MB)
[ 6.046201] sd 0:0:0:0: [sda] Write Protect is off
[ 6.047454] sd 0:0:0:0: [sda] Mode Sense: 00 00 00 00
[ 6.047454] sd 0:0:0:0: [sda] Assuming drive cache: write through
[ 6.048838] sda: sda1
[ 6.184002] sd 0:0:0:0: [sda] Attached SCSI removable disk
[ 6.191010] usb-storage: device scan complete
[ 6.217041] EXT2-fs warning: mounting unchecked fs, running e2fsck
is recommended
[ 6.219049] VFS: Mounted root (ext2 filesystem).
[ 6.223003] Freeing unused kernel memory: 112k freed
[ 6.754185] Warning: unable to open an initial console.
[ 13.531363] i2c /dev entries driver
[ 13.863469] gpio-proxy research driver (v1.0) by bifferos, loaded.
root@OpenWrt:~#

bifferos

unread,
Oct 5, 2009, 6:37:28 PM10/5/09
to Bifferboard
OK, seems like the software side is working fine so it must be the
hardware. Please get in touch off-list if you want to arrange to
return it.

cheers,
Biff.

On Oct 5, 8:56 pm, Fergal <ferga...@gmail.com> wrote:
> Sorry been away for a while, here is the dmesg output,
>
> login as: root
> r...@192.168.20.2's password:
>
> BusyBox v1.11.3 (2009-05-08 21:37:54 BST) built-in shell (ash)
> Enter 'help' for a list of built-in commands.
>
> Biffroot v1.4
> =============
> Bifferboard profile based on OpenWrt Kamikaze.
> Seehttp://www.bifferos.comfor info.
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