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1  Hardware and U-Boot firmware / U-Boot stuff / Re: Kernel not using console= when booting on: May 20, 2012, 11:44:03 AM
Still no reply on this?  I tried again to see if I can figure out what the heck is happening, but still can't.
This issue appears to be the same as mine: http://www.plugcomputer.org/plugforum/index.php?topic=6068.0

I tried to connect using all the known baud rates, and none of them provided a readable console.
I used the SheevaPlug installer, and the kernel provided with it, if that means anything.

I plan on flashing the most recent kernel to see if that resolves the issue.

Linux seems to boot just fine, as it seems, just the console output doesn't seem to be working. Sad
2  Linux Stuff / Kernel / Re: Really funky characters when booting kernel on: May 20, 2012, 11:14:44 AM
Did you find a solution to this?  I have the exact same issue, and am unsure how to proceed. Here is my unanswered post:
3  Hardware and U-Boot firmware / U-Boot stuff / Kernel not using console= when booting on: March 20, 2012, 01:03:40 PM
When I boot my plug and watch the boot process via 'cu', u-boot is fine, but as soon as it loads the kernel, it shows only gibberish.

This is a new plug, which I am in the process of setting up.  I am using the kernel image from the sheeva installer.

Here is my current bootargs and bootcmd:

bootargs=console=ttyS0,115200 mtdparts=orion_nand:0x400000@0x100000(uImage),0x1fb00000@0x500000(rootfs) ubi.mtd=1 root=ubi0:rootfs rootfstype=ubifs
bootcmd=nand read.e 0x00800000 0x00100000 0x00400000; bootm 0x00800000

The system itself is working, and it appears that the console is not being set correctly.  Although it is clearly passing the correct console= information.  I verified this from many sources.

Has anyone else come across this issue and knows of a resolution?  Thanks.
4  General Category / General Discussion / Re: Remote X session vs VNC on: September 26, 2010, 09:21:25 PM
I know this topic is dead, but the more efficent way of starting a X application remotely through SSH would be:
ssh -Y kveroneau@plug xterm
If using Debian or Ubuntu, be sure this is added to your /etc/ssh/sshd_config file:
X11Forwarding yes
To use X forwarding on a Windows machine, you can download xwinlogon:

This package contains both the X server and SSH client with a tiny Cgywin system.

You could also install xrdp for example to connect to the plug using any RDP client.  RDP can resume sessions just like NX and VNC do:

You can even use xrdp to create a forwarding server.  For example, in your SOHO, forward the RDP port to xrdp.  When a user from outside the network connects to xrdp, they have a choice of what internal PC to connect to.  Connection types, include both RDP and VNC servers.  This would be a really easy and cost effective way to create a simple remote dial-in type VPN set-up for clients and workers to use.  It's a lot more simpler than using SSH to forward ports around your internal network and RDP has native encryption as well.
5  Linux Stuff / General Linux questions / question about wvdial and ppp on: September 26, 2010, 01:51:19 PM
I noticed that wvdial is not supported on the ARM platform, due to the missing getcontext API.  I have a 3G USB modem which works best with wvdial and has some issues with pppd.  It connects and dials using wvdial much quicker than when using pppd.  Unfortunately, I am not that great at pppd configuration, and this is why it does not connect correctly using pppd.

Is there a tool which can convert a wvdial.conf to pppd config files and chat files?  Or can someone here with pppd expertise help me develop an equivalent pppd config file out of a wvdial.conf file?

[Dialer Defaults]
Modem = /dev/ttyUSB0
ISDN = off
Modem Type = Analog Modem
Baud = 115200
Init = ATZ
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Init3 =
Init4 =
Init5 =
Init6 =
Init7 =
Init8 =
Init9 =
Phone = *99#
Phone1 =
Phone2 =
Phone3 =
Phone4 =
Dial Prefix =
Dial Attempts = 1
Dial Command = ATM1L3DT
Ask Password = off
Password = 1
Username = 1
Auto Reconnect = off
Abort on Busy = off
Carrier Check = on
Check Def Route = on
Abort on No Dialtone = on
Stupid Mode = on
Idle Seconds = 0
Auto DNS = on

This wvdial.conf file works perfectly with my 3G USB modem on my laptop.  Does pppd support stupid mode, if so how do I enable it?  As it is this mode which speeds up the connection process for wvdial.  Also my ISP does not use a user/pass for connecting to their 3G network, hence the reason they are set to '1'.

Thanks in advance for any help on pppd config.
6  Hardware and U-Boot firmware / U-Boot stuff / Re: mtdparts to reference "entire" NAND read-only on: September 26, 2010, 10:23:53 AM
Thanks for your reply, but I was thinking more along the lines of:

setenv mtdpartitions 'mtdparts=nand_mtd:0x1fb00000@0x000000(fullnand)'

I need help with the offset: 0x000000 and help with the size: 0x1fb00000

I am not sure of the Sheeva Plug's internal NAND layout, I could only imagine that 0x000000 is the beginning of NAND.  However, I am not sure what to set the size to.

This would make an mtd0 device in Linux referenced as "fullnand" which contains the entire NAND.  A device a plan to dd to an external drive.

Hope this explains my question more.  Thanks.
7  Hardware and U-Boot firmware / U-Boot stuff / mtdparts to reference "entire" NAND read-only on: September 26, 2010, 01:03:42 AM
I am wanting to test something out, but I need to be-able to reference the entire NAND in the plug as a whole in Linux.

eg.  mtd0 = uboot+uImage+rootfs

But, I also want it to be available as read-only, just so I don't break anything.

What would I use as a mtdparts parameter for this?  Oh, and I won't be booting from NAND obviously while doing this.

8  Linux Stuff / General Linux questions / Re: How to clone a SheevaPlug? on: September 26, 2010, 12:55:29 AM
An efficient way of cloning SheevaPlugs is over a network using SSH and Pipes.

For this to work, you will need to have a network configured initrd booting from either a storage device or TFTP.

This solution would work for currently configured plugs in Sheeva_Installer, but you need to quickly update a bunch of plugs without using the USB key in each plug all over again...

Make a special host initrd, and then guest initrds to make it even simpler.  Boot your development plug into the host initrd image and mount the UBIFS in say /mnt, and make sure the SSH service is running.

Boot a production plug into the guest initrd which will automatically SSH to the host plug with a static IP.

SSH example command: ssh -n root@hostplug 'cd /mnt; tar zcvf - *' | tar zxvf -

Make the guest plug do a UBIATTACK, MOUNT, and CD into the destination directory before running the above SSH.  You may also want to run the UBIFORMAT commands as well.

Feel free to remove the 'z' parameter in TAR if your network is very very fast, as this will speed up the process.

I would never recommend transferring a LIVE file system, one which has been mounted via bind, as this may cause some applications and services to act funny.  I tend to only TAR Linux file systems which have been safely halted to have the best possible state when cloning using tarballs.  But that's just my personal phobia.

Overall, if an initrd is scripted right, you could adapt the SheevaInstaller to obtain the rootfs.tar.gz from an SSH source such as this for installing fresh off the shelf plugs.  Be sure to place your current uImage on the USB stick as well.

However, you can easily burn the TFTP'd uImage to the NAND before loading your guest initrd to clone the plug.  There are also u-boot commands for running special scripts from a TFTP which could automate the u-boot upgrade process and avoid using OpenOCD completely.  If you make the u-boot NAND partition visible in the host and guest initrd systems, you could easily transfer the entire u-boot binary and environment over the network and burn it directly to the NAND of the new plug!

For an even bigger kicker, when booting your custom guest initrd, make the MTD partition one huge single partition which can be accessed under Linux.  Use the SSH piping above to transfer an exact 512MB image over the network and burn it on a new plug!!!  Now that's mass-production at it's best.  For this, it might even be best to have the 512MB image stored on a speedy server machine to serve the images to all the hungry guest plugs to feed from.

In effect, if you choose the last option, for each new plug you purchase all you need to do is:

1.  Plug in your pre-configured USB stick with kernel and initrd into the new plug.
2.  Boot the plug using the USB stick's kernel and initrd.
3.  Wait while the initrd system transfers the entire 512MB NAND image from the server/devplug and burns it.
4.  Reboot the plug and enjoy the exactly cloned plug(u-boot, environment, mtdparts, etc...)

Hope this helps anyone who need to mass-produce plugs for the market.
9  Hardware and U-Boot firmware / Hardware / Does a 3G USB modem require additional power after network registration? on: September 25, 2010, 04:40:16 PM
I have a HUAWEI E182 USB HSPA+ Modem, which works wonders on my Linux laptop, and I am attempting to get it working on the SheevaPlug.  The Plug's kernel detects it fine, however when I enter in my PIN using comgt, the light flashes blue for just a split second confirming registration on the network then goes back to green.

Since I am connecting to the plug using cu, I can see the various kernel output, like it being inserted and detected.  The output is no different than from my laptop.  comgt detects the device with no problems, but then constantly waits for network registration.

I am guessing that it draws additional power from USB when turning on the cellular radio, so when it cannot draw more power, the 3G chip just turns itself back off.  This is very unfortunate, as an external power source is needed in order for the plug to connect to a 3G network to provide remote data.

Keep this in mind when developing remote applications which may just use solar energy for example, you may need to also supply the 3G modem with it's own power source.

Does WiFi act the same way?  When WiFi powers up it's radio, does it also draw more power, and which USB WiFi dongles would work best?
10  Hardware and U-Boot firmware / Hardware / Replaced SheevaPlug power supply with external adapter(pics, howto) on: September 25, 2010, 04:17:45 PM
So in a previous post I noted that my SheevaPlug's PSU was dead, today I went out to a local electronics store and purchased 3 items which I used to replace the PSU with an external AC-DC adapter.

Finished product

I did not need to use any regulators as the AC adapter is switched(keep this in mind when doing your purchase).

Testing to see if it works(And it did)

Basically what I purchased are these following items:

  • 5VDC 3A 15W Switched AC adapter
  • Wire cutter
  • Electric tape(soon to be replaced by a cap)

I did this will almost no electrical knowledge and read online about connecting positive and negative wires correctly.  So in effect, this tutorial is written for those with the same type of knowledge but would rather avoid searching everywhere online for the information they need.

Start by taking the AC adapter and the wire cutter, snap off the normal coaxial connector that is shipped with these units.  Be sure to buy a unit which clearly indicates which wire is positive and which is negative.  Normally the positive wire has a stripped gray line going through it.  Originally I thought the stripped line wire was for the negative, thank god I did my research before attempting to connect it to the plug...

Next, splice the wires apart on the AC adapter cord to have to wires.  Then either use a wire stripper or manually strip the wire, which I did.

After which, take your old PSU and use the wire cutter to snap off the Molex connector(the one that attaches to the Sheeva Board.  Strip all four wires to reveal the steel wires underneath.

Now, the fun part.  Twist both red wires together from the Molex connector, and also twist the black wires together to form two wires for positive and negative.  From the AC adapter, take the positive lead(one with the strips) and twist it together with the red lead from the Molex connector.  Next, take the negative lead from the AC adapter and twist it together with the black lead from the Molex connector.  Use either electrical tape, sodder, or a cap to keep the wires together.  I found that the legs from the SheevaPlug can also work as a temporary cap due to the hole in them.

Plug the AC adapter into a unpowered power bar with a on-off switch.  Switch the power bar on and enjoy a working Sheeva Plug with an external AC adapter.  I would recommend using the power bar when testing for the first time, due to the fact that if anything fails a flick of a switch can disable the power source and avoid possible danger.

The exact specs of the AC adapter used

With this AC adapter, I have tested connecting devices to it.  I copied these three photos from my phone connected to the device via USB through Ethernet by connecting via SFTP.  It even began charging my phone as well.  So, in effect, a 15 Watt AC adapter should work perfectly for any application on the device.

Happy moding!
11  Hardware and U-Boot firmware / Hardware / Re: How to power SheevaPlug with AA batteries? on: September 24, 2010, 11:54:43 PM
Thank you for your reply.  I guess the Beagle Board uses different components to make it run from a PCs USB host, hmmm.  I was looking into the AA/AAA idea as I have an Open Source Game console, the GP2X, which runs on AA batteries and lasts about 3 hrs or so. Never actually took the time to count how long it lasted.  The GP2X also runs a ARM processor and Linux, but it is clocked much lower(I set it to 200Mhz for most apps) which would explain more battery drain from the Sheeva's ARM processor.

I'll look into either a separate DC adapter or see if a local electronics parts store is able to replace the capacitor or build me a new PSU.  However, I would love it to run from some sort of battery power.  I could change it from a Plug to a handheld Linux system with the proper parts.  USB touchscreen mainly. Cheesy
12  Hardware and U-Boot firmware / Hardware / How to power SheevaPlug with AA batteries? on: September 24, 2010, 08:16:11 PM
I have read on multiple forum posts that it is possible to power the board with AA/AAA batteries.  Since my plug's power supply has died, popped capacitor unfortunately.  I opened up the casing and noticed how simple the power connector is, and how common it is.  I live in North America, and we have a store here called "The Source", which sells battery enclosures for AA/AAA for electronic projects.  I do not know much about electronics and am not sure which casing to purchase and for how many batteries it should occupy.

Are there any special considerations for connecting the cable to the J3 input?  Which terminals from the batteries should connect to which pins/colors on the J3 input?  I would rather not blow the board from connecting the batteries in the wrong way.

Also, how would one build a USB power supply for the SheevaPlug board?  I would love to use the board much like how the Beagle is used, which is powered by USB power.  I know it cannot be powered from the JTAG microUSB port, but information on how to splice a USB cable and adapt it to the SheevaBoard's J3 input socket would be great.

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