RISC OS, raspbery pi & lapdock query

With the raspberry pi having been shown to work on a Motorola lapdock I went ahead and purchased one. With RISC OS on the SD card and the necessary connections the pi boots up and displays the desktop. Only problem is that the keyboard and touch pad don’t respond. After a short time the screen saver kicks and boy oh boy does the swarm fly!

Can anyone who has successfully joined the two let me into the secret of how to get the keyboard and touch pad active please? :-)

How have you connected the keyboard and touchpad? On mine, I used a Blackberry split charger cable, like this one and took one part directly to the microUSB power-in part of the Pi. The other one I split to cut the red (power) cable and used a microUSB-USB adaptor, like this one and plugged it into the Pi’s USB port. This also enables the two USB ports on the LapDock. There is a picture of my wiring here but it’s not that helpful.

I need to point out that the LIKE this one bits may be relevant! My splitting cable is a BlackBerry original, and the MicroUSB to USB adaptor looks a LOT better made than the one I’ve linked to. I can’t remember where I bought them, but not from the places I’ve shown. They were the first ones I could find in Google Images!

I’ve had a Lapdock for a while and it works well with RiscOS on the RPi. Only issue that I get is occasional ‘stuck-down’ keys on the Lapdockkkkkkkkkkkkkkkkkkkkk. Note that this is probably an issue with the RPi USB drivers or voltage levels and not an issue with the Lapdock AFAIK. Not tried the Lapdock on my newer 512Mbyte Welsh-built RPis – these should be better as the RPi Pico fuses have been eliminated from the newer design.

Most issues with the Lapdock are due to a low 5volt rail on the RPi (i.e. an inadequate power supply or voltage drop due to the older RPis pico fuses etc).

Q. How are you powering your RPi (If from Lapdock via which RPi socket?) ?

Q. How have you cabled up the RPi to the Lapdock (there are several options) ?

Q. Do external USB devices work OK on the RPi in the Lapdocks own USB sockets (these should work) ?

Q. What revision of RPi do you have ?

Q. What RiscOS build version are you using ?

Make sure that your USB data cable for the RPi→Lapdock has the data wires included (some cables have just power).

Have a search of this forum, and also the main RPi forum for more information on the Lapdock/RPi.

Also Google is your friend…

Ralph

I have try this

RPi

and

BBxM

with this

prototype

Any question? ;-)

Sorry, I was in my car on the road with no traffic (means traffic jam) ;-)

Power: No problems with powering from Lapdock USB micro to RPi USB Host.
Also no problems from Lapdock USB to RPi USB micro and a additional Cable from Lapdock USB micro to USB Host.
All cable self made.
For HDMI I use a MicroHDMI(f)toHDMI(m)adapter.

I have a 16GB MiniUSBStick in the 2. RPi Host and my UMTSStick in the Lapdock USB. No problems.
I also habe try a HD…

I have a “old” 256MB and a new 512MB one. Both works fine.

I use the last Distro with NutPi and a December ROM.

Too many I’s ;-)

I don’t think you need to blame the lap dock; I have a 512 Pi that has the same keyboard issue whether the kbd is connected via the onboard sockets or the hub in my NewerTechnology miniStack hacked-up case. It doesn’t happen often but it somehow knows when the worst time is.

Sorry I don’t understand your post. My english is to bad and google translate confused me.

My Lapdock etc. works fine.
If there are misunderstandings occurred, sorry.

Thanks Andy, Tim, Raik and Ralph for your advice.
The pi is the latest version (Chinese made from e14)
RISC OS Pi from ROOL – latest distro on their SD card
used adapters for both HDMI and micro USB on lapdock port
USB cable from one of the lapdocks USB port to pi USB port

I will persist with various combinations once the battery recharges. Although the pi power was cut when lid of lapdock closed the USB port must have continued to draw power as the battery is showing less than full – a lot less!

Thanks to your contributions I have a number of avenues to pursue knowing that the keyboard should indeed operate. I’ll switch cables around as I have a few different types.
:)

The “problem” is that
First: The micro USB port on the Lapdock retains its power (to load the Atrix in original). The RPi is also powered on (the LED is on).
Second: The RPi can be powered from the USB host (the BeagleBoard not).

I did some experiments, and stayed in the variant micro switch in USB connector. I just turn off +5 V. I think the same make CJE with her “light switch”.
Another variant is the 3-cable solution.
HDMI as usual. A cable without +5 V from the Lapdock micro USB to the RPi USB host and a smartphone charger cable from Lapdock USB to the RPi micro USB.
USB connectors of Lapdock be turned off when the lid is closed.

<I will persist with various combinations once the battery recharges. Although the pi power was cut when lid of lapdock closed the USB port must have continued to draw power as the battery is showing less than full – a lot less!>

When the Lapdock lid is closed the power on the USB/HDMI? ports is only momentarily cut for about a second, then the power comes on again with the Lapdock lid in the closed position. This is unfortunate for RPi users, although this is the way the Lapdock was designed to work by Motorola. There is lots of discussion of various hacks for changing this on the ’net (mostly on non-RiscOS forums).

Ralph

This is what I have described above. According to Motorola, this function is hardwired. Therefore, there are the various switch versions (see my pictures above).

A lapdock does interesting things with power when you close and open it!
As Ralph says: As you close the lid it cuts power off to the USB socket momentarily and the turns it back on, whilst closed.
When you reopen it does the same again (cuts power off to the USB socket momentarily and the turns it back on.)
The loss of power is enough to cause the Pi to restart.
Using a MK2 and our special power cable using USB A we connected a £15 USB battery to the Pi’s microUSB port it was able to stop the Pi from reseting when closing or reopening a lapdock.
However adding a nano router powered via the Pi’s USB port added enough to the power load, that the USB Battery couldn’t stop the shutdown/restart!

Raik: I like your handy work. Very neat solution – wish I was as confident as you ;-) Your comments have been very helpful.

Chris: Thanks for taking the time to give a detailed explanation of what is happening. The in line power switch you offer looks great.

Thank you. I had many opportunities to practice;-)
With the right tool is not difficult. The new cable has a smaller switch.

I found a neater solution to the USB cable/connectors on ebay it has a micro female USB to go on the lapdock and the other end is a male micro USB to go into the RPi – it is a right angle.

ebay
Micro USB 5 Pin female to down angle 90 degree Micro 5P male plug Cable adapter – from dailyappliance2010

The cable is also short at around 10" so should be suited to the lapdock/pi combination with a little paring and sandpapering to get the female plug to sit alongside the HDMI coupler.

Not sure if you fixed the initial problem. I experienced exactly the same problem and it turned out to be a problem with my micro usb cable, it was power only, not data.

Ross: That cable would connect up power from a LapDock to the Pi’s microUSB power input, but that socket on the Pi is only for power the USB lines are not connected.
mk1 Pies are awkward to connected to a LapDock
Mk 2 are easy if you use our special switched USB & Power cable http://www.cjemicros.co.uk/micros/individual/newprodpages/prodinfo.php?prodcode=4D-RPI-ATRIX-PI-USB-SW
And for HDMI : http://www.cjemicros.co.uk/micros/individual/newprodpages/prodinfo.php?prodcode=4D-RPI-ATRIX-PI-HDMI
These give what I think is the neatest solution as shown here: http://www.cjemicros.co.uk/micros/products/lapi.shtml
Since taking the photo’s we have shortened the USB cable so it is even neater. The HDMI cable might look too long but when the Lapdock is closed it needs almost of that length. We’ve velcroed the Pi in place!

By shuffling the cables and trying different combinations as suggested above I’ve got it working correctly. Have ordered a number of the switched USB power cables from Chris to tidy up the whole setup.

Next task is to install software to enable the touch pad to provide a ‘menu’ button function.

Thanks to everyone for their time and contribution to help me resolve the matter.

At the South West show I brought along my minimalist Rasperry Pip for the Lapdock. Several people showed an interest, so I have posted some pictures at:

It is not an adaptation for the faint hearted, but is quite neat.

i got the same prob on my lapdock:
first it worked, but after the 3rd time pluging in the adaptors for the pi, the keyboard/pad / hub didn’t work anymore.
was a hardware-defect of the lapdock, had to unmount the covers, and to remove the micro-usb-socket.
Had a bad soldering-point (cable broken). not repairable, therefore i soldered a complete new cable.

At the South West show I brought along my minimalist Rasperry Pip for the Lapdock.

Steve, which adapters and enclosure did you use? I’m interested in doing something similar with my Lapdock 100 and an original model B.

@Steve Drain

Yours looks like mine ;-)

SchlepPi

Yours looks like mine ;-)

But chunkier. ;-)

A nice piece of work, but you will have to get out the desoldering tools.

It is a shame that there is little prospect of the Pi being available from the production line before the hand fitted components are soldered in.

;-)

I have nothing desoldered because I use original Tekberry box with the Model A and I use a afruit realtime clock (not on the pictures) and a small afruit SD to microSD adapter.

@Raik

Your SchlepPi uses the AdaFruit clock module. I have used the CJEMicros unit. It is more expensive, but I know it works out of the box. Does yours?