Calibrating a 5″ Raspberry Pi touchscreen in Jessie

Previously, I posted about a 5″ touchscreen for the Raspberry Pi.

But I did not mention calibrating the touchscreen.

After a week’s holiday, I came back and sorted this fairly easily.

I was using Raspbian Jessie from NOOBS 1.8

First I installed a new utility:

sudo apt-get install xinput-calibrator


To calibrate the touchscreen, go to the menu>preferences>select “Calibrate touchscreen”

Touch each of the red crosses on the screen in turn, then cut and paste the resulting snippet to the following file by using this command:

sudo nano /usr/share/X11/xorg.conf.d/98-calibration.conf

(this will create a new file and open it for editing)

My entries are below:

Section “InputClass”

Identifier “calibration”

MatchProduct “ADS7846 Touchscreen”

Option “Calibration” “120 3970 205 3920” #(enter your numbers here)

Option “SwapAxes” “0”


Ctrl-O to save, Crtl-x to exit, and then reboot, and your pointer should follow your finger correctly!


Orange Pi One

This is just a quick and dirty guide to getting the Orange Pi One up and running.

First steps:

  1. DON’T connect a microUSB charger to the MicroUSB port. That port is for USB On the go only, i.e. for connecting flash drives etc.
  2. You will need a 5V power supply with a 4mm x 1.7mm barrel connector, centre positive. I used a USB to barrel connector lead, and a Samsung USB charger, which can easily supply 2A. Apparently PSP chargers work as well.
  3. You will need an SDcard for the OS. At least 8GB and preferably at least class 4. A fast one is recommended, apparently the Opi1 may not boot with a slower one.
  4. EDITED:I have since found that some class 10 cards will not work with the OPi1 or even the Raspberry Pi. I used class 4 Kingston 8GB cards, and they work perfectly with both.
  5. If you power on the OPi1 without a properly set up SDcard, nothing will happen, except that the LEDs on the Ethernet port will light. THIS IS NORMAL.
  6. Prepare the SDcard. I followed this excellent guide:
  7. Once connected up with a valid Boot image, the Ethernet port LEDs light up, followed after a pause of about 20 seconds by the red LED and then the green one will flicker as the system loads. (note on some boards the green LED lights first)
  8. Note: I noticed that if the Ethernet port is not connected, it takes a lot longer to start up.

I have added a Youtube video showing a working Orange Pi One  (and a faulty one)

Sugar free…..No, Really Sugar free.

A recent diagnosis of Type 2 Diabetes has caused me to take stock.

So no more snacking, no more high sugar recipes, Healthier alternatives..

I was quite interested when I saw The Great British Bake Off listing a sugar free  round, then I watched it and was horrified.

Nobody came up with a sugar free recipe.

They all used sugar substitutes, such as  Agave Nectar, Molasses or Honey.

Now, Honey may have trace elements and add flavour, but at the end of the day, it is still a sugar syrup.

Agave nectar is a highly processed product loaded with Fructose (even higher than HFCS), which is arguably worse for you than granulated sugar.

Let’s be honest people, recipes using Honey, Agave Nectar or Molasses aren’t “sugar free”.

I suppose that you could call them “healthier sugar”, although even that label is debatable.

Although they are sweeter than table sugar, so you might be able to use less, they are still sugar.

They are certainly not good for diabetics.

So, I am going to investigate sugar alternatives.

Back from the the brink…

Sometimes the easiest things become difficult.
I decided to swap the monitor on my living room PC.
The new monitor is physically the same size, despite having a slightly larger (23″ as opposed to 22″) visible screen. It also has a higher resolution, 1920×1080 instead of 1640×1050. So I thought it would fit nicely in the bookcase where the current Samsung was.
First problem: no VESA mount, so needs the stand.
Had to move one of the shelves.
Homemade bookcase, screwed together, but not too much of a problem.
Half an hour later, boot up, on HDMI lead. no picture.
Close down, boot on vga ok.
Reboot, oops, caught power lead, pc switched off, Boot up, kernel panic.
After a short google, downloaded and tried Rescatux recovery CD.
Brilliant package! PC working again.
Now just have to figure out why monitor not working with HDMI>DVI lead.(sigh)

Sometimes even spectacles can’t help us see more clearly

Last night, my mouse left-click stopped working.
Cursed, changed batteries (wireless mouse) no good.
Tried another wireless mouse, batteries were dead, no spares arghh!
Shutdown (Ctrl-alt -F2, it’s a Linux box) and went to bed.
This morning, dug out spare USB mouse from parts bin, booted up- no left click!

Then I noticed that my spare (metal framed) glasses were sitting on my Wacom tablet, which uses a magnetic field to detect the pen- Doh!

Upgrading the Acer Aspire one

Well, my Acer is no longer in warranty, and although its great, it is a little slow updating web pages, etc.
So I decided to upgrade it to a 16GB SSD read/write 40/80, add an extra 1Gb of memory, and swap the wifi card for an 11n one.
Followed tnkgrl’s excellent video, and all went smoothly. Now web pages load instantly, and I can stream video in real time from my mythTV box:)

Windows 7 and the lost 4 hours

The previous post was written when 7 first arrived.
However, we have recently been forced by an XP update trashing 2 HP PCs, to “upgrade” them to Vista, so that the network cards would work!
These 2 PCs came with a “free” (cost £21 each) upgrade voucher for 7, so decided to test 7.


I have a nice, if rather heavy, Dell laptop, it came with XP, and I have installed OpenSuse 11.2 on it.
all works, but decided to bite the bullet and install 7.
The initial install went OK, used all the 200GB free space on my disk, but I can change that later…
Of course my OpenSuse distro was unreachable, so popped the OpenSuse disc in and recreated the boot manager.
all ok, then decided to install Office 2007.

All went well, up until the blue-screen that is.
After Office 2007 had crashed my PC, Windows7 tried to repair it and my OpenSuse install disappeared. Tried to reinstall Office, no go. after various attempts, safe mode logins, etc. and following instructions from various Microsoft help links, gave up and wiped 7 and started again.
This time, the mouse stopped working half way through the install…ho hum, wipe and try again.
So far, this time it seems to be working, but I still haven’t got an OpenSuse boot option.

Now I know how Linux newbies feel….

Update:windows XP no longer boots either…..

Windows 7

Well, Our Microsoft Action Pack disks for Windows 7 arrived today.
Installing as an upgrade to a largely unused Vista Ultimate install. (only used for testing media centre)
Was a little nonplussed when it said “upgrading your installation may take several Hours”!
As it happened, it did take nearly 3.
First it insisted on updating Vista, which as it hadn’t been used for a couple of months, took a fair while.
Then after all the file copying and compulsory reboots, it launched.

Quite impressed by the user experience, quite unimpressed by the fact that every management task seems to need at least one more click, or strange manoeuvres to reveal the hidden tools.

Everything seems to work OK.
The media centre is pants though.

How much can we simplify Linux?

I just had a “First steps with Linux” article printed in a popular UK computer Magazine.

It was designed to tell  the new user what to do after they had successfully installed UBuntu.

The Distro was chosen as being the most mainstream, and I thought that too many articles on Linux drop the user after installation.

Most of the feedback on the Magazine’s forum was positive and complimetary.

Except one.

The post in question was a request for a “total idiots guide to Linux”.

Well  I thought that was what I had provided.

The poster went on to mention unfamiliar terms like “distro” and “grub” (both of which were explained in the text), followed by a

complaint about “typing symbols” and “Where should they be typed”

(again this was explained in the text)

The CLI “taster” section was less than half a page of an 8 page, 6000 word  article.

I did hesitate to include  it, but felt that it was necessary for completeness.

The poster must have skimmed the article without reading it, and picked anything that he did not instantly recognise as a problem, and then complained.

I suppose for users like that, the best advice with regard to Linux is “forget it, unless you can get someone else to set it up for you.”

I have several Linux users who would have no idea about installing or maintaining Linux, who happily use it on a daily basis, with no problems.

All the real complaints come when windows users try to install it themselves.

KDE4- the revelation

Well, after a long time as a KDE3 user, I was staring into the barrel of a warm gun.
Opensuse 11.2- KDE4.
I had to decide, move to KDE4, become (shudder) a Gnome user, or move to my best alternative- XFCE.
I had tried KDE4 in earlier incarnations, stability and usability issues stopped me experimenting further.
I finally bit the bullet and installed in a VM to test.
At first it was confusing, but once I threw away all convention and read the manual, it worked well.
After a short period of acclimatisation, it just works so well for me, I am astounded by the logicality of it all!
I have played with various GUIs, and this is a real revelation.
Not the half hearted redraw of Vista or win7, but a new, well thought out approach.

As for Opensuse, my dual monitors were identified and configured, along with my Wacom Bamboo tablet, I now have seperate Xserver settings for each login, and it just works smoothly, including interfacing to Exchange on the laptop.

Yes, it is still in development and there is the odd rough spot, but overall, a real advance in usability.
It now sits happily on my main desktop and my dual boot Work Laptop.

Bravo KDE team, and plaudits for the OpenSuse team too!