Touch Screen Alignment/Calibration

Jul 25, 2015
<img src="/styles/default/custom/flags/gb.png" alt="United Kingdom" /> United Kingdom
TomTom Model(s)
ONE Canada 310
Hi i have tomtom one canada 310 it was working fine, but werk ago i starts have a problem with screen, when i touch right side it press left letters. How i can calibration this model ??? thanks for help
That isn't a model number, it's a licence certificate. See here to identify:

Try a drum reset on the unit by holding the power button about 20 seconds till you hear the drum sounds unless your model has a dedicated reset hole.

Also, follow the info in the following links. May assist:

Hello fellows,

I've got touchscreen issues on my TT GO 920, I know there's heaps of threads on here on this subject but being a non-native english guy, I have a hardtime understanding some of the offered solutions. So please bear withe me and try to respond in a clear way. Besides Í haven't been reading anything about a touchscreen that has lost all touchpoints on the screen, all I've been reading is people that either needed to move the touchpoint to the left or right or up or down .... my issue is a bit more complex as my screen doesn't recongnize anything at all.

To simply matters I've removed my SD card and copied both a calib and cal txt file into the root of my device that I've been altering for the last few days, with no luck at all :(. As I reckon if I get my device to work properly from it's internal drive after finding the right combination for my calib and cal txt files, I can easily copy them onto my SC card and bob's your uncle (atleast I think it should work like that)

Been reading a bunch of stuff on the net and in this forum, including the links provided by dhn about it, but haven't been able to solve my issue. The point is that my touchscreen is so far of the mark it doesn't respond anywhere...... leaving me with no refference point at all.
My calib on reboot reads: 79 934 130 858 that I've swapped into 934 79 130 858 for my calib.txt file and 934 79 858 130 for my cal.txt file as I've been reading in some other topics on this subject.

As I can't get to accept the legal stuff upon start up by touching the ACCEPT button on the right bottom of the screen, nor can I hit YES or NO to the question if I want to grant my PC access to my TT or not whilst my TT is in it's charge cradle I guess the values to change are:
MIN X => decrease the default value by 40 for starters (to move the touchpoint more to the left on the right edge of the screen)
MIN Y => decrease the default value by 40 for starters (to move the touchpoint more to the center of the screen)
So my calib.txt file will read: 934 39 130 818
and my cal.txt file will read: 934 39 858 90

Am I making any sence or not ..... ?

I've made the above changes, but with no luck, I've even gone as fas as decreasing these values by 200 without any luck so I'm kinda lost at this stage ....

Looking forward to recieving your expertise on my issue.
Cheers !
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The following post, a real blast from the past, identifies both the correct filename (cal.txt, not calib.txt) and coordinate order as you have already understood it.
Two things can go wrong:

1) Beware that your text editor isn't creating a file called cal.txt.txt due to hidden Windows file extensions.
2) Be certain that the file is true vanilla text. You don't even want a CR (0Dh) or CR/LF (0D0Ah) at the end of the line.

An adjustment can be made by placing a file called cal.txt in the root directory of your 720920. All firmware versions since 8.051 require the sequence in this order:
MaxX MinX MaxY MinY
(where X = left/right and Y = up/down)

For Left/Right calibration:

MaxX affects the LEFT edge of the screen
Increase MaxX - touch point moves to the RIGHT of where you touched
Decrease MaxX - touch point moves to the LEFT of where you touched

MinX affects the RIGHT edge of the screen
Increase MinX - touch point moves to the RIGHT of where you touched
Decrease MinX - touch point moves to the LEFT of where you touched

For the Y axis, the process is the same only in the up/down axis.
I had this same problem with my old GO 740 and had to make some adjustment to access the bottom areas of the screen. My file looks like this:

926 77 830 200

If you press and hold the reset button in the bottom of your unit briefly. Now, press and hold the power button until the screen appears with white text on black background, then you can release the button. You will see a line on the screen that looks like this:

Touchscreen calib. data: 76 932 140 861

Beware! On THAT screen, the data is MinX MaxX MinY MaxY. Don't use that order when you create your cal.txt file! Anyway, this shows you where the unit calibration is by default if there is not any cal.txt file to change it., so you use this as a starting point for your adjustment. If your screen showed the numbers above, that would the same as if you had created the cal.txt file that looked like this: 932 76 861 140

You should create the file with Notepad or another very basic text editor that will allow you to create the file as BARE text and does not require line break at the end of lines.
Thanks for your reply, it's highly appreciated, but can you elaborate on
2) Be certain that the file is true vanilla text. You don't even want a CR (0Dh) or CR/LF (0D0Ah) at the end of the line.

What do you mean by "You don't even want a CR (0Dh) or CR/LF (0D0Ah)" .... I'm using MS Notepad to create my cal.txt and calib.txt files and I've look buit wasn't able to find any program settings on it at ....

Look forward to your or anyone elses respond !
Notepad is one tool that can avoid what I was describing. What you, as a non-programmer, have probably never seen is how a text editor terminates lines so that it knows where all of the line breaks are!

Using Notepad, what you do not want to do is hit the "Enter" key at the end of the line to drop the cursor to the next line. If you do so, backspace from the line below so that the cursor comes back up to the end of the line of numbers so that there is NOTHING below it.
Understood - Cheers mate !

Now all I need is to figure out by how much I need to change the numbers to get my touchscreen back so it responds whenever I touch it because right now it doesn't respond in any sector of the screen.

For the record, I can put both a calib.txt and a cal.txt file in the root of my TT and alter the numbers at the same time right ?

Am I right when I say - please confirm:

MaxY Affects the Top edge of the screen
Increase MaxY = Touch point moves closer to the Top of the screen
Decrease MaxY = Touch point moves closer to the Centre of the screen

MinY Affects the Bottom edge of the screen
Increase MinY = Touch point moves towards the Bottom of the screen
Decrease MinY = Touch point moves towards the Centre of the screen

Could taking of the power, by disconnecting the battery pack reset my TT so the original set of cal.txt numbers in my TT's internal and non-accesiblepart of the TT's software do the trick ... I know it's a long shot but you'll never know .... beats the hell out of trying to figure what number to change and by how much to get my touchscreen back up and responding.
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No reason to do both. Only one is effective as noted.

No need to remove power. Each hard reboot ('pin reset', using the hole in the bottom) of the device is assured to read the original factory settings, and if available, the calibration file which will override the factory setting. The original factory numbers cannot be changed under any circumstances, which is why the calibration file was designed to override it.

It's a bit of a trial and error process.

If you screw the calibration file up so badly that you can no longer even hit the YES button on the face of the unit to connect to computer on power-up, you can pre-connect your device while powered off, hit the reset button in the bottom, and it will automatically connect to your PC without even asking. That lets you delete or replace a completely hosed calibration file. Ask me how I know that .....

Thanks for your reply !
Understood that taking off the power isn't going to be of any help solving my problem ....geuss I'm back to the trail and error process.
The thing is I have no clue where to start as I have no refference point at all on my screen that is responding to my stylus. In other words, I could be making adjustments to bring the touchpoint more to the left and bottom but in reality I should be making adjustments in the opposite direction.

I want to use both the cal.txt and calib.txt files as I'm not sure what Navcore there's currently on my TT GO920 T.

Cheers !
Good place to start with is to try to bring up a 'keyboard' -- for address entry, for example -- if you can get it that far. That will leave you a fair bit of real estate where pressing somewhere on the screen will return a number or letter or whatever from the 'keyboard' that will appear above, showing you where you're hitting vs. what it's seeing.

Again, there is no point in using both files. Only one is recognized by your unit's firmware. If you plug your unit in and let Home 'read' it, you can find your version number that way. Connected and with Home running, use the "Help" tab up top, then select "System Information". Scroll down to "Connected device: TomTom GO 920..." and below that in the "ttgo.bif file contents" area, look at what it says for "ApplicationVersionVersionNumber=" Toss a decimal in after the first digit (8 or 9) and you have your firmware version.

For example, my 740 reads as follows
which indicates I'm running firmware version 9.510

Cheers for you input mate, I really appreciate it !
Turns out I'm running ApplicationVersionVersionNumber=9510 so like you I'm running Navcore 9.510
Knowing my Navcore version is above 8 I can rest asure cal.txt is the only file I need ..... now all I need to do is figure out what the values need to set to for the touchscreen to get in working order.
I'm going to try and hook my TT up to my PC as described by you earlier in this post as I have no way of getting anywhere near to the TT's keyboard.
pre-connect your device while powered off, hit the reset button in the bottom, and it will automatically connect to your PC without even asking. That lets you delete or replace a completely hosed calibration file

.... to be continued

I got it to connect, but actually I didn't need to use the above method as I can access the internal drive when I hook up my TT to my PC .... I was hoping to get to the keyboard on my TT but I couldn't.
I can use the TT thru my PC but it doens't show any map or keyboard on my TT while I do it.

I managed to get some progress .... I had to select a map and it worked, but it seems in terms of hight my TT is about 10mm off center (meaning that the point that is selected is about 10mm higher as where I touched the screen) ....
Is it possible to say approx. by how much I would need to Decrease MaxY to move the touchpoint about 10mm down or is there no similarity in that aswell, meaning decreasing MaxY by let's say 50 on the cal.txt file on my TT could be what's needed to move it 10mm down but on someone elses TT it might be only 25 or something like that?
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