Getting a touchscreen to work

NETMF & Gadgeteer
1

Hi all,

i have got a board which holds an EMX. This board is developed by a supplier of us and is going to be a remote control for a device. Bassicly it is nothing more then a 7" tft with a touchscreen and the EMX.

The lcd works fine, no problems with that. Just had to make the correct setting in the emx. But the touchscreen i can’t get to work. I have contacted the supplier and they said it is connected to the emx in the following way :

X1 – Pin 4 connector – IO 5 emx – pulldown 10 K
Y1 – Pin 3 connector – IO 6 emx – pulldown 10 K
X2 – Pin 2 connector – IO 7 emx
Y2 – Pin 1 connector – IO 8 emx

We run .net micro framework 4.1. I have tried a lot of sample programs and can’t seem to get it to work… So i wonder if the connections to the emx are correct and if i have to do some extra settings in the emx.

Regards,

Per

2

Take a look at cobra schematics. I think you have the pins wrong

3

Hi Gus,

yes if i look at that schematic then the pins are wrong. I have contacted the manufacturer and that designed this pcb based on their dev. kit from GHI. But that has got the embedded master on it and not the emx :frowning:

4

EM and EMX are 99% the same but with some differences. They should have looked at this http://www.ghielectronics.com/downloads/EMX/EM%20vs%20EMX.pdf

We moved the pins so you gain 2 more analog inputs

5

Are you sure you set the correct LCD settings? Are you sure it is calibrated?
Run the calibration example in NETMF SDK.

6

Hi Mike,

well i got the touchscreen working now :slight_smile: i did this by changing the pin connections on a second board. Worked like great. So they should have looked at the pin out schematic yes.

BUT… with this screen the settings weren’t set yet. So i took the datasheet and used :

            
Configuration.LCD.Configurations lcdConfig = new Configuration.LCD.Configurations();

            lcdConfig.Width = 800;
            lcdConfig.Height = 480;

            // Only use if needed, see documentation.
            lcdConfig.PriorityEnable = false;

            lcdConfig.OutputEnableIsFixed = true;
            lcdConfig.OutputEnablePolarity = true;

            lcdConfig.HorizontalSyncPolarity = false;
            lcdConfig.VerticalSyncPolarity = false;
            lcdConfig.PixelPolarity = true;

            lcdConfig.HorizontalSyncPulseWidth = 48;
            lcdConfig.HorizontalBackPorch = 40;
            lcdConfig.HorizontalFrontPorch = 40;
            lcdConfig.VerticalSyncPulseWidth = 3;
            lcdConfig.VerticalBackPorch = 29;
            lcdConfig.VerticalFrontPorch = 16;

            lcdConfig.PixelClockDivider = 8;

            // Set config
            Configuration.LCD.Set(lcdConfig);

Screen show images etc, but i have got an offset on the x and y… I am a bit confused what i did wrong. I can’t attach the pdf file, but the datasheet is :

[url]http://www.eigergraphics.com/Download/DisplaySpezifikationen/URT_7Zoll_WVGA_UMSH-8272MD-1T.pdf[/url]

Regards,

Per

7

Ok i have got another board from the pcb manufacturer. On this one the lcd is ok (touchscreen not, but that is solved already). On my other board the screen works fine, but there is a margin on the left and top. I tried almost anything and did everything according to the specs in the datasheet.

Now my question. Is it possible to read the configuration.lcd.configurations? Or can i only set it and not read it back? Because i then would be able to get the config settings from the board that is ok.

Regards,

Per

8

I do not think you can read the config