First Steps with Resistive Touch Display 7" Parallel

Applicable for

Colibri iMX6ULL | Resistive Touch Display 7" Parallel

BSP Layers / Reference Images for Yocto (Linux) | TorizonCore (Linux) | wec2013 | wec7

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Introduction
Getting Started
1. What I need to order
2. Where do I order
Cable Connection
Installation on Embedded Linux
Installation on WinCE

Article updated at 27 May 2022

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Introduction

This article provides information on how to start working on the parallel resistive touch display, which includes how to set up the hardware (wiring) and install the necessary drivers for a touch demo.

Getting Started

What I need to order

The Resistive Touch Display 7" Parallel can be ordered with many Toradex computer on modules and carrier boards. See the compatible products.

Where do I order

All the products can be ordered online in the Toradex Webshop.

Cable Connection

When connecting the display to any of our carrier boards, make sure that pin 1 of the display is connected to pin 1 of the board. Due to the nature of the FFC connectors, it is possible to invert the pinout and possibly damage the display and/or carrier board.

The connectors available on the display do have contacts on top and bottom side.
Our Iris & Viola Carrier Boards also has contacts on top and bottom side of the FFC connector.
The FFC connectors on the Colibri Evaluation Board, Ixora carrier board & Apalis Evaluation Board has only contacts on the side towards the board edge.

Also, be careful with the brown levers on the connectors. They are very delicate and can easily break.
Please have a look at the pictures below which show how to connect the display with our carrier boards & Evaluation boards:

Colibri Evaluation Board Iris Carrier Board

Viola Carrier Board Aster Carrier Board

Apalis Evaluation Board Ixora Carrier Board

Installation on Embedded Linux

TorizonCore 5

On TorizonCore 5, Toradex deploys pre-compiled and ready-to-use device tree overlays for this display, inherited from the BSP layers. Enabling them for evaluation can be done with few commands. Learn how to do it on Setting up Displays with Torizon.

Reference Images for Yocto Project 5

On BSP 5, Toradex deploys pre-compiled and ready-to-use device tree overlays for this display. This enables you to evaluate it with few commands and very fast. Learn how to do it on Device Tree Overlays (Linux).

BSP 2.8 - Ångström

To configure the correct display resolution, stop U-Boot by pressing any key while booting and set the vidargs environment variable according to your module as described below. For more information refer to the Display Output, Resolution and Timings article.

Colibri VF50/VF61

setenv fdt_fixup 'fdt addr ${fdt_addr_r} && fdt resize && ${fdt_resolution} && ${fdt_touch}'
setenv fdt_resolution 'fdt set /panel compatible "logic,lt161010-2nhc"'
saveenv

Colibri iMX6

setenv vidargs 'video=mxcfb0:dev=lcd,FusionF07A,if=RGB666 video=mxcfb1:off fbmem=8'
saveenv

Colibri iMX6ULL/iMX7

setenv vidargs 'video=mxsfb:800x480M-16@60,pixclockpol=1'
saveenv

Colibri iMX8X

Unfortunately, Colibri iMX8X does not support vidargs changes, and the configuration should be changed directly in the device tree.

You can see an example with compatible changes here: Device Tree Customization Examples.

Apalis/Colibri T20/T30

setenv vidargs 'video=tegrafb0:pixclockpol:0,800x480-16@60'
saveenv

Apalis iMX6

setenv vidargs 'video=mxcfb0:dev=lcd,FusionF07A,if=RGB24 video=mxcfb1:off video=mxcfb2:off video=mxcfb3:off fbmem=32M'
saveenv

Apalis TK1

The Apalis TK1 does not provide the RGB interface required for the screen to work.

For more advanced use cases, please refer to the article Display Output, Resolution and Timings (Linux).

Adjusting the Brightness

Read the dedicated article Backlight (Linux).

Touch Screen

Resistive touch screen works out-of-the-box in our BSP. To learn more about resistive touch, read the article Resistive Touch Screen (Linux).

Touch Screen Calibration

Read the dedicated articles:

Touch Screen Calibration (Linux): if you plan to use our BSP Layers and Reference Images for Yocto Project
Touch Screen Calibration (Torizon): if you plan to use Torizon.

Installation on WinCE

Resolution

Download the CAB installer according to the OS you are using:
1. CAB installer for WinCE6 & WEC2007
2. CAB installer for WEC2013
Connect the display with the provided FFC cable to the Carrier Board or Evaluation Board paying attention to the pin numbering on the display and on the carrier board.
Copy the downloaded CAB installer to the Flash memory of the module or any of the memory device connected to the module like SD Card, USB Memory Stick, CF Card etc.
Run the installer by double clicking on it. If you do not have a working display, use the Remote Display tool.
Click "OK" on the popup window.
Adjust the splash screen settings. This is particularly important for newer displays because they need proper resolution and timings at boot. You can find more information about this here.

You can even set the proper resolution and timing parameters of RGB display through registry settings:

Don't forget to save the registry after editing.
For more information about these registry keys see: Display Driver Registry Settings

Brightness

If you connect the display with our standard Carrier boards you may experience that the display does not show to maximum brightness. To get the maximum brightness you need to set the back-light PWM_A signal to output 0.

Module	Signal Name	SODIMM Pin/MXM pin	GPIO Pin	Display Pin
Colibri PXA270	PWM_A	59	12	6(LEDCTRL)
Colibri PXA300	PWM_A	59	20	6(LEDCTRL)
Colibri PXA310	PWM_A	59	20	6(LEDCTRL)
Colibri PXA320	PWM_A	59	14	6(LEDCTRL)
Colibri T20	PWM_A	59	B4 Note1	6 (LEDCTRL)
Colibri T30	PWM_A	59	B4 Note1	6 (LEDCTRL)
Colibri VF50	PWM_A	59	PTC7	6 (LEDCTRL)
Colibri VF61	PWM_A	59	PTC7	6 (LEDCTRL)

Note1: SODIMM pin 59 on Colibri T20 and T30 has two CPU signals assigned (multiplexed) L5 and B4. Make sure you set B4 to output 0 and L5 to input.

Whereas, for Apalis T30 on a standard Apalis carrier board use GPIO C.00.

Module	Signal Name	MXM Pin	GPIO Pin	Display Pin
Apalis T30	BKL1_PWM	239	C.00	6 (LEDCTRL)

For a test you can use the GPIOConfig Tool.

For the translation of alphanumeric GPIO identifiers to numeric ones see: GPIO Alphanumeric to GPIO Numeric Assignment

Touch Screen Calibration on Win CE

The parallel RGB display also features resistive touch screen interface on the same FFC.

To calibrate the touchscreen see: Touch Screen Calibration .

To make the calibration permanent, you need to save the registry.

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