UsingMaxTouch

---

Introduction

The maXTouch Series features a complete portfolio of high-performance single-chip controllers designed to address every touchscreen size and application.

This page introduces software configuration and test tools for maXTouch. Also it contains general hardware concepts.

Software drivers and tools

Drivers

At github, under Linux4SAM

The driver for Atmel mxTouch on Linux4SAM is aligned with the driver on maxtouch in github. Now we aligned on tag maxtouch-v3.0-20140316.

When the Linux kernel boot up, if probe the Atmel mxTouch successfully, it will present similar log information as following.
Take TM7000 on SAMA5D4EK board as an example:

... ...
atmel_mxt_ts 0-004c: Must have reset GPIO to use regulator support
atmel_mxt_ts 0-004c: Family: 161 Variant: 11 Firmware V2.2.AA Objects: 24
atmel_mxt_ts 0-004c: Enabling RETRIGEN workaround
input: Atmel maXTouch Touchscreen as /devices/ahb.0/apb.1/f8014000.i2c/i2c-0/0-004c/input/input1
... ...

At github, under atmel-mxtouch

For the latest driver code for Atmel mxTouch device, you can find it on github atmel-mxtouch/linux.

Obp Tools

Introduction

Obp tools will provide an application named mxt-app, which is a utility for managing Atmel maXTouch touch controllers and other devices that support Atmel Object Based Protocol.
For more information, please reference obp-utils on github.

Build the Obp Tools

$ git clone git://github.com/atmel-maxtouch/obp-utils.git
$ cd obp-utils
$ ./autogen.sh --host=arm-none-linux-gnueabi
$ make

Usage of Obp Tools

The following is the function of the mxt-app can support.

$ ./mxt-app -h
atmel_mxt_ts 0-004c: Enabled message output
Command line tool for Atmel maXTouch chips version: 1.16-12-gdc87

Select one of the options:

Enter L:   (L)oad config file
Enter S:   (S)ave config file
Enter I:   Read (I)nfo block
Enter D:   Rea(D) individual object config
Enter W:   (W)rite individual object
Enter T:   Run sel(T)-test
Enter F:   (F)lash firmware to chip
Enter B:   (B)ackup the config data to NVM
Enter R:   (R)eset the maxtouch device
Enter C:   (C)alibrate the maxtouch device
Enter M:   Display raw (M)essages
Enter U:   D(U)mp Diagnostic data
Enter Q:   (Q)uit the application

Dump current configuration into a file.

The following command will save the configuration data in Atmel maXTouch device to a file.

$ ./mxt-app --save <configuration_file_name>

Load a configuration from a file.

Warning: "Load a configuration from a file" is highly not recommended

The following command will load the configuration data into Atmel maXTouch device from a file.

$ ./mxt-app --load <configuration_file_name>

TM7000's interface to CPU

The following is the block diagram of TM7000:

• LCD interface, from host CPU to LCD display module.
• TWI interface, from host CPU to touch key board (QT1070) and mXT768E.
  • Both mXT768E and QT1070 are TWI slave of host CPU.
  • Board designers have the chance to connect them into separate or single TWI bus.
  • Please make sure all the TWI slaves on a TWI bus are completely separated by their address.
    • This is especially important when on the TWI bus of mXT768E, as we will have all the touch coordinates on the bus.

Warning: if mXT768E is on the same TWI bus with ACT8865, we need to disabled ACT8865 after boot, to avoid wrong reaction of data from mXT768E. Check ACT8865 datasheet errata section for more details.