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Cap. Touch-Board

Cap. Touch-Board




->Functions of the board:

->Fitting Case:

->How to get one ?
-Contact @Cherry97 for the PCB (bulk order of PCBs and components)
-CAD-files for downloading => https://hackaday.io/project/28044-hacking-an-fairphone/files
-Case can be ordered via shapeways
-direct order of the case => http://shpws.me/Pn7H

->How to position the spacer?
-3D-printed spacer (0.7 mm):
=> If you have a printed spacer, you should position it in the way it is shown in the picture.
In this position all connectionpoints have a good contact and datatransmission is
=> By varying the position of the spacer, connection problems can be fixed easily.
=> If the board doesn´t seem to power up, check the pads on the back of your case
with a multimeter. The voltage between the left and the right pad should be about 5V.
=> To secure the spacer it´s the best to mark the working position and attach it with
doublesided tape.

-DIY spacer:
=> By stacking a few layers of tape (e.g. Capton-tape) you can replace the printed spacer.
=> The hight of this batch should be about 0.7 mm and the position of it should be the same
like the one from the printed spacer, which can be seen in the picture above.

Is everything working?
-> If the spacer is positioned correctly and you didn´t change the flashed software you should
see the “Hallo World”-sketch doing it´s thing.
=>The sketch should run fluidly.
-> Check if one of the upper LEDs is fading, this would mean the connection is not perfect (or better your board went somehow into programmingmode).
-> Check the voltage on the pads in the lower right corner of your case, the voltage between the last pad on the right and left side should be 5V (DC).
-> Upload the FP2-Basic-Sketch via ArduinoDroid, which can be downloaded for free from the PlayStore. In ArduinoDroid, set the board type by navigating to the hamburger menu (top right) -> Settings -> board type -> Arduino -> Micro.
-> Download the “FP2 Extension Control”-APP in the PlayStore (source code here) and try to open/start a serial connection. Now you can test the functions of the DIY-shield.

=> What it should look like => Hallo World (How to)

=> How to upload a sketch? => ArduinoDroid as uploader

The easiest way to update the software on your extension board is, like you see in the video, with the App “ArduinoDroid”. You don´t need any programming adapter and it is done quite fast. To bypass the needs of adding libraries to your phone it is the best to upload a precompiled sketch. You can compile your own sketch on your computer and upload the hex-file to your FP2 or you use my hex-file(s) which is available on GitHub or Hackaday. To get the upload running with your DIY-shield or any other PCB with a microcontroller attached, you have to select the right kind of µC. In the case of the DIY-shield or the cap. touch extension this would be the Aruduino Micro. If this setting isn´t working for you, you can also try to set the Arduino Leonardo. Both controllerboards from Arduino are built around the Atmega32U4.

=> Where to get a sketch? => GitHub

=> Is there a way to controll the extension ? Extension Control (APP)

=> How to use under LineageOS?
-> Flash newest image to your FP
-> restart into bootloader
-> open adb on your computer
-> insert “fastboot devices” into terminal
-> download this image
-> insert downloaded image into your “platform-tools”-folder
-> insert “fastboot flash boot FP2_boot_back_usb.img” into terminal
-> reboot FP with “fastboot reboot”

=> There are reboots when you attach a extension board (under normal FPOS)?
-> install the “special update” via the updater ( FPOS )
-> install Logcat (APP, no root needed)
-> start ADB (on your computer)
-> enable usb debugging
-> write “adb devices” into the command line
-> start the APP
-> wirte “adb tcpip 5555” into the command line
-> disconnect your FP from the computer
-> click on the reload icon in the app
-> now you can read the log of your phone

=> Still having reboots?
-> Check the level of your battery and charge it up.
-> To be sure that the DIY-shield is not causing the reboots, it’s best to take a look a the PCB and search for shorted circuits. The easiest way to do this, is by using a multimeter.
-> Solder together the RST-jumper (lower right corner of the PCB) to enable the PULLUP-circuit.
-> FairphoneOpen is working best with the extensions. It´s really worth a try !!

=> The temperature shown in the APP is not correct?
-> That is quite normal because the solder pad between the A5-pin and the voltage divider of the NTC must be soldered together, to activate this feature.
-> To disable the temperature feature just remove the tin of the connection pad, so that you can use A5 as normal analog pin.

=> How to prepare my DIY-shield for some DIY-action?
-> First cut the female pinheaders to the right length (they should not reach the other side of the pcb when attached on it ).

-> Now solder them to the board (watch out for the right vertical angle !! )

=> Keep in mind:

I`m not liable for any damage that occurs on your mobilephone!!

Be carefull in the making process and better double check resistance and connections of the PCB!!

Under normal conditions and use of the PCB there will be no problems or damage on your phone!!

Both the DIY-shield and the cap. touch extension have a build in ntc-fuse to protect your FP. It`s important to know, that the max. current you can use is 200 mA!! The LEDs on the boards draw about 10 mA each and a Neopixel at full brightness draws about 60 mA !! Keep this values in mind if you are creating your own circuits and sketches for the PCBs!!

(edited by: Cherry97)


IR-remote-addon for the DIY-shield -> WORKING <-

=> This addon adds a fully working remote function to your FP2.

=> The IR-addon in action!!

Sound and Neopixels

=> This extension for the DIY-shield adds an external microphone, which can be read out by a analog pin, and furthermore it adds 6 NEOPIXELS, to visualize sound.

OLED-addon for the DIY-shield -> WORKING <-

=> This extension for the DIY-shield adds a fully programmable/controlable OLED-display to your FP2.

=> To see the display in action, just click here.

=> The I2C-address for this addon is 0x3C, this information is very important to get a proper connection with the OLED!!

=> This addon was created by using the files of this product from the awesome company called Adafruit !!

=> Adafruit not only sells good quality products, but also teaches how to use them. To find out more just have a look at their webpage.

QuiteSomeLEDsAddon for the DIY-shield -> WORKING <-

=> If the 8 LEDs on the DIY-shield are not enough for you, this addon is the right one !! 105 LEDs are attached to this PCB. All of them are fully controlable via the I2C-interface on your DIY-shield!!

=> Furthermore this PCB includes also headerrows to add your own ideas and circuits to the addon. I used those rows for adding buttons in order to play games on this matrix.

=> You love your Fairphone? Me too !! Show your love with your own LED-matrix, just like you can see in this video.

=> I also programmed a nice little game for this addon, which is quite fun to play.

=> A precompiled and a normal version of this game are available on my hackaday-page free to download.

=> The I2C-address for this addon is 0x74, this information is very important to get a proper connection with the matrix!!

=> This addon was created by using the files of this product from the awesome company called Adafruit !!

=> Adafruit not only sells good quality products, but also teaches how to use them. To find out more just have a look at their webpage.

Atmospheric Sensors

QI-Charger (Wireless Charging)