8-Touch

under construction as of 28.9.17

Having four shutter to control but only one switch field - an eight touch pad field can help.

Using a Microchip CAP1188 (easiest to purchasee a complete module from Adafruit) can solve the problem. This stand-alone chip drives also 8 LED-channels which allow to give an immediate optical feedback.

Implementation

I've made a PCB which fits exactly fit into a blind cover of Jung LS990 series. LED are giving an immediate feedback once a "key" is pressed and evaluation of the touch sequence allows individual reaction

Feedback with red LED is clearly visible even under the white plastic - however only in older plastic lots. For the new one Jung seems they have changed the material slightly, so light can't shine through. Therefore I've drilled holes and cut circles out of plexi glas 40% transparence to fit in the hole. The LED underneath can then be cleary seen. In addition, I've used printable clear stickers and added pictograms for different rooms.

This is done by simple three instruction sent during initialization

  ' allow multiple touches

  call writeRegisterOneByte( AdresseCAP , CAP1188_MTBLK , 0)

  ' Have LEDs follow touches

  call writeRegisterOneByte(AdresseCAP , CAP1188_LEDLINK , &HFF)

  ' speed up a bit

  call writeRegisterOneByte(AdresseCAP , CAP1188_STANDBYCFG , &H30)

that's it!

Features

• self calibration

Ressources

• CAP1188 Datasheet
• Adafruit CAP1188 module description