ESP32 TouchDown

Where to buy?

Available from:

Tindie: -> https://www.tindie.com/products/dustinwattsnl/esp32-touchdown/ (Ships from The Netherlands)
Eplop Electornics -> https://store.eplop.co.uk/product/esp32touchdown/ (Ships from the UK)
PCBWay -> https://www.pcbway.com/project/gifts_detail/ESP32_TouchDown.html (Ships from China)

While working on FreeTouchDeck, I really wanted to use capacitive touch. Unfortunately, most modules I could find were resistive touch and capacitive touch has a much nicer user experience. While I was designing, it made sense to put the ESP32 on the board itself, removing the need for an ESP32 Dev board. I wanted to take full advantage of the ESP32 wireless capabilities (Wifi, BLE) so I included a battery management circuit. ESP32 TouchDown can run off of a LiPo battery and also charge it. Here is a full list of the features:

ESP32-WROOM-32D
ILI9488 480*320 TFT screen in 4-wire SPI mode
FT62x6 Capacitive Touch Controller
APK2112 3.3V regulator (On V1.1 of the board an AP7365 is used, see changelog.txt)
MCP73831 battery management IC (On V1.1 of the board a Shouding SD8016 is used, see changelog.txt)
CP2102 USB-to-UART bridge
USB-C connector
microSD card holder
Battery voltage divider connected to GPIO35
Passive buzzer connected to GPIO26
12 unused GPIO's broken out
Stemma / JST-PH I2C connector

ESP32 TouchDown works out of the box (as ESP32 Dev Module) with the Arduino IDE, providing you have installed the ESP32 Arduino Core. If you have not, this is where you can find it: https://github.com/espressif/arduino-esp32.

Documentation:

Documentation can be found in the Wiki.

TFT screen and touch controller

ESP32 TouchDown uses an 480x320 screen with an ILI9488 (datasheet) driver. There are numerous drivers out there, but I found TFT_eSPI by Bodmer the most versatile. https://github.com/Bodmer/TFT_eSPI.

Pins used by the TFT screen are:

GPIO2 -> DC_RS
GPIO4 -> TFT_RESET
GPIO15 -> TFT_CS
GPIO18 -> SPI Clock
GPIO23 -> SDI (MOSI)

The TFT backlight anode (positive supply) is selectable via a jumper on the back. You can either power it directly from 3.3V or use GPIO32. By default, the positive source is GPIO32. You can this pin and use PWM to control the backlight brightness.

Note: On V1.1 of the board the jumpers used are with bridged pads. So by default have no solder blob. See changelog.txt

The touch controller is a FocalTech FT62x6 (datasheet). The first batch uses an FT6236 and the second batch of boards has the FT6206. Both have the same I2C address of 0X38. I made an Arduino IDE library available here: https://github.com/DustinWatts/FT6236. This library also supports the FT6202.

Pins used by the FT62x6 are:

GPIO21 -> I2C data
GPIO22 -> I2C clock
GPIO27 -> IRQ

GPIO Breakout

The following GPIO's are broken out on the header:

GPIO 12
GPIO 13
GPIO 14
GPIO 16
GPIO 17
SCK (GPIO 18, used as SPI clock)
SDO (GPIO 19, used as SPI MOSI)
SDA (GPIO 21, used as I2C data)
SCL (GPIO 22, used as I2C clock)
SDI (GPIO 23, used as SPI MISO)
GPIO 33
GPIO 34 (note: INPUT only!)

SD Card

The following pins are used by the SD card holder:

GPIO 25 --> CD/DAT3
GPIO 23 --> CMD
GPIO 18 --> CLK
GPIO 19 --> DAT0

CD (card detect) DAT1 and DAT2 are not connected.

Uploading code to the ESP32 TouchDown

For FreeTouchDeck installation instructions see: https://github.com/DustinWatts/FreeTouchDeck/wiki/1.-Installation

For other code: The ESP32 TouchDown uses the same configuration as an ESP32 Dev Module. So you can use those board definitions to upload your own code to the ESP32 TouchDown:

Open Source

Everything about the ESP32 TouchDown is open source. This means I provide you will all the designs I make. In this repository, you will find the KiCad project, including schematic, and board layout. Also, the complete BOM is available to you. I have included the datasheets of all the hardware used.

Support Me

If you like what I am doing, there are a number of ways you can support me.

Platform	Link
	You can follow me on Twitter: @dustinwattsnl
	You can subscribe to my channel on Youtube: /dustinWatts
	You can support me by becoming a patron on Patreon: https://www.patreon.com/dustinwatts
	You can make a one time donation using PayPal.me: https://www.paypal.me/dustinwattsnl