Project 34b:
Ada 3651 Triple Expansion Board

       v1.1 Schematic                                v1.1 Board Layout                               v1.1 PCB Top                                  Video of Operation

v1.1 Bill of Materials

Description:

This is a triple expansion board for the Adafruit 3651 3.5" TFT-TS Display (V2).

The 3.5" TFT display is on top of the PCB and a Feather microcontroller like the Feather M4 Express or Feather ESP32 is placed opposite of it on the bottom.

Two Featherwing slots surround the microcontroller slot: perhaps Ultimate GPS and Joy Featherwing or any of the other many Featherwings could be used.

Features:

TFT-TouchScreen display is placed on the top of the board using long stacking headers through the PCB to the Feather microcontroller on the other side.

A microcontroller and two expansion boards (Featherwings) are attached to the bottom of the PCB.

Slide dipswitches are placed between the left and right Feather-sized 12-pin and 16-pin connectors; enable only the lines you need from the central Feather microcontroller/Featherwing TFT-TS connector to the Left or Right expansion connectors. Example: we only use TX and RX from the GPS Featherwing so we can set the other dipswitches to the Off position.

Each of the expansion connectors as well as the microcontroller connector contain 2 rows of pins in case you wish to jumper your own routes.

Production:

The PCB back from fabrication has been populated and tested.

Below we see the components of Project 9 (Bakk Trakker) installed on the expansion board and working well. Click each for larger images.

Code:

You may wish to try out this code, GPS_HardwareSerial_EchoTest.ino, on the 3.5" v2 display. (The v1 display uses different TFT and TS drivers that have been commented out in the code.)