Quickly Develop GUI-Based Gadgets with the gCore Platform

Some Internet of Things devices, or gadgets, benefit from a user interface. Any of these using an LCD have some form of graphical user interface (GUI). However, building a GUI-based gadget can be daunting, given the complexity of driving a large display. Thanks to the work of Dan Julio, this part of IoT design is getting easier with gCore — a GUI-based gadget platform.

On danjuliodesigns LLC's website, we noticed an intriguing aspect of this project unrelated to the technical details. Julio's past work experience includes graphics work. The first job listed was designing computer graphics processors for HP Workstations--back when HP had on-site fabs in some of their locations!

The gCore board is 95 x 69 x 11 millimeters. A large 3.5" 480x320 pixel LCD covers one entire side of the board. On the opposite side is a popular IoT microprocessor and hardware to support the display.

An ESP32 WROVER module is the central processor for gCore. It interfaces to the LCD through an 80 MHz SPI to 8-bit parallel bus converter. You can communicate with gCore either by the built-in USB-to-Serial converter. Or, you can use the GPIO and I2C pins along the bottom of the PCB. Additionally, there is a Qwiic/Grove/Stemma connector on board.

Over I2C, the ESP32 talks to the LCD's capacitive touch panel and an EFM8 microcontroller. This co-processor handles several tasks such as time/alarm keeping with an RTC, power management (with soft power), voltage/current monitoring, and controlling the brightness of the LCD's backlight.

This platform supports the Arduino IDE with ESP32 package or Espressif's IDF. In addition, Julio provides a modified version of Adafruit's ILI9488 library. You will need other libraries, so check the documentation page for a complete list.

Currently, gCore is not available for sale or to build. However, Julio says the intention is to make it available soon. For now, check out the extension resources in the gCore GitHub repository. It contains a wide variety of example applications for gCore.