The Display Station 2024 Model A (DS24a) is based on the ESP32-2432S028R, which provides an ultra low cost interface into your own compute.
Variation
There are other display devices on the market called ESP32-2432S028R, the DS24a is the ESP32-2432S028R version with a ILI9341 display.
Limitations
Due to the extreme lack of compute power and memory on this device (unlike some other ESP32 boards, this does NOT have PSRAM), hacking the board takes a lot of time. Currently we need to multiplex some heavy apps so they can only run one at a time (e.g. Bluetooth radio and the LCD display). Also we do not have time to get some peripherals work:
Even with those limitations we still believe the DS24a will revolutionise the digital world by delivering, for the first time, compute that people can fully control and benefit from into their homes.
Supplier
There are many ESP32-2432S028R devices available online that are very similar to the DS24a, with names like Cheap Yellow Displays (CYD), Guition / Sunton Smart Displays etc. most have small differences with each other.
DS24a shown above is standing up vertically on low-cost plastic spacers for better display visibility and heat dissipation.
DS24a does NOT have a battery interface.
There is a Light Dependent Resistor (to measure surrounding light level) in the front Upper Right Corner of the board.
DS24a's low cost screen means the displayed QR Code CANNOT be seen clearly at an angle (but for our use as an Activity Marker this is actually an advantage!).
1. Processor
Teh DS24a processor is built with the ESP-WROOM-32 module.
Dual-core ESP32-D0WDQ6 processor
40MHz Crystal Oscillator
4MByte Flash Storage
Meandered Inverted-F Antenna
Note:
DS24a does NOT support the use of lower frequency crystal oscillators (e.g. 26MHz).
DS24a does NOT take advantage of ESP-WROOM-32's ability to have external Flash (up to 4Mbyte) NOR have external RAM (up to 4Mbyte).
Pin-Outs
Despite its ultra low-cost, the ESP-WROOM-32 has builtin in Bluetooth and WiFi (with integrated antenna) with a rich set of input/output pins.
To display images on the ESP32-2432S028R in Landscape (320x240) mode instead of the default Portrait mode (240x320), rotating the output by 270 degree before displaying the output.
Note we rotate output image by 270 degrees instead of 90 degrees, because we want the side of the board with IO connectors to be on top facing up and the plastic spacers (functioning as legs holding up the board) are attached to the side of the board without IO connectors at the bottom facing down.
Above shows DS24a acting as a Activity marker performing the TRIPLE role of
a QR Marker (displaying QR Code)
a Radio Marker (broadcasting Bluetooth signals)
a Radio Scanner (scanning WiFi and Bluetooth signals)
3. Other Components
The DS24a is very expandable supporting a lot of different inputs and outputs.
Below is a comprehensive of labelling of components of a similar model (which has some differences e.g. the audio IC is 8002A instead of 8002, it does NOT have a USB Type-C port, it does NOT have IO22 exposed on two IO connectors etc.).
Although there are many esp32 based display devices, the DS24a can only be a ESP32-2432S028R.
Our focus is on the ESP32-2432S028R model which has the best open software support, but there are a number of different models with a ESP-WROOM-32 chip and a touch display (which your local citizen ecosystem might support), most of these devices have the same display resolution of 240x320 but with different screen sizes, touch ability and connectors.
BECAREFUL some of the CYDs use Parallel interface (instead of the SPI interface) which is NOT support in ESPHome yet:
There are 3 white-coloured 4-pin IO connectors on the edges of the DS24a for attachment of external peripherals to varies input/output pins.
The DS24a comes bundled with only one 4-pin breakout cable for one of those 3 connectors, we suggest using the cable on the connector with the IO22 and IO27 pins for your input/output needs.
There are 3 LEDs clustered together on the back of DS24a, by default all 3 colours are turned ON, so it will emit a WHITE light as a whole. We need to turn one or more of the LEDs OFF get different colours.
RGB LED
GPIO
Red
4
Green
16
Blue
17
The following colours are used to indicate the mode of DS24a:
