ESP8266X2PAV (ESP8266 Hexadeca-Squared Pixel Art Viewer)

A 16×16-dotted pixel art viewer with ESP-WROOM-02 and Unicorn HAT HD.

Instruction

This device can display images from GIF files. Animated GIFs are also supported.

A web application is provided. You can access http://esp8266x2pav.local:8080/ (as default) with a web browser and upload your GIF file. Both the width and the height of the image must be within 32 pixels, and the file size must be within 64KiB. The image is cropped if its width or height is over 16 pixels.

The next image will be displayed automatically after the specified duration has elapsed (and after the specified loop times in the case of animation GIF). Moreover, you can force to display the next image by pressing the button.

It goes to sleep mode after the specified duration has elapsed and be resumed by pressing the button.

Web API specification

Here is the Web API specification generated from "openapi.yaml".

Hardware

Components

ESP-WROOM-02
Unicorn HAT HD
LDO module (3.3V): M-3V3SIP
Resistors: 10kΩ×6
Wires, connectors, switches, etc...

Schematic

Example

Software

Build and transfer

Clone the source code and open the project file "ESP8266X2PAV.ino" with Arduino IDE.

You must import ESP8266 board.

Also, you must modify "credential.h" according to your situation.

HOSTNAME and PORT if you like.
- The URL to get version information will be http://esp8266x2pav.local:8080/version if you don't modify.
STA_SSID and STA_PASSWORD according to your Wi-Fi access point setting.
- If you'd like to assign static IP address to the device, uncomment #ifdef STATIC_ADDRESS and edit values of STATIC_ADDRESS_***.

You can build the source code with following configuration.

Attribute	Value
Board	Generic ESP8266 Module
Builtin Led	2
Upload Speed	921600
CPU Frequency	80 MHz
Crystal Frequency	26 MHz
Flash Size	4MB (FS:3MB OTA:~512KB)
Flash Mode	DOUT (compatible)
Flash Frequency	40 MHz
Reset Method	dtr (aka modemcu)
Debug port	Disabled
Debug Level	None
lwIP Variant	v2 Lower Memory
VTables	Flash
C++ Exceptions	Disabled (new aborts on oom)
Erase Flash	Only Sketch
NONOS SDK Version	nonos-sdk 2.2.1+119 (191122)
SSL Support	Basic SSL ciphers (lower ROM use)
MMU	32KB cache + 32KB IRAM (balanced)
Non-32-Bit Access	Use pgm_read macros for IRAM/PROGMEM

Then, you can transfer the firmware binary data to ESP-WROOM-02 by any means.

Acknowledgement

License

These codes are licensed under MIT License.

obono/ESP8266X2PAV