HUD-like WiFi Sync Clock / Transparent Dot Matrix Display

HUD like clock that acquires current time via WiFi. Four common 8x8 dot matrix display units (MAX7219 driver) are used. The display unit is tilted backward for directly invisible.

• Four connecting 8x8 dot matrix display unit that uses MAX7219 driver
• ESP32 micro controller (you can use any micro controller that can handle SPI interface)
• Acrylic plate (thickness = 1mm, 165 x 75mm)

• You can print the body without support.
• Prepare acrylic plate, W=165mm, H=75mm or around.
• It is better to paint the body with matte black paint. I used extremely low reflectance paint, MUSOU BLACK, around the unit and top surface of the body.

Connect your micro controller to the display unit.

• Install MAX72XX library to your Arduino IDE.
• In my case, I connected DIN - 16, CS - 17, CLK - 21. The connection is changeable in the source code. See lines 115-117 as follows.

#define CLK_PIN   21  // or SCK
#define DATA_PIN  16  // or MOSI
#define CS_PIN    17  // or SS

• Configure your WiFi in the source code. You can use SmartConfig smartphone app to do it also.

#define WIFI_SSID "SSID" // your WiFi's SSID
#define WIFI_PASS "PASS" // your WiFi's password

• Place the micro controller outside of the body. You can use any micro controller.

• Place the display unit to the body.
• Insert the Acrylic plate.