ESP32 Clock

This is a YAML config file + driver for a clock based on several LED segment displays driven by SN74HC595 shift registers.

Hardware

Connect the shift registers like this, or adapt the pin config as needed:

• Data input (DIO) to ESP:
  • GPIO23 (first display),
  • GPIO19 (second display),
  • GPIO22 (third display),
  • GPIO21 (fourth display)
• Shift clock input (SCK) to ESP GPIO18 (all displays)
• Latch / register clock input (RCK) to ESP GPIO5 (all display)

Keep in mind that the ESP32 is a 3.3V device when connecting to a 5V display. The shift registers should handle the 3.3V signals from the ESP, annd in some cases, 3.3V can also be used to power the displays at a lower brightness.

Setup

Note: the QSPI driver in esphome is (as of 2024-01-28) not yet in the released package. Install a suitable version directly from github with: pip install "esphome @ git+https://github.com/esphome/esphome@1fef769496ed89c0062d8e70f5964b8318ba4550"

Set the board type in the YAML (default should also work on most ESP32 devices) Adapt the config as needed for the fallback AP and if wanted, api key. Create a secrets.yaml containing this:

wifi_ssid: "ssidhere"
wifi_password: "keyhere"

Adapt the config flags reverse, common_cathode, and segment_first in the component configuration in the main YAML for your display type.

Build and upload the config with esphome CLI, or the dashboard. See the ESPHome CLI Getting Started Guide how to do that.

License

The driver in components/ is directly based on the existing MAX7219 driver in ESPHome and as such subject to the GPLv3 and MIT licenses, as outlined in the LICENSE document (also copied from ESPHome).

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