Bitcoin Price 2.9" ePaper for ESPHome

Here's is a portable, battery-powered 2.9" ePaper display of the current Bitcoin price from Coingecko, powered by ESPHome.

firebeetle2.yaml is an ESPHome configuration for a Firebeetle2 ESP32-C6 with a Waveshare 2.9" black and white ePaper display. The configuration tells the Firebeetle2 to periodically wake up, update the display with sensor data, then go back to deep sleep. My device is awake about 8 seconds per hour, which I'm hoping will mean long battery life.

Firebeetle2 ESP32-C6

This is a great device for ESPHome. It's widely available, has Wifi6, deep sleep and costs only £8 / $10. As an ESP32-C6 device, the Firebeetle2 is not widely supported by ESPHome, yet. My configuration shows how to get it working, at least for now. (Note, there are other Firebeetle2 devices that are not the C6 chip).

Features

• Bitcoin Price Display: Fetches and displays the current Bitcoin price from the public Coingecko API, via a Home Assistant entity
• Status Monitoring: Monitors and displays the battery percentage and wifi signal on-screen with icons.
• Deep Sleep for long battery life: The device wakes up every 60 minutes, gets the current Bitcoin price, updates the ePaper screen, then goes back to sleep. My device is only awake about 8 seconds each hour.

Hardware Installation

Controller: Firebeetle2 ESP32-C6

Purchase: Around £8 at AliExpress: https://vi.aliexpress.com/item/1005006449798923.html

Notes: Connect the Firebeetle2 to the ePaper as listed in the YAML. Something like...

(Waveshare ePaper board connector label >> wire colour >> Firebeetle2 pin >> YAML label)

1. BUSY >> Purple >> 3 >> busy_pin
2. RST >> White >> 2 >> reset_pin
3. DC >> Green >> 1 >> dc_pin
4. CS >> Orange >> 7 >> cs_pin
5. CLK >> Yellow >> 4 >> clk_pin
6. DIN >> Blue >> 6 >> mosi_pin
7. GND >> Brown >> G >> not mentioned
8. VCC >> Grey >> 3.3 >> not mentioned

The onboard LED does not light up except when the device is charging the battery, presumably to save power

Display: Waveshare 2.9" black and white display.

Purchase: £22 at Amazon UK: https://amzn.eu/d/aKlZQN6

Notes: The project could be modified for other displays, but:

1. Waveshare ePaper seems to work more reliably and is better supported than cheaper 3rd party ePaper
2. Don't be tempted by a black/white/red display. They take around 20 seconds to refresh the display, which is too long.

The display comes with a cable from the ePaper to Dupoint wires for connecting to the Firebeetle2.

Battery

Purchase: £8 for this EEMB battery from Amazon UK: https://amzn.eu/d/aDqnDVv

Notes: Lipo 2000mah battery. Buy one with built-in protection against overcharging or rapid discharge etc.

Important: Make sure the battery polarity on the JST connector (red and black wires) matches what the Firebeetle2 needs BEFORE plugging in. The red and black wires are often the wrong way around.

Stand

I designed a little stand for this setup: https://makerworld.com/en/models/990598#profileId-966064

Based on an original design from https://www.printables.com/model/266626-waveshare-29-inch-e-ink-screen-stand

Software Installation

1. Track the Bitcoin price

   Add a Bitcoin entity to track the Bitcoin price in Home Assistant

   In /homeassistant/configuration.yaml, add:

   sensor:
     # Bitcoin Current Price (USD)
     - platform: rest
       name: Bitcoin Current Price
       unique_id: bitcoin_current_price
       resource: https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=usd
       value_template: "{{ value_json.bitcoin.usd }}"
       unit_of_measurement: "USD"
       scan_interval: 3600  # Update once per hour

2. Create a toggle for deep sleep

   HA > Settings > Devices & Services > Helpers > Create Helper >> Toggle

   Name your new helper entity "firebeetle_enable_sleep" for a result named "input_boolean.firebeetle_enable_sleep", to match what's in the YAML. When this setting is off, the Firebeetle2 will remain awake and ready for OTA updates and monitoring. When it's on (either immediately when turned on, or on when the device boots), the device will sleep as configured.

3. Configure secrets.yaml

   Use a file secrets.yaml file to store your WiFi credentials, API encryption key, and OTA password.

   Here is an example secrets.yaml:

   wifi_ssid: "your_wifi_ssid"
   wifi_password: "your_wifi_password"
   
   firebeetle2_api_encryption_key: "your_api_encryption_key"
   firebeetle2_ota_password: "your_ota_password"

   Replace the placeholder values with your actual credentials.

   Place secrets.yaml in the same directory as your ESPHome configuration files.

   Add secrets.yaml to .gitignore, if needed.

4. Compile and Install: Use the ESPHome dashboard to compile and install the configuration in the YAML "firebeetle2.yaml" to your Firebeetle2.