Many off-the-shelf devices are powered with ESP8285 or ESP8266 chips, in devices with white-label firmware provided by a company called Tuya. The project tuya-convert exists to hack these devices and enable us to load custom firmware.
Firmware options include:
- Tasmota - the original; many devices are known and pin configurations listed here
- Espurna - an alternative which has a nice Web UI and is easily configurable with custom builds
- ESP Home - a versetile firmware which supports a lot of different chips in practice, and has many great features for the advanced user
I use ESP Home both for NodeMCU type ESP8266 boards, and for off-the-shelf devices running Tuya.
How to flash a device with this repo.
- Extract the ID for the above table using
make flash - Configure a custom image using the esphome templates
- Build the custom image
- Flash and ensure device appears on wifi network
- Watch the MQTT logs using
DEVICE=blah make logs
Use esphome templating to
create a template for the device. Ensure to import the _esphome.yaml package, which has the
common configuration, and also the sensor packages for your use-case.
An example device YAML:
---
substitutions:
device_id: '0fe8ed'
device_name: 'ESP8622 Server Closet'
static_ip: '192.168.20.63'
esp8266:
board: nodemcuv2
packages:
base: !include ../packages/_esphome.yaml
dht22: !include
file: ../packages/dht22.yaml
vars:
room: 'Server Closet'
data_pin: 1
A Makefile is included to simplify the interface.
Render the template configured for device c0a4ba, and build the firmware binary:
DEVICE=c0a4ba make compile
Under the hood, this calls esphome compile command:
esphome compile templates/10945b.yaml
> esptool.py --before default_reset --after hard_reset --baud 460800 --chip esp8266 write_flash 0x0 774ba4/.pioenvs/774ba4/firmware.bin
esptool.py v2.8
Serial port /dev/ttyUSB0
Connecting....
Detecting chip type... ESP8266
Chip is ESP8266EX
Features: WiFi
Crystal is 26MHz
MAC: 84:f3:eb:c0:a4:b4
Uploading stub...
Running stub...
Stub running...
Configuring flash size...
Compressed 433552 bytes to 315828...
Wrote 433552 bytes (315828 compressed) at 0x00000000 in 28.8 seconds (effective 120.5 kbit/s)...
Hash of data verified.
Leaving...
Hard resetting via RTS pin...
Once a device has been flashed to ESP Home, one can update directly from the CLI via OTA on the network. If that is failing, switch to flash via USB.
DEVICE=c0a4ba make upload
Leverage the use_address attribute on ESPHome's wifi component to connect to a specific IP for the
OTA update.
For example, moving a device from 192.168.20.64 to 192.168.20.205:
---
substitutions:
device_id: '776b6e'
device_name: 'ESP8266 Bread Chamber'
static_ip: '192.168.20.205'
esp8266:
board: nodemcuv2
packages:
base: !include
file: ../packages/_esphome.yaml
vars:
use_address: '192.168.20.64'
Notes and pinouts for various components I've used with ESP32/ESP8266.
Pin configuration for an OLED 128x64 display. These can run on either i2c or SPI bus; this configuration uses i2c.
From the screen-side, pins left-to-right:
Data- i2c data pin, or SPI MOSIClk- SPI clockSA0- Select Address / Data Command (akaDC)Rst- ResetCS- SPI chip select3v3- 3.3v inputVinGnd
Required pin config from the ST7735 esphome.io doc:
spi:
clk_pin: 25
mosi_pin: 26
display:
- platform: st7735
reset_pin: 21
cs_pin: 22
dc_pin: 23
ST7735 display driver configuration, for use with a TZT 1.8" TFT 160x128 display.
From the screen-side, pins left-to-right:
LED- Connect to 3v or 5vSCK- SPI clock (akaCLK)SDA- Bus input (aka SPIMOSI)A0- Address Select / Data Command (akaDC)RESETCSGNDVCC
Required pin config from the ST7735 esphome.io doc:
spi:
clk_pin: 25
mosi_pin: 26
display:
- platform: st7735
reset_pin: 21
cs_pin: 22
dc_pin: 23
The Wemos IR shield is transmitter and receiver in one convenient board. It also has an LED to show when IR signals are being sent.
| Pin | GPIO | |
|---|---|---|
| Send | D3 | 0 |
| Recv | D4 | 2 |
The LOLIN D32 Pro has a TFT connector, as does the I2C/TFT hat. The pinout for this connector follows. The colours correspond to the 10 pin TFT connector cable that fits the LOLIN.
| Colour | Name | Pin | Desc | |
|---|---|---|---|---|
| 1 | Black | TFT_LED |
IO32 |
Connect to 3v or 5v |
| 2 | Red | GND |
||
| 3 | White | TFT_RST |
IO33 |
TFT Reset |
| 4 | Yellow | TFT_DC |
IO27 |
Data Command (aka DC) / Address Select (aka A0) |
| 5 | Orange | MOSI |
IO23 |
SPI input (aka SDA) |
| 6 | Green | MISO |
IO19 |
SPI output |
| 7 | Blue | SCK |
IO18 |
SPI clock (aka CLK) |
| 8 | Purple | 3V3 |
aka VCC |
|
| 9 | Grey | TFT_CS |
IO14 |
TFT SPI chip select |
| 10 | Brown | TS_CS |
IO12 |
Touchscreen SPI chip select |
| Colour | Name | Pin | Desc | |
|---|---|---|---|---|
| 1 | Brown | TS_CS |
IO12 |
Touchscreen SPI chip select |
| 2 | Grey | TFT_CS |
IO14 |
TFT SPI chip select |
| 3 | Purple | 3V3 |
aka VCC |
|
| 4 | Blue | SCK |
IO18 |
SPI clock (aka CLK) |
| 5 | Green | MISO |
IO19 |
SPI output |
| 6 | Orange | MOSI |
IO23 |
SPI input (aka SDA) |
| 7 | Yellow | TFT_DC |
IO27 |
Data Command (aka DC) / Address Select (aka A0) |
| 8 | White | TFT_RST |
IO33 |
TFT Reset |
| 9 | Red | GND |
||
| 10 | Black | TFT_LED |
IO32 |
Connect to 3v or 5v |
Dallas 1-wire protocol temperature sensors, such as the DS18B20.
These are fast to read, and are fully enclosed and therefore safe outdoors.
Many sensors can be put on the same data line (hence "1-wire protocol"); each device is identified by a hexidecimal address, which esphome will print on startup when it scans the Dallas bus.
For indoors usage, the DHT22 is preferred as no circuit is required - the DHT22 pins attach directly
the ESP board. The exception is the Raspberry Pi - DHT22 support is terrible (the Adafruit
libraries), so preference is to use the w1thermsensor
project as in mafrosis/w1therm.
┌───────────────┐
│ DS18B20 │
│ │
│ RED YEL BLK │
└───────────────┘
│ │ │
│ │ │
│ │ │
┌─────────┐ │
│ 2.2k R │ └┐
└─────────┘ │
│ │ │
│ │ │
│ │ │
3V D5 GND
The SwiCago/HeatPump project made it possible to control
Mitsubishi aircon units via serial, on a connector named CN105. A kind soul wrapped this library
in esphome, as found at geoffdavis/esphome-mitsubishiheatpump.
This usage of the library has been done with the ESP8266 Wemos D1 mini v3.1 as the control board.
Wiring per the demo circuit:
┌────────┐ ┌───────────┐
│ CN105 │ │ Wemos D1 │
│ ├─┐ │ │
│ 1 12V │x│ ┌──────┤ 5V 3V3 │
│ 2 GND │-├─────┼──────┤ GND D8 │
│ 3 5V │-├─────┘ │ D4 D7 │
│ 4 TX │-├─────┐ │ D3 D6 │
│ 5 RX │-├───┐ │ │ D2 D5 │
│ ├─┘ │ │ │ D1 D0 │
│ │ │ └──────┤ RX A0 │
└────────┘ └────────┤ TX RST │
│ │
└───────────┘
GND black brown
5V yellow red
TX green orange
RX blue yellow
https://www.freetronics.com.au/products/light-sensor-module https://cdn.shopify.com/s/files/1/0045/8932/files/TEMT6000.pdf
┌─┬───┬┬───┬┬───┬─┐
│ │GND││DAT││VCC│ │
│ └───┘└───┘└───┘ │
│ ┌───┐ │
│ . └───┘ . │
│( ) ( )│
└─'─────────────'─┘
A digital microphone using the i2s sound bus (which is similar to i2c, but unrelated).
L/R left/right channel (needs to be grounded not floating)
WS i2s word select
SCK i2s clock
SD i2s data
VCC 3.3V
GND ground
This neat little ESP32-C6 has a LED screen attached and a built-in LED.
https://www.waveshare.com/wiki/ESP32-C6-LCD-1.47
┌─────┐
┌─────┤ ├─────┐
├─┐ │ │ ┌─┤
│ │ └─────┘ │ │
├─┘ └─┤
│ │
│5V TXD│
│GND RXD│
│3V3 13│
│0 12│
│1 23│
│2 ┌─────┐ 20│
│3 │ │ 19│
│4 │ │ 18│
│5 └─────┘ 9│
│ │
└─────────────────┘
The ESP-C6 is a single core SOC, which means wifi and sensor reading must share a core. Make sure any sensor read intervals are long enough not to overload the CPU.
XIAO ESP32 C6 SuperMini template
https://wiki.seeedstudio.com/xiao_esp32c6_getting_started/
┌─────┐
┌┬─┬──┤ ├──┬─┬┐
│└─┘ │ │ └─┘│
│D0 └─────┘ 5V│
│D1 GND│
│D2 ┌───────┐ 3V3│
│D3 │ │ D10│
│D4 │ │ D9│
│D5 │ │ D8│
│D6 └───────┘ D7│
└─────────────────┘
The newer ESP32-C6 supports Zigbee/Thread, and so the radio can be configured for that protocol rather than wifi. It's not possible to use wifi AND zigbee at the same time.
Example in commit 1a07bd2.
Zigbee is worth exploring for battery powered devices, as it has much lower power requirements than Wifi.
GND white
5V red
DI green
BI blue
The two data pins are for primary data and backup data. Only the primary DI needs to be connected to the ESP controller. The backup connector links each LED with the next-but-one, if the LED strip is cut and reconnected then all four wires must be connected.
Supplied wires are AWG22 gauge with 2.54mm pitch connectors.
A run of 100 LEDs at 100% brightness can draw a large amount of power - nearly 3 amps at 5V in testing. According to the spec, power requirement is 18 watts per metre.
Really long runs need to have power injected along the LED strip:
Using neopixelplus requires the ESP8266 GPIO3 pin. On the Wemos D1 mini this is labelled RX.
https://www.wemos.cc/en/latest/s3/s3_mini.html
┌─.───────────────┐
│( ) 3.3V│
│ ' ┌─┐ GND│
│ │ │ SCL│
│ . └─┘ SDA│
│( ) ADDR│
└─'───────────────┘
Operates in range 3V-5V.
The ADDR pin enables two of these to be operated on the same i2c bus. Pull the pin high/low to differentiate the address.
High 0x5C
Low 0x23
Notes on LOLIN battery headers Charging batteries Deep Sleep
mosquitto_pub -h 192.168.1.198 -m 'ON' -t 707a3c/ota_mode -r