node-red-contrib-lcd20x4-i2c
Version:
Driver for 20x4 HD44780 LCD Display connected via I2C PCF8574
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Markdown
This node is a driver for 20x4 HD44780 LCD Display connected via I2C PCF8574
Dependencies: SMBus, enable i2c in raspi-config
```
sudo apt-get install python-smbus
sudo raspi-config
Interfacing Options>I2C>Enable
```
This node will accept an object `msg.payload.msgs`. If the object passed does not contain 4 lines, the difference is filled with blank lines.
Line data structure:
* msg must be a string.
* If msg is more than 20 characters the node will handle scrolling.
* pos (position) is optional and must be a number with any value between 1-20. This value is used for offsetting text, but you can also insert spaces in to msg instead of supplying pos.
* If pos is not supplied it will default to 1.
* center is optional and must be a boolean value passed as a string
* If pos and center are both set, center will override pos.
If there is an error it will be logged to Node-RED and display an error on the LCD screen.
Object format:
```
msg.payload = {
msgs: [
{
msg: "string",
pos: number,
center: "boolean"
},
{
msg: "string",
pos: number,
center: "boolean"
},
{
msg: "string",
pos: number,
center: "boolean"
},
{
msg: "string",
pos: number,
center: "boolean"
}
]
};
```