# node-blink1-async

Programmatically controlling [blink(1) USB LED devices](https://blink1.thingm.com/) is simple using **node-blink1-async**. Much of the API is asynchronous (i.e., returns Promise that you can await on) and fully [documented](https://ros2jsguy.github.io/node-blink1-async/). This module has been tested on Mac, Windows 10, and Ubuntu Linux on a Raspberry Pi 4. 

![blink(1) USB led on raspberry pi 4](docs/blink1-raspi.jpg "blink(1) USB led on raspberry pi 4")


If you perfer a JS callback style API consider [node-blink1](https://www.npmjs.com/package/node-blink1). 


# Prerequisites
* Node (v12+)
* blink(1) USB led device

Ensure your blink(1) is fully functional using the [blink(1) utilities](https://blink1.thingm.com/downloads/). 

# Install
```
npm install https://github.com/ros2jsguy/node-blink-async
```

## Linux Users
Your device may need libusb installed:
```
sudo apt install libusb-1.0-0
```

See node-hid's [instructions for compiling from source](https://github.com/node-hid/node-hid#compiling-from-source)
You may find the 51-blink1.rules file useful in your device configuration process. 

# TypeScript Example
```
import {Blink1, Blink1_LEDN, BlinkRate} from '@ros2jsguy/node-blink1-async';

async function example() {
  // list all blink(1) devices
  console.log('devices; ', Blink1.devices());

  // output the version info of the default blink(1) device
  let blink1: Blink1 = new Blink1();
  console.log("version: " , await blink1.version() );

  console.log('set color: red', await blink1.setRGB(255));
  console.log('read rgb: ', await blink1.rgb(Blink1_LEDN.LEDA));
  await Blink1.delay(2000);

  console.log('Blink green at VERY_FAST rate (100 ms) for 5 seconds');
  await blink1.blink(0, 255, 0, BlinkRate.VERY_FAST);
  await Blink1.delay(5000);
  
  console.log('Blink blue at SLOW rate (1000 ms) for 5 seconds');
  await blink1.blink(0, 0, 255, BlinkRate.SLOW);
  await Blink1.delay(5000);

  console.log('Show solid yellow for 5 seconds');
  await blink1.blink(255, 255, 0);
  await Blink1.delay(5000);

  // turn off the blink(1) output
  await blink1.off();

  // access the display pattern at line-1
  console.log('Color pattern (line-1):', await blink1.readPatternLine(1));

  // clear the memory of all display patterns.
  console.log('Clearing pattern');
  await blink1.clearPattern();

  // confirm that display patterns are cleared
  console.log('Color pattern (line-1):', await blink1.readPatternLine(1));

  // close and release the blink(1) device
  await blink1.close();

  console.log('completed');
}
```

# Developer Notes
I develop mostly in TypeScript and prefer using modern JS features when I have the option. 
Working directly with the node-blink1 package which has been around for awhile, felt too
retro for my liking, e.g., no jsdoc, callback-based api... 
I mean no disrespect to the node-blink1 author(s) who's priority 
for backward compatibility supercedes breaking the package just to use a new
wizbang language feature. While developing a robot using TypeScript 
on a Raspi4 I wanted to integrate an old Blink1 led from my kit
into the design. That led me to creating this package that makes it easier to 
to asynchronously control a Blink1 LED from TypeScript.

# Credits
This package uses the [node-blink1](https://www.npmjs.com/package/node-blink1) package to perform the low level control of Blink1 devices