OLED JS Pi over i2c-bus
This is fork of package oled-js-pi
that works thru i2c-bus
package and not use package i2c
.
A NodeJS driver for I2C/SPI compatible monochrome OLED screens; to be used on the Raspberry Pi! Works with 128 x 32, 128 x 64 and 96 x 16 sized screens, of the SSD1306/SH1106 OLED/PLED Controller (read the datasheet here).
This based on the Blog Post and code by Suz Hinton - Read her blog post about how OLED screens work!
OLED screens are really cool - now you can control them with JavaScript!
Raspberry Pi allows for software I2C. To enable software I2C, add dtoverlay=i2c-gpio,bus=3
to /boot.config.txt
. The software I2C would be available on bus
no 3
where the SDA
is on pin GPIO23
/BCM 16
and SCK
is on pun GPIO24
/BCM 18
.
If you haven't already, install NodeJS.
npm install oled-i2c-bus
For SH1106
, if you get an error:
"Error: , Remote I/O error"
You might have to lower the baudrate by adding the following line to /boot/config.txt
and rebooting the Pi
dtparam=i2c_baudrate=10000
This is a known issue with Raspberry Pi as noted in Raspberry Pi I2C hardware bug. Alternatively, use software I2C.
Hook up I2C compatible oled to the Raspberry Pi. Pins: SDA and SCL
var i2c = require('i2c-bus');
var oled = require('oled-i2c-bus');
var opts = {
width: 128,
height: 64,
address: 0x3D,
bus: 1,
driver:"SSD1306"
};
var i2cbus = i2c.openSync(opts.bus)
var oled = new oled(i2cBus, opts);
// do cool oled things here
Check your screen's documentation...
Fills the buffer with 'off' pixels (0x00). Optional bool argument specifies whether screen updates immediately with result. Default is true.
Usage:
oled.clearDisplay();
Lowers the contrast on the display. This method takes one argument, a boolean. True for dimming, false to restore normal contrast.
Usage:
oled.dimDisplay(true|false);
Inverts the pixels on the display. Black becomes white, white becomes black. This method takes one argument, a boolean. True for inverted state, false to restore normal pixel colors.
Usage:
oled.invertDisplay(true|false);
Turns the display off.
Usage:
oled.turnOffDisplay();
Turns the display on.
Usage:
oled.turnOnDisplay();
Draws a pixel at a specified position on the display. This method takes one argument: a multi-dimensional array containing either one or more sets of pixels.
Each pixel needs an x position, a y position, and a color. Colors can be specified as either 0 for 'off' or black, and 1 or 255 for 'on' or white.
Optional bool as last argument specifies whether screen updates immediately with result. Default is true.
Usage:
// draws 4 white pixels total
// format: [x, y, color]
oled.drawPixel([
[128, 1, 1],
[128, 32, 1],
[128, 16, 1],
[64, 16, 1]
]);
Draws a one pixel wide line.
Arguments:
Optional bool as last argument specifies whether screen updates immediately with result. Default is true.
Usage:
// args: (x0, y0, x1, y1, color)
oled.drawLine(1, 1, 128, 32, 1);
Draws a filled rectangle.
Arguments:
Optional bool as last argument specifies whether screen updates immediately with result. Default is true.
Usage:
// args: (x0, y0, x1, y1, color)
oled.fillRect(1, 1, 10, 20, 1);
Draws a bitmap using raw pixel data returned from an image parser. The image sourced must be monochrome, and indexed to only 2 colors. Resize the bitmap to your screen dimensions first. Using an image editor or ImageMagick might be required.
Optional bool as last argument specifies whether screen updates immediately with result. Default is true.
Tip: use a NodeJS image parser to get the pixel data, such as pngparse. A demonstration of using this is below.
Example usage:
npm install pngparse
var pngparse = require('pngparse');
pngparse.parseFile('indexed_file.png', function(err, image) {
oled.drawBitmap(image.data);
});
This method is provided as a primitive convenience. A better way to display images is to use NodeJS package png-to-lcd instead. It's just as easy to use as drawBitmap, but is compatible with all image depths (lazy is good!). It will also auto-dither if you choose. You should still resize your image to your screen dimensions. This alternative method is covered below:
npm install png-to-lcd
var pngtolcd = require('png-to-lcd');
pngtolcd('nyan-cat.png', true, function(err, bitmap) {
oled.buffer = bitmap;
oled.update();
});
Draw an RGBA coded image at specific coordinates. This only supports a monochrome OLED so transparent pixels must be 100% transparent, off pixels should have an RGB value of (0, 0, 0), and pixels with any color value will be considered on.
Use a library such as pngjs to read a png file into the required rgba data structure.
Example:
const fs = require('fs');
const PNG = require('pngjs').PNG;
const i2c = require('i2c-bus');
const oled = require('oled-i2c-bus');
var i2cBus = i2c.openSync(0);
var opts = {
width: 128,
height: 64,
address: 0x3C
};
var display = new oled(i2cBus, opts);
display.clearDisplay();
display.turnOnDisplay();
fs.createReadStream('./test.png')
.pipe(new PNG({ filterType: 4 }))
.on('parsed', function () {
setInterval(() => { drawImage(this) }, 1000);
});
function drawImage(image) {
let x = Math.floor(Math.random() * (display.WIDTH) - image.width / 2);
let y = Math.floor(Math.random() * (display.HEIGHT) - image.height / 2);
display.drawRGBAImage(image, x, y);
}
Scrolls the current display either left or right. Arguments:
Usage:
// args: (direction, start, stop)
oled.startscroll('left', 0, 15); // this will scroll an entire 128 x 32 screen
Stops all current scrolling behaviour.
Usage:
oled.stopscroll();
Sets the x and y position of 'cursor', when about to write text. This effectively helps tell the display where to start typing when writeString() method is called.
Call setCursor just before writeString().
Usage:
// sets cursor to x = 1, y = 1
oled.setCursor(1, 1);
Writes a string of text to the display.
Call setCursor() just before, if you need to set starting text position.
Arguments:
Optional bool as last argument specifies whether screen updates immediately with result. Default is true.
Before all of this text can happen, you need to load a font buffer for use. A good font to start with is NodeJS package oled-font-5x7.
Usage:
npm install oled-font-5x7
var font = require('oled-font-5x7');
// sets cursor to x = 1, y = 1
oled.setCursor(1, 1);
oled.writeString(font, 1, 'Cats and dogs are really cool animals, you know.', 1, true);
Checkout https://www.npmjs.com/package/oled-font-pack for all-in-one font package.
Sends the entire buffer in its current state to the oled display, effectively syncing the two. This method generally does not need to be called, unless you're messing around with the framebuffer manually before you're ready to sync with the display. It's also needed if you're choosing not to draw on the screen immediately with the built in methods.
Usage:
oled.update();
Draw a battery level in percentage indicator. This method allows for up to 4 different states of the battery:
Arguments:
usage:
// args: (x,y,percentage)
oled.battery(1,1,20);
Draw a bluetooth icon
usage:
//args: (x,y)
oled.bluetooth(1,1);
Draw a WiFi signal strength in percentage indicator. This method allows for up to 4 different signal strength of the WiFi signal:
Arguments:
usage:
// args: (x,y,percentage)
oled.wifi(1,1,20);
A wrapper for drawRGBAImage
that supports a fix animation. The animation always start from x=1
and y=1
.
Arguments:
animation = true
)animation=true
)resources
folderusage:
var font = require('oled-font-pack')
oled.image(1,1,'rpi-frambuesa.png',font.oled_5x7,true,false,false,true);
Author: hadifikri
Source Code: https://github.com/hadifikri/oled-rpi-i2c-bus
License: MIT