EP-0098

DockerPi NightLight

Description

DockerPi NightLight is a DockerPi series expansion board with 8 WS2812 RGB LEDs. The expansion board communicates with I2C protocol. It can be used in Raspberry Pi, Jetson Nano and other single board computers (require I2C peripherals).

You can programmatically control the color of each LED, such as Python or C, or you can control the color of each LED directly through system commands without programming. Most Linux distributions include the i2c-tools, which allows you to control this.

DockerPi NightLight can only be used one, but can be stacked with other DockerPi expansion board. If you need to run for a long time, we also recommend that you use our DockerPi expansion board to provide more power.

The module is stacked on the top layer and can be placed with acrylic decoration for better show.

Features

• DockerPi Series
• Programmable
• Control directly(without programming)
• WS2812 RGB LEDs
• Extend the GPIO Pins
• Recommended to be stacked at the top
• Can Stack with other Stack board
• Independent control of each LED
• 2 * Pre-make acrylic supports your quick start
• 2 * Blank acrylic supports your custom ideas
• Independent of the mainboard hardware (require I2C support)

Official Compatibility Test

Not only support the following development boards, other development boards can be compatible if they have I2C peripherals. (Note: some software changes may be required)

Platform	DockerPi Nightlight	Notes
Raspberry Pi All Model	√
Jetson Nano	√

Gallery

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Package Includes

• 1 x DockerPi NightLight
• 4 x M2.5x12 copper sticks
• 4 x M2.5x6 screws (Botton)
• 4 x M2.5x10 screws (Top)
• 1 x Acrylic Pattern Design (Stander)
• 4 x Acrylic Pattern Design (2x Caved and 2x blank)

How to use it

• Turn on the I2C interface

Open a terminal and Run sudo raspi-config
Use the down arrow to select 5 Interfacing Options.
Arrow down to P5 I2C .
Select yes when it asks you to enable I2C.
Also select yes if it asks about automatically loading the kernel module.
Use the right arrow to select the <Finish> button.
Select yes when it asks to reboot.

• Detect the register of the chip on board

i2cdetect -y 1
you will see this result:

• Lights up one LED

i2cset -y 1 0x15 0x01 0xff

 The first parameter "0x15" means the address of Nightlight hat.
"0x01" means the first LED's red color, every LED
has a register address, and you can follow this chart, "0xff" means give the LED 100% brightness
and "0x00" will turn of the LED, you can put the value from "0x00" to "0xff" to make a dim LED

Register Map

Register Number	Function	Value
0x01	LED1 Red	0(FULL OFF) - 255(FULL ON)
0x02	LED1 Green	0(FULL OFF) - 255(FULL ON)
0x03	LED1 Blue	0(FULL OFF) - 255(FULL ON)
0x04	LED2 Red	0(FULL OFF) - 255(FULL ON)
0x05	LED2 Green	0(FULL OFF) - 255(FULL ON)
0x06	LED3 Blue	0(FULL OFF) - 255(FULL ON)
0x07	LED3 Red	0(FULL OFF) - 255(FULL ON)
0x08	LED3 Green	0(FULL OFF) - 255(FULL ON)
0x09	LED3 Blue	0(FULL OFF) - 255(FULL ON)
0x0a	LED4 Red	0(FULL OFF) - 255(FULL ON)
0x0b	LED4 Green	0(FULL OFF) - 255(FULL ON)
0x0c	LED4 Blue	0(FULL OFF) - 255(FULL ON)
0x0d	LED5 Red	0(FULL OFF) - 255(FULL ON)
0x0e	LED5 Green	0(FULL OFF) - 255(FULL ON)
0x0f	LED5 Blue	0(FULL OFF) - 255(FULL ON)
0x10	LED6 Red	0(FULL OFF) - 255(FULL ON)
0x11	LED6 Green	0(FULL OFF) - 255(FULL ON)
0x12	LED6 Blue	0(FULL OFF) - 255(FULL ON)
0x13	LED7 Red	0(FULL OFF) - 255(FULL ON)
0x14	LED7 Green	0(FULL OFF) - 255(FULL ON)
0x15	LED7 Blue	0(FULL OFF) - 255(FULL ON)
0x16	LED8 Red	0(FULL OFF) - 255(FULL ON)
0x17	LED8 Green	0(FULL OFF) - 255(FULL ON)
0x18	LED8 Blue	0(FULL OFF) - 255(FULL ON)
0x19	Button	0x01 - Button Pressed 0x00 - Button Released

Example Demo(Raspberry Pi)

• Shell Script

The following script demonstrates turn on and turn off each LED.

#!/bin/bash

for i in $(seq 1 10)  
do
        i2cset -y 1 0x15 $i 0xFF   # turn on the led
        sleep 0.5
        i2cset -y 1 0x15 $i 0x00   # turn of the led
        sleep 0.5
done

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• C Language

The following code demonstrates the use of buttons and LEDs.

#include <stdio.h>
#include <wiringPi.h>
#include <wiringPiI2C.h>

#define BUTTON_REG_ADDR 0x19

int main(){
        int fd;
        int is_press = 1;
        int is_draw = 0;
        int i = 0;

        fd = wiringPiI2CSetup(0x15);

        for(i = 1;i<25;i++) wiringPiI2CWriteReg8(fd,i,0x00);

        for(;;)
        {
                if (wiringPiI2CReadReg8(fd, BUTTON_REG_ADDR) == 0x01 )
                {
                        is_press++;
                        is_draw = 1;
                        wiringPiI2CWriteReg8(fd,BUTTON_REG_ADDR, 0x0);
                }
                if(is_press && is_draw){
                        is_draw = 0;
                        for(i = 1;i<25;i++){
                                if(is_press > 3) is_press = 1;
                                if(((i + is_press) % 3) == 0)
                                {
                                        wiringPiI2CWriteReg8(fd,i,0xff);
                                }else{
                                        wiringPiI2CWriteReg8(fd,i,0x00);
                                }
                                delay(100);
                        }

                        wiringPiI2CWriteReg8(fd,BUTTON_REG_ADDR, 0x0);
                }
        }
}

Please note that the library is required for use:
gcc nightlight.c -lwiringPi -o nightlight

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• Python Script

The following code is recommended to be executed using Python 3 and install the smbus library:

import time as t
import smbus

DEVICE_BUS = 1
DEVICE_ADDR = 0x15
bus = smbus.SMBus(DEVICE_BUS)

while True:
    try:
        for i in range(1,25):
            bus.write_byte_data(DEVICE_ADDR, i, 0xFF)
            t.sleep(0.2)
            bus.write_byte_data(DEVICE_ADDR, i, 0x00)
            t.sleep(0.2) 
    except KeyboardInterrupt as e:
        print("Quit the Loop")

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Keywords

• nightlight, dockerpi, raspberry pi, light, i2c, smbus2, iot

Video Tutorial

• Please follow the link:
• [ DockerPi NightLight Board Tutorial| https://youtu.be/KI7cQQLffG0 ]