Sealed Tri-Color USB Controlled Hemisphere Alarm Light

Product ID: 5127
$79.95

Description

With this Sealed Tri-Color USB Controlled Hemisphere Alarm Light, you can easily monitor and alert humanoids as to the status of a project, machine, or even if the bathroom is occupied!

It's a lot like our other alarm light but this one doesn't come with a buzzer and in 'exchange' it has a sealed body which means it can be used in places with more dust and moisture. It doesn't have an official IP rating, but we think it's probably something like an IP65 (not including the USB connector which is not rated).

Unlike our "12V" style tower lights, no wiring or microcontroller programming is required. It's completely plug-and-play for use with any computer that has a USB port, even a Raspberry Pi SBC - so we recommend it when you just want to get something running and don't want to noodle around with 12V power plugs and transistors. 

The alarm light is powered and controlled over USB, so just plug it right in. Inside is a microcontroller connected over a CH43x USB-to-UART chip, so you'll need to install a CH43x driver for the COM/Serial port to show up.

Once the serial port is created, connect to it over 9600 baud and send command codes to turn on and off the LEDs. There's also a blink command, so you don't have to continuously turn on/off the LED to have a pulsing/blinking effect. See below for an example Python script that will toggle everything on/off to test.

Technical Details

  • Hemisphere diameter: 50mm

Python code example to control the lamp over USB:

"""
Example for Adafruit USB tower light w/alarm
don't forge to `pip install pyserial` or `pip3 install pyserial`
"""

import serial
import time

serialPort = 'COM57'  # Change to the serial/COM port of the tower light
#serialPort = '/dev/USBserial0'  # on mac/linux, it will be a /dev path
baudRate = 9600

RED_ON = 0x11
RED_OFF = 0x21
RED_BLINK = 0x41

YELLOW_ON= 0x12
YELLOW_OFF = 0x22
YELLOW_BLINK = 0x42

GREEN_ON = 0x14
GREEN_OFF = 0x24
GREEN_BLINK = 0x44

def sendCommand(serialport, cmd):
    serialport.write(bytes([cmd]))

if __name__ == '__main__':
    mSerial = serial.Serial(serialPort, baudRate)

    # Clean up any old state
    sendCommand(mSerial, RED_OFF)
    sendCommand(mSerial, YELLOW_OFF)
    sendCommand(mSerial, GREEN_OFF)

    # turn on each LED set in order
    sendCommand(mSerial, RED_ON)
    time.sleep(0.5)
    sendCommand(mSerial, RED_OFF)

    sendCommand(mSerial, YELLOW_ON)
    time.sleep(0.5)
    sendCommand(mSerial, YELLOW_OFF)

    sendCommand(mSerial, GREEN_ON)
    time.sleep(0.5)
    sendCommand(mSerial, GREEN_OFF)

    # Use the built-in blink modes
    sendCommand(mSerial, RED_BLINK)
    time.sleep(3)
    sendCommand(mSerial, RED_OFF)

    sendCommand(mSerial, YELLOW_BLINK)
    time.sleep(3)
    sendCommand(mSerial, YELLOW_OFF)

    sendCommand(mSerial, GREEN_BLINK)
    time.sleep(3)
    sendCommand(mSerial, GREEN_OFF)

    # Please be kind, re-wind!
    sendCommand(mSerial, RED_OFF)
    sendCommand(mSerial, YELLOW_OFF)
    sendCommand(mSerial, GREEN_OFF)
    mSerial.close()