
Grove – Relay User Manual
Version: 1.0
Release date: 2015/9/22
Wiki: http://www.seeedstudio.com/wiki/Grove_-_Relay
Bazaar: http://www.seeedstudio.com/depot/Grove-Relay-p-769.html?cPath=39_42

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Document Revision History

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Contents
Document Revision History ········································································· 2
1. Introduction ······················································································· 2
2. Specifications ····················································································· 3
3. Usage ······························································································ 4
3.1 With TI LaunchPad ················································································· 4
3.2 With Arduino ························································································ 5
3.3 With Raspberry Pi ·················································································· 5
4. Resources ·························································································· 7

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Disclaimer
For physical injuries and possessions loss caused by those reasons which are not related to
product quality, such as operating without following manual guide, natural disasters or force
majeure, we take no responsibility for that.
Under the supervision of Seeed Technology Inc., this manual has been compiled and published
which covered the latest product description and specification. The content of this manual is
subject to change without notice.
Copyright
The design of this product (including software) and its accessories is under tutelage of laws. Any
action to violate relevant right of our product will be penalized through law. Please consciously
observe relevant local laws in the use of this product.

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1. Introduction
The Grove-Relay module is a digital normally-open switch. Through it, you can control circuit of
high voltage with low voltage, say 5V on the controller. There is an indicator LED on the board,
which will light up when the controlled terminals get closed.

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3. Usage
3.1 With TI LaunchPad
This example showcases how to use the Grove-relay module to control larger load, i.e. a desk
lamp light. A 3V voltage signal can cause the relay to switch on, allowing current to flow through
the connected appliance.
/*
Relay
The basic Energia example.
This example code is in the public domain.
*/
#define RELAY_PIN 39
// the setup routine runs once when you press reset:
void setup() {
pinMode(RELAY_PIN, OUTPUT); // initialize the digital pin as an output.
}
// the loop routine runs over and over again forever:
void loop() {
digitalWrite(RELAY_PIN, HIGH); // turn the relay on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(RELAY_PIN, LOW); // turn the relay o by making the voltage LOW
delay(1000); // wait for a second
}

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3.2 With Arduino
Below is a demo that shows you how to control a Grove - Relay with a Grove - Button. When the
button gets pressed, the relay will close.
// Project Five - Relay Control
//
void setup()
{
pinMode(1, INPUT);
pinMode(2, INPUT);
pinMode(6, OUTPUT);
}
void loop()
{
if (digitalRead(1)==HIGH)
{
digitalWrite(6, HIGH);
delay(100);
}
if (digitalRead(2)==HIGH)
{
digitalWrite(6, LOW);
}
}
3.3 With Raspberry Pi
This sample is show you how to use Grove - Relay by Raspberry Pi. The demo below will show
that the relay be control by Grove -Button.

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# Raspberry Pi + Grove Switch + Grove Relay
import time
import grovepi
# Connect the Grove Switch to digital port D3
# SIG,NC,VCC,GND
switch = 3
# Connect the Grove Relay to digital port D4
# SIG,NC,VCC,GND
relay = 4
grovepi.pinMode(switch,"INPUT")
grovepi.pinMode(relay,"OUTPUT")
while True:
try:
if grovepi.digitalRead(switch):
grovepi.digitalWrite(relay,1)
else:
grovepi.digitalWrite(relay,0)
time.sleep(.05)
except KeyboardInterrupt:
grovepi.digitalWrite(relay,0)
break
except IOError:
print "Error"
Run the program
Find the path to the file(According to your own path)
cd GrovePi/Software/Python/
Run Program
sudo python grove_switch_relay.py

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4. Resources
Grove - Relay Eagle File
Relay_Datasheet
how to upload code
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