User Manual
All the terminals are low active. When the Raspberry Pi outputs Low Level from its IO, the LED related to
the corresponding channel lights up. At the same time, the relay NO ﴾normally open contacts﴿ close and the
NC ﴾normally close contacts﴿ open, so as to change the ON/OFF status of the external circuit.
﴾PS: Remember to connect the jumper Relay_JMP!﴿
Before the relay action: After the relay action:
Sample programs
The sample programs of this board include Shell, bcm2835, WiringPi, python and Webiopi.
Development environment
Before using this expansion board, you should install some libraries to Raspberry Pi, such as bcm2835,
wiringPi and python. For more information about the installation and configuration of the RPi library
functions, please refer to Libraries Installation for RPi.
When finished the configurations above, you need to download the sample programs, and then copy and
extract them to the system. For example, input the line
tar‐zxvfRPi_Relay_Board.tar.gz~
to extract the downloaded program to the directory of /home/pi. Some of the sample programs can be
implemented via different ways, such as the libraries of bcm2835, wiringPi, sysfs, python and so on. That
means you can implement a same function by using different libraries. Therefore, the libraries of bcm2835,
wiringPi, python and Webiopi should be installed to the RPi before used. If the sample programs presented
in the next section are unable to be performed after installing the libraries, you can try to apply the
command
