IO board is the acronym for input/output board. As the name hints, the IO board can be configured into input or output modes by turning the corresponding switches on and off. During the input mode, the push buttons can be used as inputs.
There are 8 switches which can be connected to a port using the given connector. In output mode, the state is displayed by 8 LEDs which corresponds to a port. There are two IO boards in PIC kits which will give 16 IO pins as a whole.


There are two I/O boards, each have user configurable input and output ports. A user can choose input or output functions by using the tactile switch. During the input function, the push button can be used to give inputs and during the output function, LEDs indicate the output status.

I/O board is an input/output device shipped with OpenLab. Input and output devices and its functionality can be changed with toggle buttons. OpenLab consists of two I/O boards. One on the bottom left corner and the other on the bottom right corner. Both the I/O boards are eight-bit devices which contain 8 LEDs and 8 switches. The left I/O board is controlled by port D by default and the right I/O board is controlled by port B by default.



Tactile Switches

They help to select input and output functions. Each bit has a corresponding switch.

Push Buttons

When the tactile switch is in the input mode, a user can use a corresponding push button for giving inputs.


The LEDs indicate output status when the tactile switch is in the output mode.

The above image shows the basic structure of I/O board. I/O board can be activated by turning on the switch on the
top left side.Push buttons act as data input device and LEDs act as output displaying device. Toggle switches are used to toggle between the input mode and output mode. Test pins are used for debugging purposes. The I/O board provides onboard 5V supply.

Connecting the Board

The board can be powered by turning on the switch SW1. To establish the port connection, connect the J5 to the nearest baseboard port J21. Connect the I/O board to port D using FRC cable.Toggling the switch in backward direction makes I/O board in input mode.Toggling the switch in forwarding direction makes I/O board in output mode.


IO board contains 8 toggle switches in which each controls one bit of the port. Putting the toggle switch in input position will make the corresponding bit in input mode. Likewise, the output mode will make it in output mode.

Each bit of data can be entered by pressing the corresponding button and turning off the LED indicates the button press in the input mode.


Move the switch to the input position, now the pin will be configured as input and port pins can be set and reset using the push button. If the switch position is output, LED will show the status of a port pin. If the port pin is high, LED will glow and if the port pin is low, LED will be OFF.

Input Mode

Put the switch lever (SPDT) in down position. Now use the push button below the switch to set and reset the pin.
The default state is high and pressing the button will give a ground signal (low) on the pin.

Output Mode

Put the switch lever (SPDT) in up position. Now the output will get displayed on the LED.

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