Shields

Arduino Shields - On top of your Arduino, shields are pieces of hardware that sit often to give it a specific purpose.  A shield can initiate a bit of hardware. To make an application easier based on demand from the Arduino community these shiels can be used.  As they are sold pre assembled or as kits, these shields can be simple or complex.to assemble the Arduino shield as you need it to be,  these kits allow you more freedom. To assemble the circuitry of the boards, some kits require your effort although more complex shields may already be largely assembled, needing only header pins.

For more than one purpose, shields enable you to use your Arduino and to change that purpose easily. Watch out for those that need to use the same pins, if you stack shields. By your Arduino and another device, any communication needs a common GND.

Arduino shield combinations

As shields can be stacked on top of each other forever, there are some points that you should take into consideration before combining them:

Physical size:  Components that are higher than the header sockets may touch the underside of any board on top of it. There are few shields that just don’t fit on top of one another. if a connection is made this situation, can cause short circuits that shouldn’t be, can seriously damage your boards.

Obstruction of inputs and outputs: By another shield, if an input or output is obstructed it becomes redundant. There’s no point in having a joystick shield or an LCD shield under another shield because no more than one can be used.

Power requirements: A lot of power is required for some hardware.  To use the same power and ground pins, it is all right for shields there is a limit to the amount of current that can flow through the other input/output (I/O) pins: 40mA per pin and 200mA max between all I/O pins. More this will increase the risk of seriously damaging your board and any other attached shield. By powering your Arduino and shields from an external power supply, you can easily remedy this problem, as that the current isn’t passed through the Arduino. If you’re communicating between a board using I2C, SPI, or serial make sure to use a common GND. 

Pins: Always ensure that shields aren’t doubling up on the same pins. as some shields require the use of certain pins. The hardware will just be confused; in the best case, in the worst case, you can send voltage to the wrong place and damage your board.

Software: To work, these shields need specific librarie. There can be conflicts in libraries, calling on the same functions so make sure to read up on what’s required for your shield.

Interruption with radio/Wi-Fi/GPS/GSM: To get a clear signal, move antennas or aerials away from the board. , it’s generally a bad idea to cover it, if an antenna is mounted on the board,  at the top of the stack, always try to place wireless shields.

Final Thought

Mentioned above is the information about Arduino shields, you can check out the details of how shields perform their desired task of protecting the boards above.