IR R3M0C0N 2v14J: Multi-Purpose Arduino Shield with IR
The assembled shield pictured above is a general purpose mixed bag of hardware for rapid prototyping on the Arduino. This shield features a variety of handy hardware as follows:
- Analog joystick (A0, A1) with center button (D4)
- Two momentary push buttons (D7, D8)
- Analog microphone and preamp (A2)
- Analog light sensor (A3)
- 5mm RGB LED on PWM pins (D5, D6, D9)
- Infrared Transmitter on PWM pin (D3)
- 38kHz infrared demodualtor/receiver (D2)
- Unused Arduino Pins (A4, A5, D10, D11, D12, D13)
- Reset disable slide switch for IR Bootloader
The schematic illustrates the circuit and connections to the Arduino as well as the color codes for the resistors (click for large image):
And the PCB layout:
Onward to the assembly:
When assembling a circuit board, start with the shortest components first.
This way, when the board is turned over to solder, the parts rest on the table and don’t fall out.
2. CERAMIC CAPACITORS
|All the ceramic capacitors are 0.1uF. The capacitor symbol on the circuit board looks like this, with incrementing numbers.
NOTE: C2 IS NOT A CERAMIC CAPACITOR & HAS A DIFFERENT FOOTPRINT.
|The 0.1uF ceramic capacitors are labeled ‘104’ which means 10 + 4 zeros pF. Sometimes they are yellow, sometimes they are blue.
(p = pico, u = micro, m = milli, n = nano)
|Carefully flip the board over. Solder each capacitor in place, and then trim off the extra bits.|
3. ELECTROLYTIC CAPACITOR
|There is only 1 electrolytic capacitor which is C2.
Note – The white stripe indicates negative.
|On the footprint, the white half circle marks the negative terminal. The shorter leg of the capacitor goes in the negative terminal.
Place C2, flip & solder, then trim the leads.
4. LIGHT SENSOR
|The light sensor is a light dependent variable resistor. This item has no polarity, ie. it doesn’t matter which pin goes in which hole. It looks like this.|
|The footprint symbol on the circuit board looks like this. Put it in, flip it over, solder and trim!|
|The transistor is a switch. This part is a BC548, a small signal NPN transistor. There are 2 of them in the circuit.|
|The shape of the body determines how it fits. Match the round and flat edges to the footprint on the circuit board. Place, flip, solder, trim.|
|The microphone is an electret type used to sense sense sound.|
|The footprint looks like this, with two offset pins that determine it’s fit. Place, flip, solder, trim.|
|This part is the slide switch to disable reset. It doesn’t matter which way it fits.|
|The footprint is at the bottom left and marked “RSTDSB->” and looks kinda like this. Place, flip, solder, trim.|
8. INFRARED LEDs
|There are two infrared LEDs on the circuit board. They are used to communicate with other IR shields or with a TV. LEDs are polarized, the long leg is positive. Inside the LED the anvil shape is typically negative. Sometimes the IR LED has a darker plastic body, sometimes it is clear.|
|The footprint looks like this and like the LED, has a flat edge to indicate negative. Place, flip, solder, trim.|
9. INFRARED DEMODULATOR
|This is the receiver for infrared remote signals, it contains some demodulation circuitry and a window filter around 38Khz. The part number is VS1838B.|
|The footprint is designed to accept different models. For this PCB occupy only the side nearest IR LEDs as indicated by the RED bar, which has the ground pin in the center (Also refer to the picture of the assembled shield at the top of the page). Place, flip, solder, trim.
SPECIAL NOTE: When soldering the demodulator, don’t dwell as too much heat can damage it.
10 RGB LED
|The RGB LED is common cathode, the negative pin is common. It has four leads that will need to be bent in alternating directions to fit the PCB.|
|It’s footprint looks like this. Be careful of the orientation, match up the flat side of the LED with the flat side of the PCB footprint. Also, the long lead is negative, it’s hole is marked with a square on the PCB. Place, flip, solder & trim.|
|The button is a simple 4 legged animal, it snaps in place any which way it fits. There are two of them, one with a blue hat and one with a red hat.|
|It’s footprint looks like this. Place, flip, solder & trim.|
|The joystick is a composite part containing two potentiometers, a button and some mechanical components.|
|It’s footprint looks like this. Make sure the pins are not bent going in. Place, flip, solder & trim.|
13. PIN HEADER
|There are four pieces of single row pin header, two pieces are 1×8 and the other two pieces are 1×6.|
|It’s footprint looks like this. Use the outside holes, closest to the edge of the PCB, the inside row is extra for hacking. Place, flip, solder, no need to trim.|
LIBRARIES & SKETCHES
|IR REMOTE LIBRARY||Ken Shirriff’s excellent Multi-Protocol Infrared Remote library for the Arduino|
|PinChangeInt LIBRARY||Library to setup buttons as Interrupts|
|BasicSketch||Starting point sketch with the pin names and setup.|