Hard to explain project for title line :)

I just bought an arduino and a basic kit and have been messing around with it. I’m really new to all this stuff, I’m technically minded but new to circuitry, microcontrollers and this code. I had an idea and wanted to build it so I bough this stuff and figured I’d start somewhere. I want to make a prototype and have it working decently by November 14th.

I need your help making my idea :slight_smile:

How it would work:

Basicly a button is pressed that turns on blinking lights, at the same time it continuously sends out a wireless signal. The signal is then received from a second device and a light turns on, a buzzer sounds once and a message is displayed on a basic led display.

extra bits: if the button is pressed again it stops the lights and the out going message. The message is saved on the second device and not actually broadcasted. The wireless signal is just to tripper the action. The second device should display the message, light the light until the wireless signal is gone.


  • device one:

  • Arduino
    4 led lights
    wireless sensor

Device two:

  • Arduino
    wireless sensor

Would this work for the wireless transmitter and receiver?

Would this work for the Display?

I already have lights, a buzzer and buttons as well as one Arduino uno

Will need a lot of help hooking int all up, writing the code and testing it.

Any book suggestions or webpage projects to help my skills (especially if related to this projects)

Thank you all in advance!

I'm not sure you need that sensor/wireless bundle. It looks like one end is meant to operate standalone and transmit data from sensors. You just need a 433MHz transmitter and a receiver - I think they will be cheaper. This Thread may be helpful Planning and Implementing a Program ...R

The link is not working for me.

mattmers: The link is not working for me.

Sorry - I haven't got used to the new Forum system.

I've corrected it and I hope it is working now.


"Basicly a button is pressed that turns on blinking lights, at the same time it continuously sends out a wireless signal. The signal is then received from a second device and a light turns on, a buzzer sounds once and a message is displayed on a basic led display." 1) So a button is pressed and turns on blinking lights - any Arduino can do that. 2) It continuously sends out a wireless signal, is this over wifi? If so the Yun is probably the easiest place to start. 3) The signal is received by a second device - again the Yun should probably be the board of choice for the second device as well. 3.5) You may want to look into socket programming, since your sending a signal over a network. Temboo has some libraries that could simplify that. 4) Lights sounds and buzzers, all output.

It sounds to me like broken down into steps you are: Blinking arduino 1 and sending a signal over the network, than blinking arduino 2 when the signal is received turning on lights, buzzer and a message. Basically, arduino to arduino text messaging. Some starting points: LEDS: https://id.arduino.cc/auth/login/?go=1%26returnurl%3Dhttp%3A%2F%2Farduino.cc%2Fen%2FTutorial%2FBlink%3Ffrom%3DTutorial.BlinkingLED Sensors: http://www.devfactor.net/2014/10/20/sensors-actuators-circuits/ Network: https://www.temboo.com/ Board: http://arduino.cc/en/Main/ArduinoBoardYun?from=Products.ArduinoYUN

it is not exactly arduino to arduino text message. The message will always be the same. The second arduino is basicly just telling you the other one is around.

Thanks so far guys, i have some readng for the next couple days :)

What do you guys think of these?

Transmitter: https://www.sparkfun.com/products/10535

Receiver: https://www.sparkfun.com/products/10533

Display: https://www.sparkfun.com/products/709 Would the display be able to hook up to the Arduino uno if it needs ~11 ports or would I need to buy a Arduino Due?

I should have everything I need to design and build it after all that... I think.

Those RF modules should be OK.

If you need more pins a Mega is probably a better step up from an Uno.

I think you can get LCD modules that use I2C and would only need 2 or 3 pins. You can also use a shift register to give an UNO access to more pins. That is probably the cheapest option but it may be that bit more complicated.


I found a display that includes a serial backpack and I think it does not require the ~11 ports. https://www.sparkfun.com/products/9067

That module looks ok, it will only use 2 pins, either Tx and Rx from a hardware UART or any 2 pins is using SoftwareSerial.


mattmers: I found a display that includes a serial backpack and I think it does not require the ~11 ports. https://www.sparkfun.com/products/9067

The Sparkfun page says that is a 3.3v device so you will need to reduce the 5v that the Arduino produces using a voltage divider or something similar. The Arduino should have no problem working with 3.3v as an input (if the device has any output).


My arduino also has a 3.3v output. Once I get these, how should I start? Should I try to figure out how the circuitry should be physically designed first?

A 3.3V output won’t solve signal from 5V pins burning the 3.3V device pins.

The usual solution at low currents is to make a voltage divider per 5V to 3.3V pin.

Here’s a page you’ll want to bookmark. It has multiple methods.

You don’t need to level where the 3.3V is doing the signalling, like Arduino 5V MISO to SD or ground.

Guess I’ll figure that out in due course. Bought the other arduino today. Will be ordering the lcd, transmitter and receiver tonight. That means I will have all the parts soon, Then I get to figure out how to build this thing. I have also recruited a friend who has some more experience than me.

Ok, ordered the parts which will take between 5-10 days to get here. I also bought my ticket for the upcoming even I'm going to on the 14th, 15th, and 16th. Some can probably guess what it is. Hope I can get this done before the 14th. Wish me luck

You will have the voltage leveling covered? Radio Shack does have emergency parts mostly at emergency room prices.

I lived in one town that had an electronics distributor close by. But then I didn't know just how good I had it.

I new to this all and I'm not exactly sure about what your talking about I understand action needs to be taken to power the display. Also the link provided is for raspberry pie, what is the gpio on a arduino? I have a radio shack so I figured if there were any emergency parts I'd go there. Thanks for walking me through all this guys.

This is why I say try and make the whole plan before you buy parts or write code. How can you plan with so much unknown?

But money spilled will provide a good lesson and next time you will have the wisdom. Don't worry, you should get through this... I learned many lessons the same way and worse! Still do at times.

If I want to solder from my 5V UNO to a 3.3V micro-SD card adapter sleeve to use micro-SD cards, I have to make sure that the Arduino 5V signals to not go direct to the SD or SD will burn up.

I can POWER the SD with the 3.3V from the UNO but the Arduino SIGNAL lines are 5V.

The Pi page is relevant because the Pi is 3.3V and Arduino is 5V. What is required for the Pi is also required for the 3.3V SD.

GPIO is General Purpose Input/Output. All the Arduino I/O pins can be used for that.

SD runs on SPI Bus. That has pins for; SCK or CLK, Clock, the pulse from the controller that makes the communication stay in step; MOSI, Master Out Slave IN communication 1 bit per Clock tick; MISO, Master In Slave Out that carries 1 bit back to the controller at the same time, 2-way data on the same Clock tick; and SS, Slave Select that tells the slave (this time SD) to run.

There is also Power and Ground but the signals are MOSI, MISO. SCK and SS of which the Arduino is the sender, the one providing 5V for all except MISO the Salve Output line.

Those Arduino-powered signals, the 5V on HIGH, those must be made 3.3V for the SD pins. And that can be done with a voltage divider for each one, two resistors and a wire to ground each.

Even if your device is not a Pi or an SD, if it is a 3.3V device then it needs this protection.

Do you have a multimeter? If you do then you can test such a circuit before connecting. It is a tool you should have. You can pay a lot at a store or less than half online but you need to get one and learn the basic use. Google is your friend to find those lessons with pictures and explanations.

I think I gave you enough for now. there is more but until you learn this much it will make poor sense. So take this step in learning as part of the way to get to your goal.

I've been wrapping my head around what you said the last 2 days. I think I understand what your saying and Just have a few more questions. The serialLCD uses 3 cables; 3.3V, Ground and Rx. Would all 3 require voltage regulators or just RX and 3.3V? Also does this guy have it hooked up poorly then?


What do you think of this video? https://www.youtube.com/watch?v=hAB_X5EBtyU

Oh, searched my house for multimeter, found its box and cables but no clue where it is at. I'll be getting a new one soon.

Take care how you power it especially if you are using other shields, boards or anything that uses more than a little current. You don't want the Arduino to have more than 200mA running through it and that is the upper limit. But just the LCD may not be a problem.

For signal to your LCD, only the LCD RX line needs leveling. That is all except for the how.

I like the diode and pullup solution because it is simple, few parts but I think less power waste than the 2 resistor divider. Serial is voltage HIGH for 0 bits and the resting state, LOW for 1 bits. that's just the opposite of what you might expect. Reason is that if the resting state was 0V the line would "float" as outside EM induced power into the line. A line held HIGH is harder to influence. Most, almost all of the time that serial line will not be sending signal. Holding a line HIGH through a voltage divider means a small constant drain where the diode and pullup means far less drain (nothing is ever 100% efficient, thermodynamics is real). You build what you're used to so get used to the lesser drain that is still easy and if/when you go to batteries or other off-grid, your designs will be more fitting.

You will see more of that kind of choice as you get more experience. If you see regulators or buck converters, read enough to know the pros and cons and how to find the information again of you're not ready for the whole course.

For the meter, do some shopping and ask questions in the electronics or Bar Sport part of the foum and you will get professional advice and probably a few links to learning sites.