So I want to start a car- Explain to me like i'm five
Lol, my bad.
Arduino Uno is the basic full sized board, you can pick them up on eBay easily enough. They run an atmega328p and have a 'standard' amount of IO pins.
The Arduino Mega 2560 runs a more capable atmega chip, with more memory for program space and more IO pins.
They will both run the same Arduino code, with some allowances for pin out differences.
I like to start with a Mega with the capability of putting everything if can think of onto it, then condense things down until it's a little more efficient. That way you can then see if you're able to shift your prototype down to a less costly Uno unit or maybe even a Pro Mini or Nano. Both of those are cheap, and small enough to incorporate into a prototype breadboard or basic circuit.
Ah Okay thank you for explaining that! Makes total sense now. This will definitely help me out. I think I'll do the same as you and just start out with the Mega.
LoganFive last edited by
A good suggestion, and perhaps Lokki has also done this, is to use and become familiar with the software Fritzing. http://fritzing.org/home/
It's free software(That appreciates donation) for planning and prototyping arduino circuits and breadboard/protoboards in you computer to test. It has lots of help and a community willing to help and share projects. You can even order a custom fabbed PCB board for your project.
Yup. I use fritzing sometimes when I'm not using Eagle... but I have a bad habit of letting everything happen organically and then trying to diagram it afterwards.
Hey all newbie here so please keep up the great work at being patient,,,so I'm in the same boat as the op. However I think he had even more experience than I have.....if we have any Australians around would it be possible to get their advice on where to source.... I get the feeling maybe Loki is a oz boy?
I'm hoping that with advice I can get this done and maybe put a nice wiki or step by step as to how it's done for all of those like me who really struggle.....
So I guess first things first....where should I start....I'm ordering my ring on Monday and I would like to have the basics up and running for when it arrives.
I understand the basic circuit but not the arduino bit....is it a chip or a whole board?does it have a USB port of something like that?
Thanks to all who get back to me in advance
@MarkGabb G'day. 'Straya! lol
What state you in mate? I float between SA and Victoria at the moment, if you're somewhere around or in between we might be able to catch up or whatever.
I think if you've got absolutely zero experience in electronics or whatnot you might be best off seeing if @MrStein is selling his car starter boards yet. They're a bloody nice design and should be basically adaptable for anything you can think of - with a couple of caveats. You must, must be aware that going full NFC start will require removal or modification of an existing mechanical steering lock.
This is going to be true of any change in the starting circuit really, you'll either need to retain the key for steering unlock (or vehicle activation in newer models) or mod the hell out of it.
Anywho, if you've got a bit more knowledge I believe he has the files up here somewhere for download, he's done a version that takes a whole Arduino Nano (which has a USB port for programming) and he's also working on a version which uses only the chip, which is a bit more involved for programming but isn't insurmountable.
Loki. I'm a gippslander down in victoria
Well I guess you could put it this way. I did electronics in school so I know the basics of soldering and electronics and can work from a diagram.
I'm a IT admin so I should be able to work with anything that has a USB port
It will just be connecting the dots that will involve the effort
If anyone is able to point me to the spec diagrams that would be great, I can check them out and see how I go....
I guess I just ned to make sure that for future use, it's also capable of handling a second io to run the doors, as it seems to make sense to me to have it run al off one controller
And I suppose the other the I need to do is understand what all this stuff is about public and private keys
@lokki cheers for the upvote.... so basically from my own research I think I just need to get the parts.... which means I need to play with a design.... hunting though the forums now to find a basic design of the board to start with
Hi @MarkGabb - sorry I didn't do more than that, I got distracted mid answer.
My thread really doesn't have much design info, but you can see from the way the sketch is written which outputs are being used to do what, and then from there you can add transistor/resistor/relay etc to get it working. It's all pretty basic really, and I may be goaded into doing some kind of drawing. I've been slack about that.
@lokki. Cheers...I guess ill just have to look up what parts I need and start it from there....I'm seeing alot of disagreement on which type of chip and reader to use... any sugestion
If you're building yourself and you want a usb port to program (it really is easier that way) then just ebay an arduino nano and grab an elechouse PN532 V3 reader. YMMV but that should do the trick for you.
@lokki Awesome. Ymmv?
Your Mileage May Vary. ;-)
Cheers man. Your a great shops. I'll do up my shopping list tomorrow and start my notes. If I start uploading diagrams can you look them over and make sure I've got it right?
Yeah no worries @MarkGabb. Just tag me in the post to make sure I see.
**updated to include ignition barrel part so i know its right
***ok so upon further reading i cant just use any pin i want on the arduino nano, and i have to use specific points...which ones thoug is a bit harder
****after looking at @lokki pictures of his boards again im realizing that i really have no idea what im getting myself into, but perserverence is the key i think
I see what you mean with the pictures, I attempted to edit them in but google drive seems a bit retarded like that. I use imgur, it works well for me.
So first, just to reassure you, the circuits I hacked together are actually really simple. They just look 'difficult' because they were less planned than they were evolved. I changed my mind several times in the process and instead of starting again just rerouted things, added parts and links to join everything together.
So don't be too put off by that!
If I do it again, and I have no doubt I will, I will do it differently.
Now, pin assignments on arduino can be mixed and matched within certain basic limits. The most important concern I find is that you keep the I2C pins and any other hard wired communication points free as long as possible. You use those ones last and only if you run out of pins for other things.
You'll want the I2C pins for your NFC reader board. I2C also allows multiple items to be stacked on the same port BUT only if they have different addresses.
This means that you may have a V3 reader and another I2C device connected to the same port but you may not have two (2) V3 readers conncted to that point at once.
You may have the two readers on the same data lines but only activated one at a time, or you may have the same readers on different ports (I2C and SPI) at the same time.
My approach to this has been to add an extra header for a second board for door access... but I'm not using it until I'm happy with the way the rest of the unit works. At that point I will add circuitry that allows the 'door lock reader' to be active when the car is locked and off, and inactive for a time after the door is unlocked then closed - allowing the 'ignition reader' to become active and start the car.
But don't worry about any of that yet, concentrate on the starter part of your project and you'll be fine.
Your drawing of the ignition barrel is pretty much it in a nutshell - in my skyline though, I have an extra wire that powers the computer and instrumentation, the car runs without it in a basic mode but it does need to be linked in. You may want to check a gregorys manual or similar and have a look at the circuit diagram for your ignition barrel.
What car are you hacking on?
Something I'm noticing on your diagram is that you'll want to add something in between the relay and the arduino to trigger them properly without cooking the arduino - max current rating is really low and running multiple relays straight off the board will end in tears. just add transistor and resistor in between so that it's the transistor triggering the relay when the arduino single pin is active high, (the resistor is for pulldown) and use a flyback diode to stop the relay 'bouncing'.
Duplicate that for all your relays and you'll be right!
Just out of curiousity, what's the go with the reader units in the picture? I'm having crazy issues seeing them properly so talk me through what they are and why they are where they are. :-)
@Lokki the Readers were just any reader i could grab out of fritzing...didnt seem to be anytnhing applicable.....
im having on a mitsbishi mirage 96 model, so no computers.....i figure it makes it easier to start with...and lots of wrecker parts is a screw the barrel or anything like that....
i find drawing out the diagrams to be difficult as you have to try to keep everything easy to read, and i dont remember much of my electronics.....
so on the Active side of my relay as a transistor, resistor, and a "flyback" diode on the other side?
as i dont have central locking in my car yet, ill leave out the second reader....and look at adding it in later to make it simpler....
ill upload a new design either tonight or tomorrow...will be great if i get this all done, ill have a great FAQ and instruction manual for anyone else who wants to follow the steps
**i dont see i2c ports on the diagram of the arduino i have?
@MarkGabb I'm just downloading fritzing and I'll see if I can knock out a small diagram before I get distracted.
Car sounds good, it'll still have a computer so you'll want to double check what goes active on the back of the ignition barrel when you go from OFF to ACC to ON.
I2C is basically GND, PWR, SCL, SDA - the important ones are SDA and SCL. You'll need to keep those ones free for your reader board.