Push Button Start

I think the timeout will be around 10 minutes, or until the drivers door is opened.  This will give people the ability to listen to the radio, without risking draining the battery.  After the 10 minute period a new 10 minute period can be started by simply removing the RFID tag from the antennas range and then bringing the tag back in to range.  This will allow poeple to simply listen to the radio, and perform other ACC tasks with the vehicle off.

peterubers, I missed your question about the RFID.  The RFID part is actually fairly simple, you can purchase RFID modules that are pretty much self contained readers.  You then interface them in to your project.  You can get them with digital or serial outputs, depending on your goals.  Then, you attach an antenna and learn the tags to the system and you are ready to go.  For this project, I plan to send a 1S signal every time a card is read (whether the car is read for 0.25S or 10,000S only one 1S signal is sent).  The RFID stuff is pretty cool!

KP --

I just drove a buddy's M35x that has the exact same Altima start/stop button.  I realized that you had to depress the brake in order to activate the starter -- i thought this was a very cool feature -- what are your thoughts?

The button looks the same, but it has some small differences (color and function).

I never thought about that, but it could be incorporated.

I was planning on setting it up so that you had to hold the button down for longer then just a 'push' to make it impossible to activate the system by accidently bumping the button.  Requiring the brake to be pushed down would only help eliminate that scenario.

are the LED's inside the button ring going to light up correctly to show acc, on, and lock?     and where are you going to mount this thing at?

as a side note...this is the stuff that dreams are made of,  it makes me wanna quit best buy and open a custom shop only doing crazy stuff like this all day.  it would be weird to actually use my brain instead of just sliding ford radios in and out or windsheild mount sat installs.

just kidding, we get to do some cool stuff there I just love the puzzle of getting one off systems like this to work and become a reality.

Yes, all the lights and functions will work just like OEM.  The controller is based around a 10mhz microprocessor.  I almost have the circuit board layout done that will control the button.

I believe, for now, I'm going to replace my cigarette lighter with the button.  They are very close in size, and my cigarette lighter would be the ideal place.

Keep in mind that usually there's a 2 second prime when the key is first turned to the 'on' position, and that the fuel pump runs during cranking.. so you could run into a situation where the pump is already running (but the engine is off) when you hit the button.

Try using a ground from one of the injectors; the ECM usually pulses the ground to fire the injector, and you could look for that pulse to determine 'start or stop'. Start would be switch closed without injector pulse, and stop would be injector pulse present and then switch closed. You could also use a trigger from a coil/coil pack.

I use Siemens PLCs.. bit of overkill for this situation, but it's nice having inputs and outputs and making stuff work by changing the software, isn't it?

Jim

The more I think about it, the less likely I'll even need an engine running signal.  I think I'm going to include it as an option, but at this point I think I'm going to build in a manual override to the on/off status of the system.  The button has an 'ON' LED that can be used to indicate to the driver the status that the system 'thinks' the car is in.  If the car is running, but the LED is off the driver can then quickly press and release the button and the state will change.  It would then require a longer press to start and stop the car (Pt >0.5 seconds for instance).

Once the digital input is set I have the ability to look for pulses or a constant signal - it's all in the programming.

My PLC background consists of AB and GE Fanuc 90-30s.  I've never had the opportunity to work with any Siemens stuff.  If you like PLC programming you should check out microcontrollers.  They offer quite a few advantages over PLCs - in size, price, and I/O flexibility.  The programming is a bit more difficult, as it is code based and not ladder logic, but it's pretty basic.

I 'stole' a microprocessor system from my little brother.. haven't had time to work with it yet.

Here's a description of one of the facilities I support..

There's a total of six buildings on the PLC network. Each building runs a GEM-80 PLC; five of the buildings are set up with control panels, and the sixth has a master control panel. No difference in the equipment, just configured differently. On the control panels, the PLC controls CCTV, Intercom, and door access. Four of the five control panels operate about 250 doors, 10 cameras, and around 20 intercom nodes.  The fifth control panel operates approximately 50 doors, 5 cameras, and maybe 30 intercom nodes. The master control panel has group control over each control panel (operate doors as a group), controls all cameras on each control panel, and selected intercom nodes on each control panel. From any control panel you can transfer control to the master control panel (which will also disable that control panel), or you can sieze control from any control panel using the master control panel.

The fire alarm system is also tied into the PLC system.. locally at each control panel the fire panel will signal the control panel information on where the fire is in the building; on the master control panel the resolution is limited to what building has a trouble or alarm on the fire panel system. The master control panel also monitors the fire panels in every building on the facility, regardless if they have  a PLC or not.

There's a bit of wiring involved.

I'd still encourage an 'engine running' signal on the microprocessor you're doing.. it'll help with anti-grind, and makes it better for the driver. Also continue to use the neutral safety circuit.

Regards..

Jim

Interesting stuff.  Our little facility has roughly 15 seperate machines utilizing different AB processors.  Some of the PLCs are about as old as me, and some of them are brand new, so it's interesting keeping them all working.  At the facility I work at we make paper caulking tubes (like the Liquid Nails people use to make speaker enclosures).  We're one of only two factories in the USA that make paper caulk tubes, so uptime is a very high priority.

I just finished the initial circuit board layout.  I included some flexibility on the running input.  I included space to make an optically isolated tach reading or a simple transistorized digital input.  Keep in mind, that in this revision the start button won't actually start the vehicle automatically - I'll have to hold the button down to crank.  In the next stage a simple push of the button (after RFID permission is granted) will completely start the vehicle using a programmable tach signal.

What kind of microprossor did you steal?  I'm a big fan of the Atmel AVR series.  They are cheap, reliable, powerful, and readily accessible.

It's been a while, but I've made a little progress.  I've got a pushbutton start system installed in my 1995 Eagle Talon.  This is the 'test' car before it goes in my '04 G35 twin turbod coupe.

Before:

After:

Hide away control module:

All and all it works pretty good.  There are 2 or 3 bugs in the firmware that need to be ironed out, but I have acomplished the first part of my goal.  The next step is to integrate the RFID portion in the security and adapt the module to act more like a 'remote start' then a 'relay controlled by a pushbutton'.