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Indicator 'Buttons'
Rob Lane - 22/5/03 at 08:44 AM

Theres a thread on Blatchat at the moment where some of the guys are wanting to add a pair of pushbuttons to the steering wheel to operate the indicators instead of the horrible switch on Caterhams.
Set me thinking that this is an easy add on for a Pic micro, either as standalone or as part of dash system.
I know there's a couple of you doing these (Dave Jenkins?) and wondered if you had considered this.
A small ali plate is made up to mount behind wheel with a curly cord and on the plate is two pushbuttons, press right to turn right, and it self times out or will cancel with a further press of button. Sounds a neat system.

I'm looking at doing some mods to my car along these lines and I've also discussed with Dean C regarding doing away with the ignition key and switch and making the car remote control starting using a two button remote. That will puzzle any thief who would try to steal it!
I already have radio control receiver unit with handsets as it's something my son is doing for the Max Power types to remotely switch on their undercar neons.

Any thoughts?

Rob Lane


David Jenkins - 22/5/03 at 09:08 AM

I must admit to wimping out of using PICs in my car, due to concerns about their sensitivity to electrical interference. The problem isn't insurmountable, but it would take time and effort - for me, I'd rather put more time and effort into building the car! Because of this I bought ordinary instruments.

However, I have used one PIC, for my immobiliser - but that doesn't have to do anything when the engine is running, as I've used a relay to lock the system enabled once the PIC says it's OK.

I've gone for simplicity and used a mechanical switch for my indicators, but I've gone to a lot of trouble to integrate it into the dashboard/steering column cowling.

Sorry to be negative, but in my experience PIC circuits either work perfectly, or they're an absolute bar-steward!

cheers,

David


stephen_gusterson - 22/5/03 at 09:11 AM

If you dont want the 'timeout' feature, I would have thought that you could do a 'push to indicate, push again to cancel' feature for both sides with a couple relays.

A simple relay system could also be used for the 'start' button. It doesnt necessarily need a processor. It wouldn be remote tho.

atb

steve


stephen_gusterson - 22/5/03 at 09:13 AM

i agree with David - making a pic project work in the electrical noise experienced in a car isnt always easy......same for any cpu

atb

steve


ceebmoj - 22/5/03 at 10:06 AM

Hi all though you could use a PIC it would be a bit of over kill in my opinion to use it for this application. I know it is not the same car but this guy has a hard-wired solution on his ultima. Cery nice car as well cant rember exactly where on the site it is but if you look through the build diary there are a lot of details


http://www.ultima-gtr.info/index.htm

PS probably what I would build if I had loads of money


Rob Lane - 22/5/03 at 10:08 AM

They'll work alright, put unit in diecast box, just add an RF choke in volts feed line and feedthrough decoupling capacitors when shielded wires exit box.
Ground shield one end only, at box.
(Johnny Birketts at Lincoln did decoupling feedthroughs)

I used serial lcd and did same as above on two data wires to display and it stayed stable.

Must admit, up to doing the RF techniques as above it was a real pig to keep from locking up.

Regarding the starting bit. That wasn't to do with the Pic but a remote starting feature using radio remote control.

Think of it this way: NO visible means of starting car! NO pushbutton, key or anything!
You turn up with two button remote in pocket, press one button, ignition on, press momentary second button, engine turns over and starts.
Place remote control handset onto piece of velcro on dash or tunnel. Drive off.
When wanting to stop. Press 'ignition' button on remote, engine stops. Place remote in pocket and leave car!

Maybe a toy, but what a way to immobilise car! Provided of course you hide all this and use techniques to disguise wiring from thieves.
Mine's fairly easy as it's ECU and electronic based, perhaps a bit of a no no for a standard ignition Xflow. NO amount of fiddling will stop anyone stealing those, far to easy. Easier to remove rotor arm or have removeable steering wheel!

Incidently, I've heard of three genuine thefts of Locosts and none have been recovered !!!


Rob Lane - 22/5/03 at 10:15 AM

I posted the Pic bit mostly for the guys who were building other systems. It was meant really as a software-ish add on to their system.

Pics are cheap, although it may seem overkill theres potential left for expansion and a rewrite of software when other ideas crop up. I suggested intermittent wiper control for Caterhams as they don't have that.

How are you guys doing who are using Pics? Davids replied but wasn't there a couple of others.


Simon - 22/5/03 at 11:15 AM

Chaps,

I have no idea what "pics" etc are, but on BMW M/c's a pushbutton is used.

One on each side of the handlebars (for left and right !) and under the right button is a cancel button.

They also self cancel after about 5 secs.

Might be worth thinking about, as it's a ready made system.

ATB

Simon


ceebmoj - 22/5/03 at 11:21 AM

Hi

I have a couple of PIC projects on the go at the moment

1.)Digital dash
2.)Rpm leds like f1 steering weal
3)Bike push button gear change

1 incorporates 2 but I found a number of people who jus wanted 1

3 just got fiddling with some code (I now sound really sad) and it ended up as 3 then mentioned it in hear and found there was a lot of interest.

I am shielding as you described and have a chock I have found a good was to get encloses that are suitable is to get hold of ECU boxes form scrap yards and mount every thing up in them they also have the sockets built in already making it an easy neat solution.


Microchip mack a device that is aimed at radio aplications if you go to ther site you can oder a free sample

[Edited on 22/5/03 by ceebmoj]


ceebmoj - 22/5/03 at 11:23 AM

PIC

Programmable Integrated Controller

It is all most every thing you need on a single chip to tackle most hobby electronics problems up to some reasonably complex stuff


stephen_gusterson - 22/5/03 at 02:06 PM

Ceeb.

I read an article once that said the PIC meands Programmable Interrupt Controller.

The first device was an interrupt controller made for a company that didnt use it. The technology was then spun off by microchip to make a controller for general use.


Rob.

One possibly better way is to use an RFID device

also done by microchip. - look at their site.

You 'touch' a fob against a sensor, and it recognises a code from the fob. summat similar is used on pub tills to ID the operator - you might have sen them touch something to the till.

I recon this is similar to the system renault use - a proximity 'key card' and a start button.

On the renauly, you have to depress clutch to start.

Imagine leaving in gear and pressing the remote........


atb

steve


David Jenkins - 22/5/03 at 02:17 PM

quote:
Originally posted by stephen_gusterson
You 'touch' a fob against a sensor, and it recognises a code from the fob. summat similar is used on pub tills to ID the operator - you might have sen them touch something to the till.


Steve,

This is pretty much the technology I'm using for my immobiliser.

It's a thing called an iButton made by Dallas Semiconductor. It's a stainless steel thing that looks like a camera battery. It contains a chip that has a unique 64-bit id code with a few billion permutations. The code is accessed using a protocol called 1-wire, which is very difficult to set up without libraries, etc. (timing's a bit critical). The language I use (JAL) has these libraries available.

For further info, do a Google on iButton. I got some as free samples but even if you have to pay they're seriously cheap.

cheers,

David


ceebmoj - 22/5/03 at 02:56 PM

The ibutton is good I have used it for a couple of security systems and it has the added bonus of being practical indestructible for every day use. The are also a number of 1-wire libraries out there for free as Dallas Semiconductor also supply some instruments in this format. I stand corrected on the definition of PIC


Northy - 22/5/03 at 09:06 PM

I think you'll find that PIC stands for:

Peripheral Interface Controller

Regards


chrisg - 23/5/03 at 06:38 PM

Sorry but you're ALL wrong

Electricity works by smoke in the wires

Everything works until the smoke comes out.

(I can't do electrics, but I can lift heavy weights, me)

Cheers

Chris


Northy - 23/5/03 at 06:46 PM

Ah, that'll be the 'magic smoke', they also put that in the chips

[Edited on 23/5/03 by Northy]


Peteff - 23/5/03 at 08:57 PM

Cheers Chris, I know why my angle grinder packed up now. Lots of smoke and very hot. Do they do refills.

yours, Pete.


chrisg - 23/5/03 at 09:11 PM

You can put new bushes in them, this is a temporary measure to block the holes where the smoke is coming from...................................or something.

I'm not getting too technical for you am I?

Cheers

Chris


Peteff - 24/5/03 at 10:40 AM

I'll throw it away and get another Chris. That one had a curse on it anyway. Do they do wind up ones, I don't have much faith in this new fangled electrickery.
To depress a Renault clutch do you just tell it it's French.

yours, Pete.


chrisg - 24/5/03 at 11:46 AM

I can wind up my angle grinder

I say" call your self a power tool......you couldn't grind the skin off a rice pudding......etc"

Cheers

Chris