Uselful bit of info AJ but the question everyone always used to want the answer to...Can the display constanly show the speed?

 

Yes it can - but thats why you have a speedo.
It can be done by itnerfacing a PIC or Atmel microprocessor which I started to do at one point but lost interest after blowing up the CPU. I'll buy another CPU and get started on it again if enough people want to be able to do it.
I could sell the kit to make it, offer up a list of parts if you want to source them yourself, or just sell a prebuilt kit.

 

Very useful, cheers AJ

Moved to tutorials

 

so am i right in assumeing you can make the MFD into a speedo?

 

Yes - speedo and rev counter

 

heh, AJ.. You know i am interested in this little "kit"..
if you do sell them, how much?
another thing.. i know the mfd only reads the speed once, does your kit keep refreshing the speed like a refresh rate in the mfd?

oh and a big thanks AJ this post is great!

 

The kit i designed will be able to keep the speed displayed on the TID constantly with the engine running. and will have a refresh rate of 8MHz - well the CPU is 8MHz.

All I need is some more CPU's, its best to buy these in bulk since the postage per CPU bought seperate pretty much doubles the price, then its the PCB that would need to be mass fabricated, but I might just etch them myself and drill them myself as well.

I'll order a single CPU at the end of the month, probably about £10-£15 and then I'll start redeveloping it. Theres only like 2 places you can get them from online.

The only pain in the butt would be the fact that the speed reading would be engine dependent.
ie, a 1.2 8v sparks at a different rate than that of say a 1.6 12v.
I'de need to find an easy way of getting this sorted accuratly, whether thats by using a potentiometer (not very accurate) or a couple of DIP switches, or just program each CPU with the correct timings before shipping it out.

 

hmm, well i am not fussed about rev range on the TID/MFD.. just the speed.
i guess this, but it should still work on a diesel... right? (the speed but not the revs)

 

id defo have some of tha, i could post you my MFD you work ya magic and post it back?

 

I would be an add on board, simply disconnect MFD from the car wires, and insert the board inbetween the two

 

oh right, get one made up and il be your guinea pig lol il pay for it obviously but i think it would be awesome!!!

 

AJ's start to world domination, one corsa at a time.. lol

8mhz.. thats quite a fast refresh rate.. faster than my dads bikes speedo :/

 

Sig'd

 

Obviously this is the fastest the CPU can run at, but take into account the commands that will be running, and i'll probably enable the CKDIV8 pin, so it will run at more like 1MHz top speed, but the MFD might bottle neck it if it can only refresh itself at a lower speed

 

Sounds like a pretty cool project so will be keeping an eye on this thread - keep us posted :thumbs_up:

 

hahaha i made some ones sig!!.. and not out of stupidity at that!

if this was facebook:

AJs comment. [Like!] <clicked

hmm in my case its [Arr!] (pirate talk ftw!)

dono if you got my last PM.. if you did sorry it was all over the place, i was almost asleep when i sent it LoL

 

Yeah I got it mate, bit curious to see where you would put the nixies though, its been buggin me all day lol

Back To The Future

 

Yeah I got it mate, bit curious to see where you would put the nixies though, its been buggin me all day lol

Back To The Future

what i would like to do is have them just above the MFD.. sticking up..
just 2 IN-14 or IN-16 tubes. would look mint.

only thing id have to figure out is how to link up the nixis to the MFDs LCD display.
if i could do it with a PIC micro controler or somthing else.
thing is,this is technology i am not familiar with. so ill have to learn as i go.
always fun.

ahh thanks man, that woud be real cool. i have seen the clock kits you can get on ebay and just thought i could tap into one of them.
be pretty sweet having a 4 tube clock (working from the radios live) that turns into a speed readout once you provide a ignition live.

[shock]150v[/shock]

thats why i was going to hack one of them clock kits, as they only work of a 12v plug in the wall addaptor lol

AC or DC it does not really matter (but AC gives the cool 50/60hz flicker... old style)

i was going to look for a way to hack >>>This<<<. As its nice a small and i could fit it some where and make a nice neet job out of it. but it was not the style of tube i was after.

then i found >>this happy little fellow<< and thought it was a good price for the ammount of tubes you get.

But, it has no power supply. now i could make one or i could buy >>>This<< to save me the hassle.

these are the 2 types of nixie tube i wanna use:

can see that the small one is the IN-16 and the big one is the IN-14.

and in responce to your question, yes it basicly is just earthing the pin to what number it is you want to display.

Depends, do you want Kph or Mph? its a simple conversion so not a problem.
Also, that guy on the above site is usint the ATMega128, same as me but I will most likely use the ATMega324p. Or the ATMega8.He went about it the long way round though, look at the size of that PCB! lol

just the bolds bits! lol

 

where i would put them? im thinking 4D.. you have to go back in time to fit them.

heh

what i would like to do is have them just above the MFD.. sticking up..
just 2 IN-14 or IN-16 tubes. would look mint.

only thing id have to figure out is how to link up the nixis to the MFDs LCD display.
if i could do it with a PIC micro controler or somthing else.
thing is,this is technology i am not familiar with. so ill have to learn as i go.
always fun.

 

Sounds good. I have never played with nixie to be honest, but I'll see if I can dig up any info on interfacing them with a micro cpu

If I get it working with nixie, I'll build you a one off

 

ahh thanks man, that woud be real cool. i have seen the clock kits you can get on ebay and just thought i could tap into one of them.
be pretty sweet having a 4 tube clock (working from the radios live) that turns into a speed readout once you provide a ignition live.

or make it a time delay live so for a few secconds it displays the time, then swiches over to speed. but only when the ignition is turned on.

hmmm.. so many plans, so little uhh.. experance. lol

oh on another note, (bit OT, sorry) i booked my driving test for the 19th of next month i got a dead line now to get my car on the road :/

 

Just found this image below.

Am I right in thinking that that you just provide a ground to the pin that you want to illuminate, and positive to the anode?
If so, it work similar to the 7 segment displays.
So shouldnt be hard to implement.

What voltage do they run off of, because I read somewhere that its around 140vac

 

[shock]150v[/shock]

thats why i was going to hack one of them clock kits, as they only work of a 12v plug in the wall addaptor lol

AC or DC it does not really matter (but AC gives the cool 50/60hz flicker... old style)

i was going to look for a way to hack >>>This<<<. As its nice a small and i could fit it some where and make a nice neet job out of it. but it was not the style of tube i was after.

then i found >>this happy little fellow<< and thought it was a good price for the ammount of tubes you get.

But, it has no power supply. now i could make one or i could buy >>>This<< to save me the hassle.

these are the 2 types of nixie tube i wanna use:

can see that the small one is the IN-16 and the big one is the IN-14.

and in responce to your question, yes it basicly is just earthing the pin to what number it is you want to display.

 

haha... this guy made the display say "ass" in polish

Childish, but funny!

 

thats a good find, theres a few links to other mods on his site too!

well done!

AJ, one things got me thinking.. will the TID read out speed in KM/h or MP/h?

 

Depends, do you want Kph or Mph? its a simple conversion so not a problem.
Also, that guy on the above site is usint the ATMega128, same as me but I will most likely use the ATMega324p. Or the ATMega8.

He went about it the long way round though, look at the size of that PCB! lol

 

So if you manage to do this it'll be a case of just plugging something into your mfd and it'll show your speed? Would it be possible to incorporate some sort of switch so that you could choose speed/time?

 

Yeah should be simple enough.
If one of the pins on the CPU is pulled low, it will show the time, otherwise it will show the speed