OK, I have not done any of this yet, but I am ordering the stuff to do
it, so take it for what it is worth.
My buddy is programming chips to measure stuff, do stuff, and display
stuff, it really is not hard, and uses some fairly simple programming
(he uses C, not too hard to learn) and relatively inexpensive stuff to
do it with ($50 programmer, chips for a few $$, some cheapo electronic
parts). He is a lab researcher, and built a robot thingie to feed his
flies, and is building a new one to sort them and cool them and do all
kinds of other things to them. It is really cool and really was not
much more than some tinkering and some fairly simple programming. You
do need to teach yourself, exercise the old gulliver a bit, learn
something new for the modern age! He is going to help me, has already
shown me some things, I can do it too! You have to buy the programmer
for the chips, all the software is free. Here are some links
This is the one I am going to buy:
http://cgi.ebay.com/USB-Microchip-MPLAB-PIC-ICD2-Debugger-Programmer-ICD-2_W0QQitemZ270050436515QQihZ017QQcategoryZ50915QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
It is a cheaper HK clone of this one, and all the info is here
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en010046&part=DV164005
The kits listed on this page are good learning tools. They have some
cheaper ones too that you can use to teach yourself what you need to know
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=2519¶m=en025315&page=wwwPICmicroDemo
This place has a lot of good tutorials and manuals and such, available
online, and free software too
http://www.mikroe.com/en/books
They are in Romania or somewhere, so shipping takes a bit longer, but works.
Make magazine had a series of articles on some simple PIC programming,
they have the Microchip (see above) device described here
http://www.makezine.com/blog/archive/2006/08/programming_pic_microcontrolle.html
This item (they have some simpler ones as above) would be more than
enough to do a prototype, teach yourself all you need to know, then you
can build the in-car device with just the sensor and display.
A PIC chip (they only cost a few dollars, simple ones like $3 or 4) can
be programmed to take signals, do something with that signal, and output
something based on that signal. So you get a sensor of some sort that
sends a pulse to a pin on the chip, time differences between pulses get
computed based on a simple little program, that difference gets turned
into an RPM, again based on some simple programming, and that number is
sent to a display device of some sort. You have to put the stuff on a
little circuit board, not too hard to figure out. There are lots of
schematics on how to do things like this, do some googling.
This place http://www.sparkfun.com/commerce/categories.php sells lots
of little gizmos and such, and if you do some web searches there are
tons of how-tos out there. This site has a lot too, as well as some
programmer kits and chips and such.
Have at it! Next we build a controller for the HVAC system!!! Maybe a
cruise control?
--R
R A Bennell wrote:
Very interesting but you will need to tell me more about how to do this. I took
some electronics in high school but
that was long long ago and I have not done much of that sort of thing since.
What all would I need to have a tach
setup on a 76 115 300D? Based upon what has been suggested in the posts over
the past couple of days, one should be
able to come up with a means of triggering some sort of signal from either a
crank sensor (magnetic??) or via a
photosensor of some sort. How to then use the signal to produce a reading on a
tach is beyond me. I read part of
Roger Brown's article on the photosensor setup on the Rabbit diesel and I
understand to some extent what he is
doing. I assume the signal from the crank sensor would be essentially the
same? IE - you get an electric pulse of
some sort on every revolution (or more than once depending on the setup) and
you use that to feed circuitry of some
sort that permits the tach to read it and tell how many pulses it sees. What
would I want for a tach? Roger Brown
is using a small digital tach. I guess the 300D might look more period correct
with an analog instrument of some
sort but this is not going to be something that I use for running up to redline
between shifts like one might do
with a hotrod Mustang so it really is not critical what it looks like so long
as it can be made to work well.
Randy
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of Trampas
Sent: Friday, November 10, 2006 4:10 PM
To: 'Mercedes Discussion List'
Subject: Re: [MBZ] Project to tickle your brains with..
The inductive pick up schematic is here:
www.patentranch.com/tempfiles/inductive_schematic.pdf
If you want me to send you one I can, note that the LM1815 has a maximum
voltage of 12V, thus it should be powered from a regulator. For those of you
wondering it was designed to be an interface board for the small engine
monitor I made, which incidentally I will be releasing as open source as
soon as I get my website redesigned. Also the OBDII device will be open
source as well.
Overall as mentioned before it is far easier to get the correct parts than
to hack something together.
Trampas
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
On Behalf Of Trampas
Sent: Friday, November 10, 2006 4:57 PM
To: 'Mercedes Discussion List'
Subject: Re: [MBZ] Project to tickle your brains with..
I have a small circuit board that will convert a crank sensor (inductive
pickup) to a TTL signal. I also have a device that has an LCD for displaying
the data.
The problem with the crank sensor is that as I recall it only triggers once
per revolution, I am not sure what the tachometer is looking for but I can
find out as I have a 300SD.
By the way here are some of the products I have built, www.sterntech.com
Trampas
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
On Behalf Of R A Bennell
Sent: Friday, November 10, 2006 3:47 PM
To: Mercedes Discussion List
Subject: Re: [MBZ] Project to tickle your brains with..
Yes, I saw the post yesterday with the link to Roger Brown's site. I knew
about him from my travels on the net
relating to old Toyota 4X4s.
The idea of using a crank sensor appeals. I just wondered what else I
needed.
Randy
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of Rich Thomas
Sent: Friday, November 10, 2006 11:37 AM
To: Mercedes Discussion List
Subject: Re: [MBZ] Project to tickle your brains with..
You could do an LED and a light sensor with a white mark on the crank,
of course that would be affected by whatever goop gets splashed up
there, but something to wipe it off as it goes around...
--R
R A Bennell wrote:
What triggers the crank sensor on most new cars? Is there a magnet
inbedded in the crank dampener/balancer/pulley
(whatever you wish to call it)?
IE - If I were to try this route to put a tach in my 76 300D, I assume I
would have to attach something to the
balancer to trigger the sensor as there would not be anything from the
factory.
Randy
-----Original Message-----
Given the relatively ready supply of junkyard parts, I can't see any
reason not to just use them, it's nearly trivial. (As I believe the
front crank sensor is already there, at least on a lot of cars. Goes
to the diagnostic socket.) Even if you have to install a factory
sensor, it has to be easier than flanging up something yourself.
And running it all over, and designing circuitry.
-- Jim
_______________________________________
http://www.okiebenz.com
For new parts see official list sponsor: http://www.buymbparts.com/
For used parts email [EMAIL PROTECTED]
To Unsubscribe or change delivery options go to:
http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
_______________________________________
http://www.okiebenz.com
For new parts see official list sponsor: http://www.buymbparts.com/
For used parts email [EMAIL PROTECTED]
To Unsubscribe or change delivery options go to:
http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
_______________________________________
http://www.okiebenz.com
For new parts see official list sponsor: http://www.buymbparts.com/
For used parts email [EMAIL PROTECTED]
To Unsubscribe or change delivery options go to:
http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
_______________________________________
http://www.okiebenz.com
For new parts see official list sponsor: http://www.buymbparts.com/
For used parts email [EMAIL PROTECTED]
To Unsubscribe or change delivery options go to:
http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
