PULSE RMP GENERATOR

[ernesto1670]

Hi Dk `s
I would like to make a RPM GENERATOR (for testing). I have seen some online, but can not find the schema. Anyone have the diagram to make it.

thanks

Excuse my bad English

[jonniebravo]

basically there are two types hall effect and inductive, what do you want to emulate?
hall effect is easier, being pulsed, and inductive generates AC signal.
you have to know what type of car you are emulating, because number of teeth and their width is different....lets say on most cars you have 58 teeth and two teeth that are out so you get something like this:
http://www.picoauto.com/waveforms/Sensors/Crankshaft/wave105.html

[ernesto1670]

basically there are two types hall effect and inductive, what do you want to emulate?
hall effect is easier, being pulsed, and inductive generates AC signal.
you have to know what type of car you are emulating, because number of teeth and their width is different....

for example .... pumps, power steering (EHPS and EPS) need RPM pulse, for its functioning. This may be one of the utilities.

tks

[jonniebravo]

i think that power steering gets it signal from ABS....anyways, easiest way is using microcontroller like pic or avr to generate impulses, display to see whats going on, few buttons and FET or npn transistor to get output signal to desired level(12V). I can do some sample code and schematic, but can't promise anything...i got time now but tomorrow who knows...

[ernesto1670]

i think that power steering gets it signal from ABS....anyways, easiest way is using microcontroller like pic or avr to generate impulses, display to see whats going on, few buttons and FET or npn transistor to get output signal to desired level(12V). I can do some sample code and schematic, but can't promise anything...i got time now but tomorrow who knows...

ok, no problem.
Time is no problem,
Thanks for the contribution

[smokey08]

Have a read up on 555 timer circuits. I think this is what your looking for.

[jonniebravo]

it could be done with ne555....but with extra discreet electronics...there's probably someone here who's good with that...555 can generate pulses, but we need something that will count those pulses and when it counts 58 pulses then pull up signal for two full periods...yeah it could be done, i will search for that kind of solution too, but i think its more elegant with microcontroller.
actually i analized a bit more signal from opel vectra, before that "big gap" signal should go to ground for one full period.

[jonniebravo]

http://i43.tinypic.com/9usww2.jpg

[nutloose]

do it with a pic micro
is probably the most flexible way.

edit:
I found this old app that I wrote in assembly language to simulate a ckp output. the source code is there too so if you modify and reassemble it you can make it do what you want. (edit the pulse, gap in main)

[jonniebravo]

thank you nutloose, but i don't write in assembler, it's to "hostile" for me, haha, i have already idea how to do it, i'll do it tommorow probably.

[roth18]

UPA has a generator built in.

Don't know if it is OK for you purposes.

A

[Meat-Head]

hi sorry on a cell pphone on "the polar express "

look for vellaman.be

thry make all sorts

try futrekit.com sorry no spell check

simple multivibrater 2resistors 2capacitors 2transistors

[nutloose]

jonniebravo (http://www.digital-kaos.co.uk/forums/members/47652-jonniebravo/)
I didn't expect you to write any assembly language.
Just find the "main" loop and edit it to read the correct number of" call gap" and "call pulse" statements to represent the pulse profile you want. Then recompile into a new program.
It puts the square wave pulses out on the four lower data lines of your parallel port . (use an OLD (386 or 486 etc) pc or laptop or it will run too fast)
I think the gap is about eight times longer than the pulse

I still think a pic or mbed would be more flexible and you could write it in C which is much easier.

[Meat-Head]

nutloose there is a programme to slow processerss down cant remember the name

OFF TOPIC

when running win ce the speed your prograamme runs at is at speed of your pc

but this that and the other wont run ta full speed

must be a slow down prog for virtual win ce?

[jonniebravo]

i'm writing it for the pic, i hope it will be over this week(today maybe, for the bosch hall-effect type), had no time to write code, sorry. For inductive types, it needs some extra electronics, i will write later on...
Just to say there's like five or six types of signals for hall effect sensors and for inductive types also.
I also plan to simulate camshaft sensors, but that's for later on, as they need to be in phase with crankshaft signal and i am trying to find as much data as i can. Chiptunners are welcome to help...