Thread: Discovery 2 ABS signal - analogue or digital?

digital, hall effect sensor style, the numbers are in the RAVE and from memory its a 5v interupt logic value.

I am still confused,i thought that hall effect style sensors have 3 wires and that the 2 wire sensors(disco 2 style) are inductive coil speed sensors.
I'll check again tomorrow-thanks.

Originally Posted by fatman

I am after these problems..
http://www.aulro.com/afvb/discovery-...placement.html

http://www.aulro.com/afvb/discovery-...-searched.html

If i got it right so far the slabs ecu creates a digital output speed signal to the rest of discovery 2' ecu's, from speed readings from the 4 abs sensors.
Do the sensors send an analog signal(say 0-12-0 volts) to the slabs ecu so i can more easily recalibrate them before entering the slabs ecu?
Please help me on this..
Thanks.

The best way to recalibrate would be to modify the speed output of the SLABS unit. The SLABS ECU sends a 0-12V PWM digital signal at 8000 pulses per mile. This is much simpler to modify than attempting to alter four separate analog signals.

If you have skills with electronics & microcontroller programming the problem is fairly simple to solve. If not a truspeed unit will do the job.

cheers
Paul

Originally Posted by OffTrack

If you have skills with electronics & microcontroller programming the problem is fairly simple to solve.

I built a VSS modifier to optionally limit the speed provided to the ACE ecu - either unmodified, limited to 35 kph to get rough road handling at higher speeds or 2 kph to cause the bars to always be unlocked.

This thing is getting more interesting..
I was thinking something similar for the ACE and for the HDC witch is kind of "fast" for my taste on large slopes.
In case i can't find the tested(truspeed) solution,i"ll contact and electronic guru to describe what i want - and post more questions
Thank you all.
King regards.
Andrew.

Originally Posted by fatman

I was thinking something similar for the ACE

The 4 ACE boxes I've made were all on a breadboard which were rather fiddly to build and looked untidy. As pcbs can now be manufactured very cheaply ($14 for 10 50mm x 50mm), I've just designed a pcb. If there's any interest I'll get 10 produced along with a pcb to mount on the back of a rotary switch. Overall cost wouldn't be much more than $60 each. Bear in mind that it is hard-wired like the Truspeed unit, which BTW I'm not interested in replicating. It can co-exist with a Truspeed unit but needs to pickup the speed signal before it is modified by Truspeed.

Update..
Yesterday i 've contacted 3 shops that install taximeters(don't know the exact term in english) in to taxis nowdays with electronic speedometers but the can't help,whatever calibration they do is inside the taximeter - so no luck there.
I have a buddy that can built me anything on pcb's or other elctronic devices but can't help me on the design - i can't help him with my description either!
So if you have any circuit diagram you want to share,i'd be very grateful..
PS
I thought of a dimmer-potetiometer like device but as i understand i have to increase the pulses sent by the Slabs ecu to the rest ecu's,since larger tyres=less revolutions=less pulses?
Is this the correct desciption or i am telling the elctronic guys wrong things in ancient...chinese??

I don't know how Truspeed adjusts the pulse rate, bearing in mind that there's a base pulse even when not moving. My design either passes through the standard signal or outputs a pulse for a fixed speed instead because that's what it takes to get the specific ACE features.

I though the Truspeed was cheap enough to buy to not mess around trying to achieve the same thing.