VR circuit with EDIS - need testers

[Bruce Bowling]

I am trying to determine if the VR input circuit on the V3 board is sufficient as-is to support EDIS PIP, eliminating the need for the mods to the opto circuit.

So, if someone wants to test this, it would be helpful. Set up the V3 board so tachsel is to vrin. Also I believe that the inverted vr signal out vroutinv needs to go to the tsel signal (someone verify if they could), otherwise it is the vrout signal going to the tsel.

Set the threshold pot (bottom pot) up several turns CW to raise the threshold (or more if needed). Also there is a 1 meg resistor to pul the input up (really, 1,002K with the two 1K resistors) and this should be sufficient, but if not then parallel the 1 meg resistor (R51) with something like 10K or so. The 1 meg resistor is there to act as a very weak pullup in case a VR sensor is disconnected, but it may be too weak to provide sufficient pullup for transistor switch inputs.

Also, the VR input should also be useable for hall inputs as well (connect to hall sensor collector)- same setup as above, and there may need to be more bias applied to give more collector current.

If people can try this out it would be a big help, we can then point people to use this circuit instead. It really helps the distributors who are building kits, too. It may make sense to have the kits default to VR input and only change to opto input if the application is primary ignition coil trigger - and I really think that this could be also replaced with the VR input circuit with a little tweaking.

- Bruce

[Keithg]

Great idea! This would also allow for 2 conditioned inputs for dual
wheel as well which would be well configurable.

Watching with interest.

KeithG
Posted by email.

[Bruce Bowling]

[quote="Bruce Bowling"]I am trying to determine if the VR input circuit on the V3 board is sufficient as-is to support EDIS PIP, eliminating the need for the mods to the opto circuit.

So, if someone wants to test this, it would be helpful. /quote]

I really could use some data on this, i'll help us guide the documentation....

- Bruce

[Peter Florance]

I can do it tomorrow night. I left my MS'd car at home today...
 
Is that ok?

Peter Florance
First Fives.Org - The E12 Registry
1981 Euro BMW 528i w/3.5L & Megasquirt Fuel Injection
1981 US BMW 528i "Repo Car"
http://www.firstfives.org
mailto:peter@firstfives.org (peter@firstfives.org)
ssr# 284
 

-----Original Message-----
From: Bruce Bowling [mailto:bbowling@earthlink.net]
Sent: Monday, March 27, 2006 3:33 PM
To: megasquirt-mss@msefi.com
Subject: VR circuit with EDIS - need testers

I am trying to determine if the VR input circuit on the V3 board is sufficient as-is to support EDIS PIP, eliminating the need for the mods to the opto circuit.

So, if someone wants to test this, it would be helpful. /quote]

I really could use some data on this, i'll help us guide the documentation....

- Bruce



This post is at: http://www.msefi.com/viewtopic.php?p=110437#110437

Posted by email.

[Bruce Bowling]

I can do it tomorrow night. I left my MS'd car at home today...

Is that ok?

Thanks, Peter, for the assistance! Its one step towards a unified tach input...

[Peter Florance]

Yes it works.
I forgot I had a 3.00 board I was repairing.
 
EDIS-6 and my 36-1 stim (pic based)
 
Stuck pip in tach in. With no rpm I adjusted threshold on U7 pin  3 so comparator voltage was about 2.5 volts.
 
Nice and clean square wave output from opamp. Works up to about 7300 rpm where my stim falls apart.
 
 

Peter Florance
First Fives.Org - The E12 Registry
1981 Euro BMW 528i w/3.5L & Megasquirt Fuel Injection
1981 US BMW 528i "Repo Car"
http://www.firstfives.org
mailto:peter@firstfives.org (peter@firstfives.org)
ssr# 284
 
 
 
 

-----Original Message-----
From: Bruce Bowling [mailto:bbowling@earthlink.net]
Sent: Monday, March 27, 2006 4:59 PM
To: megasquirt-mss@msefi.com
Subject: VR circuit with EDIS - need testers



Peter Florance wrote: I can do it tomorrow night. I left my MS'd car at home today...

Is that ok?



Thanks, Peter, for the assistance! Its one step towards a unified tach input...



This post is at: http://www.msefi.com/viewtopic.php?p=110454#110454

Posted by email.

[Bruce Bowling]

Yes it works.
I forgot I had a 3.00 board I was repairing.

EDIS-6 and my 36-1 stim (pic based)

Stuck pip in tach in. With no rpm I adjusted threshold on U7 pin 3 so comparator voltage was about 2.5 volts.

Nice and clean square wave output from opamp. Works up to about 7300 rpm where my stim falls apart.

Thanks for the testing, Peter! I am pretty confident that the VR conditioner circuit will work for EDIS, TFT, and hall inputs by adjusting the threshold like you did. The only additional circuitry that I coul imagine would be a pullup to +5V on a hall sensor, but the 1M in the circuit may be sufficient.

- Bruce