Hey guys,

Im having a little trouble getting an rpm signal. I can get one using the stim but i cant get anything with the cas hooked up. I can get voltage out of my cas through the harness, 1.7v for the 24 tooth and .2v for the 2 tooth by spinning the cas with a drill. Any ideas?

Thanks,

Ian

 

How did you build the 2nd VR circuit? did you follow H4inf's guide for wiring the LM1815? If you do follow his guide, i recommend that you connect pin 14 to ground instead of to the RC circuit.

Also, its a pulsating signal, and measuring it with a voltmeter won't give you accurate measurements. You really need an oscilloscope, or a program that uses your microphone input as a o-scope

 

Is your engine properly grounded?

Edit...Wait, you said you got an RPM signal on the 'Stim. Are all your jumpers set correctly on the board? If the 'Squirt is configured to accept an RPM signal from the 'Stim (I am assuming a regular 'Stim and not a JimStim) then it won't be able to read the CAS.

 

Thanks for the quick response.

I do have my jim stim set up to emulate the signal of the cas.

For my 2nd vr circuit i followed jobro's guide and then i burned something up and couldnt figure it out, so i sent it to Peter Florence and he did ensure(after fixing) that my vr circuits worked. As for my engine being grounded properly, i am in the process of rebuilding my engine and installing the squirt so right now i have had the cas out of the car and using a drill to spin it.

Do you guys recommend any o scope program?

Thank you

Ian

 

Here is the basic tune im using, this is by no means final so it may in fact be the culprit. Hopefully somebody has a little time to look at it and give me some feedback.

Thanks

Ian

 

OK, I don't have the correct INI files for your MSQ on my office machine, so there were 72 warnings when I opened it up in MegaTune.

If I have the file opened correctly, your settings are all wrong. I'm not sure really where to begin.... Required fuel should be closer to 10 because at 4.4 you will run out of VE table. It should be set to two injectors not 4.

Trigger angle needs to be 60. Ignition capture should be Falling Edge, spark output should be Going Low. Under Ignition Options you have rotary mode turned off. Trigger settings look OK.

There's a bunch wrong. I don't have a base map for your firmware version otherwise I would give you a place to start.

 

Ok, i went in and made the changes that you suggested, still not getting a signal from the CAS... What i noticed was that after changing from going high to going low the led's i have set up on my jimstim to show spark stayed on. Hopefully you guys have some more ideas to help me through this.

Here is the msq i updated a little bit.

 

For a reference if anybody else runs into this problem. I finally got it working after moving the ground for the second vr circuit from pin 36 to pin 1 in the db37 connector.

 

Trigger angle and Input capture edge are both dependent on configuration of the engine and wiring.

Wired correctly with TSEL connected to VROUT (not VROUTINV) you'll want rising edge on the input capture.

60 degrees for the tooth #1 angle is only correct if you stab your CAS specifically for that setting. If you stab the CAS like stock, you actually want a 5 degree tooth #1 angle.

Ken

 

Right. I just copied values from an MSQ I had lying around without thinking much of it. Soon I'll be PM'ing you to check over the MSII stuff in my Megasquirt writeup...

 

Alright I will take a look when you send it.

Ken