MicroSquirt.com read only forum (Jan.15,2018)

OK is this information correct? I want to verify before I actually do the final install:

The info for GM DIS is confusing and scattered all over so this is what I know so far....

Hardware setup:
-Megasquirt II with optic isolator ignition input selected and high current ignition port setup with 1000k ohm 5 volt pull up circuit to protect the CPU.
-Saturn OB I GM DIS module.

Software settings:
-Megasquirt-II.ini:
Max Dwell limit reset to 25.00

-Megatune:
Ignition Input Capture: Rising Edge
Cranking Trigger: Trigger Rise
Coil Charging Scheme: Standard Coil Charge
Spark Output: Going High (Inverted)
Max Spark Duration: 25.0
Max Dwell Duration: 25.0

Now should the spark output be "Going high" since I installed the high current coil driver in my hardware setup? Most setups I see connect the CPU port directly to the ignition module.

Ok just trying to keep things straight before I finally install this!

kudos,
A.J.

Anyone?

bluetrepidation wrote: high current ignition port setup with 1000k ohm 5 volt pull up circuit to protect the CPU.

I pretty sure you just have to jumper the board for Hall sensor use ... you dont need a pull up circut....

Well i dont..

93 SC2

I didnt have to swap ign modules...

Just to make sure your fully aware you have to wire the VR(crank sensor) to the ICM. and so on... but yea... anywho ...

I didnt think about changing the max dwell to 25 in the .ini file... hmm maybe that would get rid of my surge....

OH really!? Interesting. So you had to wire your hall sensor directly to your ignition control module? OK now I'm extra confused. Let me clarify by asking you if your ignition control module looks like this?

http://www.electronicdisposition.com/OBISaturnGMDIS.JPG

A.J.

yea, I have that unit, a 91-95 ICM(ignition control module)

Sorry i wasnt trying to confuse you

the ICM that Saturns use from 91-95 act just like a Hall sensor... So there is no need to wire a Hall sensor in ...

I just ment you set up the MS pcb board like you would for a hall/optical sensor.

On my v3 PCB the builder put both circuts on ... and I just selected the hall curcut with Jumpers...

Im not TOO shure about the 99's check but from 96-98 i believe that they re routed the VR sensor input to the ECU instead of the ICM...

Hence why you have to use the 91-95 ICM and Wire the VR sensor to it... and a couple other wires to the MS...

I dont know if you saw this thread but it may be helpful for you ... IM running a v3 MS2 so i just used this to get a Base to jump off of...
http://www.msefi.com/viewtopic.php?t=7142&highlight=dis

And this is one I started after getting Fuel and Spark running on my 93 SC2 ...

http://www.msefi.com/viewtopic.php?t=15 ... aturn++dis

but im sure you already read this page...
http://www.megasquirt.info/ms2/GM_DIS.htm

Im not sure if you check another sight out that MOST LIKELY has Alot of good info and people that could help you further... check here at TSN

http://www.turbosaturns.net/

Whew ok. Yeah any 96 and newer Saturn has the hall sensor wired directly to the ECU. I thought for a second you got a OB II ignition control module to work! Now I am wired for the hall setup. Where I differ is I do not have JS10 jumpered to IGN. I hooked up the high current coil driver circuit with a 5 volt pull up resistor so I could protect my processor port somewhat. So you think I don't need the pull up resistor? Otherwise thanks for the link on using an LED for the bypass circuit. This is what I was planning on figuring out next.

A.J.

are you using the MS2? The ms2 has it built it, so you wouldn't need to wire that in. I don't think it would hurt to have it however.

tebriel wrote:are you using the MS2? The ms2 has it built it, so you wouldn't need to wire that in. I don't think it would hurt to have it however.

I know the processor port has built in pull up but I'm using the high current coil driver circuit on the V3 board to drive my ICM. This doesn't have any kind of pull up does it? Anyway it's added but I'm still not sure when kind of output setting I need to use. To invert or not to invert?


A.J.

is there any reason why you're choosing to drive the coil?

wait, are you driving the coils or are you driving the ICM? You don't need a pull up when you are controlling the ICM. You just hook your tach signal from the ICM to the MS, then on MS2 put pin 36 to the EST in wire on the ICM. Then you just need to worry about the bypass signal to the ICM.

you read turbosaturns.net or plastikracing.net? they both have posts about doing this
-teb

OK well the above setup officially works! I don't know if I needed the pull up resistor but it is in there and my processor port is protected so I'm happy. I also got a spare output setup for my cooling fan and my bypass wire on my ICM setup. All works. Now the car did surge but shutting off EGO correction fixed that. The cooling fan kicking on causes a bit of load but hitting the brake lights doesn't seem to affect anything. So far so good.