To all Microsquirt users, please chime in.

[kamaro]

I'm trying to wire a Microsquirt to my 3.2 engine here, all went very well, except when I tried to wire the WLED to ignition C (using wasted spark, I need to use Ignitions A,B and C for the 6 cylinders), I can successfully test ignitions A,B, but C,D wont spark, I have a 1K ohm pull-up resistor between WLED and the 5 volts ref. connection as per the tech. manual. I'm using COPs from a Toyota.

For the Microsqurt guys : How did you wire your 3rd ignition wires?

[timmy2]

I heard recently that a 100 to 150 ohm resistor is all you need.
Others will likely chime in.

[Bigtoe32067]

Im not sure either but I’m going to be attempting something similar in the future. Keep in mind I have no idea what I’m talking about, only asking questions but why not use megasquirt and wire the cops in directly and same with the injectors. Wouldn’t that give you better control over timing and fueling so you could run hotter cams, timing, etc.
Is it not necessary?
Is the cost differential too great with the megasquirt?
I see a lot of people doing it your way with the micro instead of the mega and wondered.
I don’t understand the 100k pull up resistor between the wled comment or a lot of the comments people have made about modifying the micro so I thought it would be easier going mega Which is why I was contemplating that route.
I guess my long winded question was why micro over meg or vice versus.
If it’s too involved and I should start a separate thread please tell me. I won’t get my feelings hurts.
Thanks
Tony

[kamaro]

Originally Posted by timmy2

I heard recently that a 100 to 150 ohm resistor is all you need.
Others will likely chime in.

I tried going low to 470 ohm with no luck, if I connect a digital volt meter to the WLED output I can since the pulse when ever I hit the "test" button in the software, so at least I know something is happening. I will try to use a 150 ohm today and see what will happen.

[kamaro]

Originally Posted by Bigtoe32067

Im not sure either but I’m going to be attempting something similar in the future. Keep in mind I have no idea what I’m talking about, only asking questions but why not use megasquirt and wire the cops in directly and same with the injectors. Wouldn’t that give you better control over timing and fueling so you could run hotter cams, timing, etc.
Is it not necessary?
Is the cost differential too great with the megasquirt?
I see a lot of people doing it your way with the micro instead of the mega and wondered.
I don’t understand the 100k pull up resistor between the wled comment or a lot of the comments people have made about modifying the micro so I thought it would be easier going mega Which is why I was contemplating that route.
I guess my long winded question was why micro over meg or vice versus.
If it’s too involved and I should start a separate thread please tell me. I won’t get my feelings hurts.
Thanks
Tony

Hi Tony,

The main (and only) reason is cost, $300 vs $1300 for the MS3. And to be honest, the micro is all what I need to get my project run correctly.

[Bigtoe32067]

Thanks. I’ve heard that also from other so I may change my goal to micro.
I will just need help to add things to it to make it work but hey, I’m always up to learning new things. That’s one reason I’m attempting all this.
Good luck with your project
Tony

[kamaro]

Originally Posted by Bigtoe32067

Thanks. I’ve heard that also from other so I may change my goal to micro.
I will just need help to add things to it to make it work but hey, I’m always up to learning new things. That’s one reason I’m attempting all this.
Good luck with your project
Tony

We are on the same boat. I'm really trying to figure out almost everything with my project, and thats why I choose to go with the micro, so at worst case I will lose $300 instead of a hefty $1300!

[kamaro]

Originally Posted by timmy2

I heard recently that a 100 to 150 ohm resistor is all you need.
Others will likely chime in.

You are exactly right!, I tried a 180 ohm 1/2 watt resistor and it worked. now is a 1/2 watt is all what I need or do I need to go for a bigger one?

[timmy2]

It is a pulse signal just boosted to 12 volts. Not a lot of current.
You should be fine with the 1/2 watt I would think.

[al lkosmal]

I've recently tested the Microsquirt logic level outputs with smart COPs, 2-wire dumb cops with QuadSpark igniters and firing an EDIS-6 coil. I started out with the recommended 1Kohm resistor and got intermittent spark from output C. Once I installed a 125ohm, 1/2W resistor and ignition output C came to life and all of these ignition options all seemed to work well.

https://www.youtube.com/watch?v=S1TUpoc43co
https://www.youtube.com/watch?v=K095f-5ZNVA

regards,
al

Note: I found two different resistor values documented for the Microsquirt. 1Kohm (Microsquirt hardware manual) and 100ohm..........(DIYAutotune Ignition instructions)