No cranking/ Microsquirt could not read rpm

[banchat]

We are using both megasquirt and microsquirt. We can use megasquirt to operate on the engine well.
Base on the same engine, we face a problem when replace to Microsquirt; no cranking or not able to read rpm.

We also have checked using Tooth Analyzer and found that tooth wave were detected. However we can't read rpm on Megatune. We certainly not confuse in embeded code between two kind of .s19 files and two kind of cranking sensors.

Do you have any recomend I could check. Or problem caused by some setting parameter.

[grippo]

If the tooth analyzer looks good, then it may be a configuration problem. It would help if you posted the msq files for megasquirt and microsquirt. Also, engine: how many cylinders, what type crank wheel, is there a cam synch, what type ignition ?

[banchat]

Here they are the info;
- Engine Nissan VQ20 6 Cylinders
- Crank wheel is Hall sensor type, Crankshaft position sensor (CKPS/REF)
- No crank synch
- Ignition type --> we still use the signal from origianl Nissan ECU
- Monitor V2.89 and Monitor_v2.890.abs.s19 were performed
and also we attached two msq files, HCCI_part_two.msq is for Megasquirt and megasquirt200903311617.msq run on microsquirt.

Actualy Microsquirt were desired to controll 50cc-engine in our lab, but we couldn't detect the rpm. So we tried to test the microsquirt on Nissan engine instead using Megasquirt which achieved already.

[grippo]

Looking at your msq for the microsquirt, you have it set up for dual spark / wasted spark mode for a 6 cylinder. Microsquirt only has 2 ignition outputs so it can not handle a 6 cylinder in this mode (possibly the extra code handles this, but I am not sure if it has been tested yet). The megasquirt msq is set up for a distributor, so if you set the microsquirt up in that mode it should also work. The new sequencer, currently in beta testing, will handle the 6 cylinder with a toothed wheel.

[banchat]

Thank for your info, we have concentrated more on Ignition-setup and got the rpm. However we still don't understand much how we can setup the parameter properly, hence we have attached the picture showing the Tach signal hardware. This is for 1 cylinder 50cc engine.
This system shows the pulse signal every evolution. We tried to adjust Advanced Ignition Option>Trigger Wheel Teeth(teeth) and found detected in rpm. But rpm is still not correct.
What kind of this Tach signal? Is it reasonable to count it as Trigger wheel setting for my Tach signal as shown in the picture.

[grippo]

This looks like a single wide tooth. In this case you should NOT use the dual spark or trigger wheel options. Set No_Teeth = 0. If this is working on megasquirt, you should be able to get it to work on microsquirt with the same settings except you will probably have to change the polarity of the trigger sensor and maybe even the spark output because I believe one or both of these are different with microsquirt. And of course set the ECU type to microsquirt. You should be able to get rpm like this. If you don't, but you do get a nice waveform with the tooth analyzer, then post the exact msq you are using in microsquirt on the 1 cylinder. Let's forget about the 6 cylinder.

Your setup will allow you to use the trigger return starting option. This means you can set it up so that it fires on one edge of the tooth during cranking with no advance, so there is no timing error during cranking, which is important for a single cylinder engine, then after cranking it switches to the other edge and adds in normal table advance. But don't worry about this right now - it is just something to consider if you get a lot of lost synchs during cranking because the engine is very jerky from the explosions.

[chlin]

Here are the two files that one is .mal the other is .msq,and i can see the rpm at the same time ( use microsquirt).
But the idle speed is the wrong value(up 16000rpm)and the real idle value is about 1800rpm.mabye i do not set up correctly.
banchat is my senior and he helps me to slove this problem and my english is poor,pardon me.
thx
best regard
chlin

[grippo]

Your datalog deltaT column shows that the time between rising edges of the wheel is about 14000 microsec, which is 1 wheel rev per .014 sec or roughly 4000 rpm. The rpm column shows roughly double this because it is in distributor mode and assumes the pulses come from the dizzy. I don't know how to correct for this in the configuration with the present code. I don't think it will work with a 1 tooth wheel.

But more important, I don't understand how it can be that the actual rpm is 1800. The deltaT is the raw time in microsecs between pulses of the wheel sensor - it is just the difference in times. I have never seen it be wrong.

Secondly, you have a lot of electrical noise getting into the wheel sensor signal. This can be seen by the Trigger+/- column. By the time you started the dialog it had already seen about 5000 extra pulses arrive. It counts up when a pulse comes in that is out of tolerance with the previous deltaT time, then it throws out this extra pulse if it only happens once and then the next pulse time is good. But then it can keep going like this. You might try changing the setting on the acc_synchk input from Always to Never check for synch or only check when no accel. See if either of these changes help any. Also, first check that there are no wires laying across spark plug cables.

The last question I have is does this work with megasquirt on this same engine, wired the same way, with the same msq except the minor changes needed in polarity and ECUType ? That is do you get correct rpm and no noise problems ?

[chlin]

hi,now microsquirt read the idle speed about 4000rpm,and can i tune the injector flow bigger or more little to suit this idle rpm?
because the actual engine speed is about 2000rpm,just like you said it is diploid .
and what should i have to regard?

what i mean is i know the value is double however i use the microsquirt.and i tune the other parameters to suit real engine speed.

this engine is used for supermilage that used injector to squirt fuel...

best regard

[grippo]

What I would do is install a 36-1 toothed wheel - that will give you the best control over ignition and fuel timing. Then run it in dual spark mode and you will get the proper rpm as well.

As far as what you can do with the present wheel, just ignore the real rpm and set up everything as if the rpm on the pc is the real rpm. So if you see 3000 rpm on the pc, then you adjust the ve bin for 3000 rpm.