RPM input issue on a Microsquirt

wes kiser · Post by **wes kiser** » Fri Oct 26, 2007 11:10 am

I'm trying to help UNCC's fsae team again, and can't get MS2 Extra to pick up RPM on the microsquirt. I have tried the latest BETA (14?) as well as the old BETA I was running previously (9). Standard B&G code works. All other inputs seam to work. It is a single tooth crank wheel on a 1 cylinder, so essentially it would be a trigger return distributor (2 cylinder input everywhere in software). Right now I am just trying to get RPM, will work with the other problems as they arise.

When looking at the wiring schematic, there should be no difference from a code standpoint with RPM, but I have two ecu's here, and the behavior was the same on both.

How critical is the degree value between faces of the tooth on trigger return? This parameter would not keep it from syncing would it? I have tried both rising edge and falling edge as well. Thanks.

Post by **muythaibxr** » Fri Oct 26, 2007 11:40 am

You are the first person I know of trying to test ms2/extra on a microsquirt.

James or I will take a look at the problem and see what we can come up with.

Ken

Post by **jsmcortina** » Fri Oct 26, 2007 12:58 pm

Did you compile the code to create a Microsquirt executable?

make microsquirt

then
download the right s19

James

wes kiser · Post by **wes kiser** » Fri Oct 26, 2007 12:58 pm

It may also have something to do with the trigger itself, as I don't have a practical way to hook a standard squirt up to it.

It is a single (wide tooth) on the crank. It is definately trigger return, as I scoped it with the engine cranking. It falls, then rises back to zero, then stays zero for a "pause", then it rises. Looking at the geometry, the leading edge is at about 40 DBTDC, and then the tooth is approximately 30 crank degrees wide. We are reading it with the standard KTM (this is a 525cc KTM single) CR sensor. Last year I had the engine running with a 36-1 wheel on an MS2 running extra Rev 1.0(which has since disappeared). We are initially getting a decent base tune in fuel only with the factory CDI box handling the spark, before I attempt to get good spark control with this wheel.

In B&G 2.88 (I think that is what the micros come with now), I simply selected "standard coil charge" and trigger return. With the proper number of cylinders (2, since it is a single tooth crank wheel)this gave a reasonable cranking rpm. It should be noted that that code requires you to select MS2 or microsquirt before you do anything else (I mentioned this because I do not know how familiar you guys are with the micro).

With Extra 2, I assumed this would essentially be a trigger return distributor on a 2 cylinder. I also tried with basic trigger, but no luck.

wes kiser · Post by **wes kiser** » Fri Oct 26, 2007 1:00 pm

jsmcortina wrote:Did you compile the code to create a Microsquirt executable?

make microsquirt

then
download the right s19

James

I'm sorry, I don't quite follow?

Post by **jsmcortina** » Fri Oct 26, 2007 1:03 pm

I'll hook up my Microsquirt sometime soon and take a look. I wrote some compatability code, but I'm not sure if I really tested it. As noted above you need to create a new executable.

(Tech: There's at two ways to handle the different hardware - either do it at runtime and choose which port to use with "if" or pointers, or compile it in with #ifdefs. Seems Al chose the former and I chose the latter!)

James

Post by **jsmcortina** » Fri Oct 26, 2007 3:22 pm

MS2/Extra doesn't use a common binary. A specific s19 is compiled for each target. This seemed like a good idea at the time.

The next beta code should feature both codes pre-built and the downloader has been updated to ask which one you want.

Send me a PM with your email address (or jsm@jsm-net.demon.co.uk ) and I'll send you the current s19 for MS2/Extra Microsquirt.

James