I just got done building my Megasquirt, plug it into the computer, plug the stim in.

Get Idl light on stim, but cant connect to it with Megatune.

Everything i try doesnt work... any ideas ?

 

If i use "portcheck utility" i get
"
Com 1 opened
9600 baud
"bowling & grippo v.2.xx or 3.000"
115200 baud
no connection made
"

 

OK i did the hyper terminal test, with a jumper the letters are relayed back, with the Chip in they are not.

 

Are you actually connected on COM 1? On my last laptop, it defaulted to COM 3. On my current laptop it defaults to COM 4. You have to change that as necessary in megatune.

 

I try all the com ports 1-7 and do the ecu test. no connection on any.

 

So are you 100% complete on assembly or have you testing the MS as you go as per the PCB assembly instructions?

I remember at the point when you're suppose to test the connectivity in megatune the instructions said that the "test" button doesn't work at that point.

I assume you're using a Serial to USB converter? Drivers installed right?

 

Ive tried it using both a conveter and with out.

My desktop has serial, were as my laptops dont.

Its 100% complete all mods done.

everything went good during assembly, all tests checked out good.

 

well i got it working, had to reflash the firmware.

I loaded up the MSPNP base map, everything looked good.

Had rpm, O2, tps, ait,clt ect from the stim everything looked good there too.

Plug it in the car go to start and nothing, i have no spark.

Ignitor is really hot, so im guessing i fried that some how.


Now with the Stim hooked up have no RPM, everything else is good but i can not get an rpm from it.

Im alittle overwelmed with it right now so im going to bed and will work on it tomarrow.

 

nevermind you answered already

 

It sounds to me like during the time when the MS was not responding to you, the board was powered up but the CPU was inactive owing to the corruption of the firmware.

The nature of the ignition output circuits is such that electrically, they want to be at +5 all the time. The CPU must actively pull them down to 0v by driving a pair of output pins that in turn enable the transistors which are installed between the ignition pullups and ground. Q6 and Q8, specifically.

If the CPU is not up and running, then these transistors are off and the spark outputs both sit at +5. This is precisely what happens during a normal firmware reflash. The CPU stops running the program, clears the existing program, and resets itself. When that happens, all the CPU outputs become inactive, so the spark outputs go high for however long it takes for the CPU to download the new code and then restart. Hence the reason for unplugging the ignition when you load new code.

So yeah, your igniter is probably fried. Sorry.

 

Thing is i reflashed it out of the car using a stum.

I guess i need an ignitor though.


But what would explain the fact that i cant get RPM from the Stim.

 

Do you have both the primary and secondary triggers set up correctly on the Stim? Switches 2 & 3 on, and the "2nd trigger" connected with a wire to I1A on the black screw connector?

Is this a parallel MS? If so, you may need to jumper on the 5v pullups on the Stim. I honestly don't know if Brainey installs those internally on MS's that are intended for parallel operation.

 

the stim i have doesnt have all those things... its like 1.5yrs old i borrowed from a friend. its v2.21 though.

this is a standalone install.. i built it by the mega manaul and did the mods from the megasquirt build thread.

 

Oh, it's not a JimStim...

I honestly don't know if you can run a Miata-configured MS on a regular stim- there's no second trigger signal. Did it work before?

 

worked before doesnt work now.. it makes sense why it shouldnt work.

but it doesnt matter anymore, put ms in the car started it and drove around the block!!!!