Coil states on first energizing?

[E4ODnut]

I have an MS1 V2.2 board with the latest MSnSExtra firmware. I've got it configured to run a 4 cyl, 4 stroke, even firing engine with waste spark and batch alternating injection. I'm doing some bench testing on a simulator to make sure it's doing what I want it to do before actually committing it to the engine. I have a 36-1 wheel mounted on my wood router with a VR sensor and Jean's dual output VR board V2.1. I have test points on the MS board so I can use a digital signal analyzer to check all the relevant pin states and their relationship to each other. For the most part things are behaving they way I thought they should but there is one interesting wrinkle.
When MS is first energized PTC0 (coilA), PTC1 (coilB), PTD4 (Inj1), PTD5 (Inj2) and PTA2 (Tachout) all go high. They stay high for 0.45 seconds then they all go low. PTA0 (FP) goes high. PTD4 and PTD5 stay low for the appropriate prime pulse time, then go high again. PTA0 stays high for 2.5 seconds then goes low. The pin states stay this way until the crank sensor signals start and synch is established. At that time PTA0 goes high again, and the other pins behave as they should.
My concern is the initial behavior of the coil pins. It looks to me like they would energize the coils for a dwell time of 0.45 seconds and then fire the coils. This might not do any harm, but if there is fuel available it might not be a good thing.
Is this normal?

[Matt Cramer]

This is normal; the recommended work-around on MS1s is to power the coil from the fuel pump relay to delay energizing the coil.

[E4ODnut]

Hi Matt,
Thanks so much for the reply. I am supplying power to the coils, injectors, IAC valve, tach out signal and EGO controller through the fuel pump relay, so it looks like the boot up condition wouldn't have been a problem after all. I should have thought of that. At this point I'm just testing the 5 volt signals. I should be able to prove this when I test the 12 volt ones.

[E4ODnut]

It looks like I have another issue.

I completed the simulator with pots for the ADC inputs, a muffin fan to simulate the fuel pump, 4 actual injectors and a coil pack with spark plugs. I can check the actual timing against the commanded timing with a timing light on the trigger wheel. The first thing I noticed is that the injectors were pulsing rapidly for a moment as the wheel got up to speed. I disconnected the coil pack and injectors just to make sure it wasn't a noise issue or something like that and went back to analyze the 5 volt signals. What I am seeing is that as the wheel begins to turn I get several quick pulses on the injectors beyond the prime pulse. I also get several premature spark events with very long dwell times. The quicker I can get the wheel turning the less the problem seems to be. I tried holding the wheel back so it turns quite slowly and it looks like I am getting injector pulses on every tooth event and some very long dwell period spark events where they are not supposed to be. At crank speeds above about 82 RPM everything looks relatively normal. The signal from the VR conditioner is a perfect wave form showing the missing tooth and the wave form from the IRQ is a perfect inverted mirror of the VR signal. Is there a bug in the firmware?

[jsmcortina]

Is there a bug in the firmware?

If there is, it isn't going to be looked at. MS1 maintenance ended over a decade ago.

James

[E4ODnut]

Thanks for the help.