No, that is fine. The more eyes and comments, the better IMO.
This is a Saab DI cassette (CDI - COP ) unit. It requires a funky signal to run the spark unit. It charges the capacitor by keeping the line high then discharges at the spark event by pulling the line low for 0.5ms or more. To get a hot spark, I have been using 1ms which allows the CDI time to charge within my rev range and can ignite a very wet mixture at high boost (at least with MS1/E). I have been having problems with the 'time after spark' setting in MS2/E and wanted to do an even comparison for James and Ken to help them diagnose what may be going on.
I can muddle around with the code in the MS1/E asm, but it will take me a while to get a handle on the MS2/E C code...
Keithg wrote:The kids are in bed and the scope is warmed up. Flat lines means it goes to 0V on the output.
MS2/E 20070701
Configured as 'basic trigger' with time after set to 1.0 ms it measures 0.7ms (on my scope) and is very steady. It flat lines at 8500 rpm. 2ms measures 1.4ms and flat lines at 4300 rpm. 2.2ms yields the same trigger time I get with MS1/E, and it goes flat at 3500 rpm. I cannot run more than the one output as I do not have a JimStim.
MS2/E 20070706b and 20070708
Woah! time after spark does not appear to work in these versions. The waveform is inverted and it appears to be normal dwell. The time spent at 0V varies throughout the RPM range. I reverted to 20070701 and all appears well again, so neither of these versions appear to work with 'time after' dwell.
MS1/E HR09C
Configured as 4 spark outputs with stim for wheel. The code 'should' give 1ms, but my scope measures it as 1.6ms. When I reduce the spark outputs to 1, I get the same thing... Ditto when I set it as MSnS mode with spark A only. At 13krpm, the time it is pulled down to 0V lengthens by 0.1ms to 1.7ms.
I believe the problems I am having with 20070701 is due to the fact that I cannot run enough duration and get it to go through 3500 rpm. With short duration (0.2ms) I get weak spark which causes misfire under load and when I get enough duration to have decent idle, I get an undesired rev limiter. The other 2 versions I have not loaded in the car, but from the spark trigger waveform, it does not appear that they will appropriately drive the CDI unit.
KeithG
Keith, nothing has changed between those versions as far as the spark mode you use goes. I would expect something else to be causing the problem, but will check tonight anyway.
The battery correction *may* be affecting it, so just disable that correction.
I guessed as much which was why I was so surprised that it was different. I loaded it again then back to 20070701 just to make sure I was not seeing something. Each time, I loaded the firmware onto the MS2, then loaded my MSQ then set trigger to basic to see what the spark output was doing.
KeithG
Keith, nothing has changed between those versions as far as the spark mode you use goes. I would expect something else to be causing the problem, but will check tonight anyway.
I guessed as much which was why I was so surprised that it was different. I loaded it again then back to 20070701 just to make sure I was not seeing something. Each time, I loaded the firmware onto the MS2, then loaded my MSQ then set trigger to basic to see what the spark output was doing.
KeithG
Keith, nothing has changed between those versions as far as the spark mode you use goes. I would expect something else to be causing the problem, but will check tonight anyway.
Ken
Keith, the only problem I found was that the ini file was not scaling the time after spark number properly. I fixed that and it matches what's set perfectly.
Gokart wrote:Beta 4;
It seems that rev limiter will not do the fuel cut. Only spark cut. Even choosing 'fuel and spark cut' will only have the spark cut out but not the injection. There will be no limit if we choose fuel cut only.
I did this on the JimStim and hope that someone else will confirm the behaviour.
EDIT: I just tried all the options, and they all work, including fuel cut.
