== Trigger: div-by-43 ==

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* Pinout:

** speed sensor signal (129 teeth per crank rev) to Pin 27 (Eco36)

** speed sensor ground to Pin 26 (Eco36)

** reference sensor ground (1 tooth per crank rev) to Pin 12 (Eco18)

** reference sensor signal to Pin 26 (Eco36)

*** (reference sensor has swapped lines due to AUDI setup)

** Pin 13 (Eco36) grounded (same ground like Pin26)

* Actual trigger setting <- not recommended by support but works !!!

** Number of cylinders = 6

** Audi trigger divider = 43

** TDC after the trigger = 50.0

** Number of Teeth On Wheel = 6

** # of teeth of full engine cycle = 6

** First trigger tooth = 0

** Next trigger tooth = 1

** Angular Width of Tooth = 120 degrees

** Reference trigger tooth table = 0, 5, 4, 3, 2, 1

** This looks very nice in VEMSTune Trigger Settings Visual

*** engine runs with that , any downsides ???

*** masking the sectrig to only consider every second pulse ???

**

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Additional Information by support team:

* primary trigger: 129 is 43*3

** that is 43 per event: 43 is a prime number so cannot be divided. Therefore divide by 43 is the way to go with this trigger: the only way

** 129 means 258 for a full engine cycle, the max value for "Coil-type" + "normal" is 255 !

*** using a divider is a must anyway, because only that allows a race-condition between secondary trigger and primary trigger, should the 2 falling edges of primtrig-VR and sectrig-VR be close

** timing from 3 pulses means that (crankhome-VR) pulse must be 35-75 crankdeg BTDC.

** Also, during cranking, relative angular acceleration is high (does not double, but RPM * 1.3 is possible) between consecutive events, so, as a result the actual spark will be slightly delayed during cranking when the engine suddenly comes alive

*** this can be somewhat compensated with a few degrees higher sparkadv at 400 RPM. Does not effect normal running (even quick acceleration in gear1).

** if really 129, than 43 tooth per event per (if 6cyl). But with divby3 (and 43 tooth total,) next_trigger_tooth=14, 14*3=42 tooth (~2.75 degree percylinder spark delay) can be used to compensate this tooth...

** important: divby4 (11*4=44) is clearly invalid, there is no integer T=tooth_count for which 4 * T = 129 so trigger error would always be on with that (if it would run at all)

** So I need to use "Auditrigger DivbyN" option and a "Audi trigger divider" of 43.

***So number of teeth on wheel becomes 3 (carrying over what I see on the AUDI configs) confirmed!

*** First trigger tooth = 0

*** Next trigger tooth = 1

*** Angular width of teeth = 120°

Good spark events with this c129 trigger (because of divby43, only 3 primtrig shown in triggerlog between sectrig pulses, not 129):

How it was made

* The "nr of cylinders" is only used by the ECU for the RPM calculation.

** For 6 cyl, normally 6 cyl must be configured (when 1 sectrig pulse every cam rotation). Possible with same primtrig setup, using "c258" trigger: that means using third (cam-HALL ) sensor masking out every 2nd pulse

** Since for the c129 trigger there is 1 sectrig pulse every crank rotation, in this case, "3 cyl" must be configured. (of course 6 injector outputs can be used).

** minimum 3 ignouts must be configured, even if all are the same (eg. when using distributer)

*** MacB: RPMs are doubled with this setup, i use the setup on top of the page and get the same output in triggerlog with correct calculated RPMs !

[more comments, and config]

To adjust and verify "TDC after the trigger" setting, of course it's always good to verify actual spark-timing with strobelight, using 2 different sparkangle (eg. 2 deg and 18 deg).

* MacB: VERIFIED !

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