trigger preparations for v3.1
While v2.2 was running the engine (fuel only), we took a PC scope and a v3.1 (with Alubos and lotsof wires) to check the signals from the distributor. The signals were as we thought:
- GND
- 12V
- 5V trigger for every event (4 camtooth: coil-type if you like)
- 5V trigger 1 per engine cycle (1 camtooth)
![[a scope snapshot]](http://www.vems.hu/files/Fero/Mazda_cam_trigger.JPG){kind=link}
notes:
- 1/10 probe was used, so grid is 1V (not 0.1V)
- the scope captured the very last tooth for the yellow signal (the 1 camtooth HALLsignal) when the probe was disconnected. The 4 tooth signal continued for a while. During normal operation the frequency of the green was exactly 4* times that of yellow.
On the picture, green duty is about (12msec / 32 msec)
When RPM was about 1500,
- the green duty was 7.5 msec and period 20 msec
- the yellow period was 80 msec
We attached the v3.1 LM1815 input (through a 10uF 35V 1210 cap, that was on its place on the bottom side of board) to the 4-tooth signal, and read the correct RPM value (after enabling the primary_trigger).