TZR250 3MA
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Finally I had time to start on my little Electronic corner. (its not ready yet but its a start)
Building my own dyno took almost a year off my projects and the workshop was a mess.
So I'm very happy that its ready, slowly starting up many off my ideas&planes from the past year.
One off them is measuring more signals from the CDI in order to understand it better.
Here you have my starting point.
Two small tool boxes are there to store the parts.
One serves as a holder for measuring devises
More will come in the future, as the build continuous.
My quick setup is as followed

1) 12V power supply connected to the CDI
2) Pulse generator generator a pickup pulse
3) Oscilloscope measuring pins to measure the signals

Easy and works very well
Here you have the speedlimiter signal
1) Yellow is the close signal (lower the exhaust valve)
2) Blue is open signal (exhaust valve in the fully open position)

This image is created by swishing between 360Hz and 370Hz
360Hz is 10800rpm (limiter not active)
370Hz is 11100rpm (limiter is active)
Here you see it in action, me giving the limiter signal
These control pulses coming from Pin 5 and 6 (at the IC)

To Pin 1 and 2 from the TA8050P (servo driver)

The length off the pulses seems to be the control point for the TA8050P
As you can see open and close is the same pulse as the exhaust valve needs to be at the same position
The TA8050P seems to work as followed
Pin 1 and 2 (pulses from the IC)
Pin 3 and 5 (control servo motor)
Pin 4 Ground
Pin 6 Open
Pin 7 (5V internal IC control)
After quit some measurements, my conclusion is as followed

The length off the pulses given on pin 5 and 6 depends on the voltage read on pin 36 at the IC (YPVS sensor)

At a certain rpm belongs a certain ypvs opening.
When for example at 7800rpm it needs a 48% opening that will be 1,68V at pin 36 on the IC
Pin 5 will give a certain pulse long enough to drive the YPVS motor to the point where the ypvs sensor says 1,68V then it will stop.
Because they are all small step so are the pulses.

Only the speed limiter pulse is somewhat long, but that is logical as it needs to turn the exhaust valve quit a bid.
Sadly I can't find anything to bypass the CDI at the IC (Have ordered a 3MA SUGO CDI for measurements)

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