DIYEFI.org Forum

From a decoder perspective we have three main cases:

• Per cylinder (usually cam based)
• Per revolution (crank based)
• Per cycle (usually cam based)

For two-stroke use per-cycle is also per-revolution and crank based with a full pattern of 360 degrees. That is to say, the per-cycle 720 degree decoder setups are not used on 2 strokes.

Per cylinder, aka, distributor style patterns could be generated from the crank just as much as the cam, if not for the distribution of spark issue. On a two-stroke per-cylinder could only be done from the crank.

So, then, the following cases exist:

1. Four stroke, cam sync signal, 720 cycle
2. Four stroke, crank sync signal, 360 cycle repeated twice
3. Four stroke, per-cylinder sync signal, 720/cyl-count cycle, repeated cyl-count times
4. Two stroke, crank sync signal, 360 cycle
5. Two stroke, per-cylinder signal, 360/cyl-count cycle, repeated cyl-count times
6. Wankel, "crank" sync signal, 360 cycle
7. Wankel, per-combustion signal, 360/rotor-count cycle, repeated rotor-count times

Currently the scheduler uses a 720 pattern to do its math even for a sub-720 decoder. I may need to change this to simplify 2 stroke and rotor use.

Fred.

Did I miss anything? Is anything wrong? Thanks for confirming and/or denying!

Fred.

I always thought of it like this for general pondering:
A cam sync signal on a four-stroke = a crank sync signal on a two-stroke.

"Currently the scheduler uses a 720 pattern to do its math even for a sub-720 decoder. I may need to change this to simplify 2 stroke and rotor use."
Cant you just multiply the *movent and keep the same back-end logic?

-sean