In SX Microcontrollers, SX/B Compiler and SX-Key Tool, markistuff wrote:

I have been busy the last few days working on other projects that have higher prioity, like reroofing, and building a fence, etc.   All the input and comments everyone has are great.  hope all this info that has all been bought together can helpout others oneday who want to tackle a simlare project.   
 

i took the buddie out for a little test drive up and down the block.   thier are a few things that i have to work out.  i found out that the VE is alot differnt when the engine is under load verses no load.   so i need to reprogram that.  and my throttle body really didnt work to well. tryed to build one but it lets it idle way to high, so i got a good throttle body and need to hook it up.  then thier are a few things i need to program into the code.  

 

GAF - im not sure if im doing the right equations to calculate out the pulse width.  when i was writing them up i noticed that the rpm was cancled out, so i just left it out.  hopefully that dosnt cause to many problems.

 

Air Density (kg/m[4]³[/4]) = 1000 * MAP(KPA) / 287 * TEMP(K) 

 

Pulse Width (ms) = AirDensity(Kg/m[4]³[/4]) * Displacment(m[4]³[/4])/2 * Ratio(fuel / air) * InjectorFlowRate(ms/Kg) * VE  + Injector Opening Time(1 ms) + Accelorator Enriching.

for the accelorator enriching.  i have the sx read the value of the tps and store it.  then next time round it reads the new tps value and tackes the differnece, only for opening, and mulitplys it by a constent to give me how many ms pulse width to add to make it have no hesitation.

 

I'll try restricting the opening to the MAP sensor see if that helps smooth things out.

I've been trying to write an equation to figure out the VE.  i wrote one but it applies to when the engine has no load on it.  when a load is attached it requiires alot more fuel.  before i had the VE porportate only to the RPM,  but when i get some time ill do some testing and figure one out to give me the VE in relation to the MAP reading and RPM.   the engin is very inefficent. its a old flat head horizontaly opposed kohler.  its only supost to run to 3600 but it runs safe up to 4000 rpm.  but the reason for such high MHz is i want this project to beable to be used on a motocycle engin eventualy that goes up to 14000 rpm.  the buggie is my testing grounds for projects.

 

i attached the last version i made of the program. its very messy and i havent done any of the fixes i mentioned earlyer.  probable wont get around to it for a few days.  going camping this weekend.  but the engine sure starts up great.  before i used to have to crank the engine for about 30 seconds with the choke on before it would fire up and stay running. now just bairly hit the starter and it fires right up.

   

BTW, i havent started school yet.  i plan on going to a tech school in september for electrical engineering.  i figured this project would get my "feet wet" in what i want to be doing.

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