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

Bad on me but i never did draw up a scmaic, i just design it strait to the pcb layout.  figured i would skip a step to speed up the prosses.
 

but what is on it is basicly 4 MOSFET Drivers, 2 for driving the injectors and 2 for the coils that go to the sparkplugs.

 

has a 4K memory for storing errors/ tunning variabls

 

2 a/d converters,  one is for 0-5 volts the other is 0-2.5

on the 2.5 volt i run:

- 2 temperature sensors, one for manifold air temp the other for engine temp

- O2 sensor input

on the 5V:

- TPS sensor (a pot hooked up to the throttle)

- Map sensor

 

and i have extra inputs for anything i want to add later

use the "poor mans searil in/out [url=http://forums.parallax.com/forums/default.aspx?f=7&m=171998&g=172419#m172419]http://forums.parallax.com/forums/default.aspx?f=7&m=171998&g=172419#m172419[/url]

 

and i have 2 hall sensors, on on the crank and one on the cam

 

i used to voltage reguators,  KA317 to drop it to 8.5 volts , i used that for driving serial port output.  and from 8.5 i use the LM2940 to bring it down to the 5v and before it all thier is a 4001 dioide for protection/help drop the voltage some more.   probably a bad way of doing things but im new at this

 

its still in the building prosses, but i wrote a simple program that gets the engine to run and uses the O2 sensor to set the correct air fuel ratio. this isnt the final program, it still needs alot of work. and features to add to it.   and if thiers any programing sugestions/ enhansments that would be appresated. only been using this stuff for alittle over a month, pretty steep learning curve :shakehead:  

 

 

im not sure if 75 Mhz would be over kill or not but i did run some "benchmarks"  with the chip doing a bunch of calcuations looping, and i figured that 75 would be right, sould beable to handle about 14000 RPM just for running the fuel injectors, perfect for my motocycle :cool:  ,  but this engine its being built for shouldnt run past 5000rpm.   i plan on adding alot more of a load to the prossesor,  haveing it also control the spark advance.  drive a lcd display with the engine temp and rpm  load  etc.  and i also want to be able, while its running, to connect to a computer by serial port so that i can tune it or adjust things while its running.

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