Hi,
I am new to Engines as I basically took electronics engineering. I have a project to design a ECU for small engines (35cc). I am planning to use ARM-Cortex-M4 based controller @ 80Mhz. The problem is, I am not clear about stuff like volumetric efficiency etc etc. All I know is that Sensors are interfaced to the controller which modulates the pulse to the fuel injector which injects the fuel.
I now wanted to know how to program the fuel maps into the controller. I mean how do you accomplish that? I browsed the forum and found a guy used formula based approach of real time estimation of amount of fuel to be injected (with parallex controller). My concern is that, is this approach reliable? and also, I feel that at 80Mhz, the controller can outsmart the engine at real time computations. Can anyone kindly guide me?
Thanks.
Help regarding programming ECU.
Re: Help regarding programming ECU.
For a single cylinder, that MCU should be a nice choice.
Don't use formulas, use tables. Give yourself a way to edit the tables live.
Does it have an FPU? If so, the math will be trivial.
Don't forget ignition.
Fred.
Don't use formulas, use tables. Give yourself a way to edit the tables live.
Does it have an FPU? If so, the math will be trivial.
Don't forget ignition.
Fred.
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Re: Help regarding programming ECU.
Hi fred,
thanks for your reply.
yes the mcu has a fpu. so, can i use the formula approach?
I just learned about the tables... but have no idea how to program them. I mean how to place the table in the memory such thing. I assume arrays (2d) are used to hold the value, and conditional statements are used to look for particular spot on the table. Am I correct?
thanks for your reply.
yes the mcu has a fpu. so, can i use the formula approach?
I just learned about the tables... but have no idea how to program them. I mean how to place the table in the memory such thing. I assume arrays (2d) are used to hold the value, and conditional statements are used to look for particular spot on the table. Am I correct?
Re: Help regarding programming ECU.
Something like that, sort of, yes :-)
Get your hands dirty, it's the best way!
Fred.
Get your hands dirty, it's the best way!
Fred.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
Re: Help regarding programming ECU.
Hi Fred,
Thankyou, I ll post the progressof my project. By the way, why is not this forum accessible by tapatalk?
Thanks.
Thankyou, I ll post the progressof my project. By the way, why is not this forum accessible by tapatalk?
Thanks.
Re: Help regarding programming ECU.
It requires a plugin. I don't have time for that. Use a computer ;-)
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
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FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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Re: Help regarding programming ECU.
I am also playing with an ARM-based ECU so you might want to have a glance at my code for table lookup, it even has unit tests & interpolation:Anish wrote:but have no idea how to program them. I mean how to place the table in the memory such thing. I assume arrays (2d) are used to hold the value, and conditional statements are used to look for particular spot on the table. Am I correct?
http://sourceforge.net/p/rusefi/code/HE ... polation.c