MCU Choice

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mobyfab
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Re: MCU Choice

Post by mobyfab »

I was wondering why you picked it in the first place actually.

For the 3.3v, most chips are 5v tolerant on nearly all their pins. This is the standard nowadays.

What I mean by starting fresh is that I'm still evaluating options, I could start from scratch if I don't find anything that suits my needs. Else I would help with an ongoing project.

Fabien.
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Fred
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Re: MCU Choice

Post by Fred »

mobyfab wrote:I was wondering why you picked it in the first place actually.
OK :-)
For the 3.3v, most chips are 5v tolerant on nearly all their pins. This is the standard nowadays.
ADCs? That's the main one.
What I mean by starting fresh is that I'm still evaluating options, I could start from scratch if I don't find anything that suits my needs
What exactly are your needs?
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mobyfab
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Re: MCU Choice

Post by mobyfab »

ADC is not a real problem since you can use 3.3v as a reference instead.

Or do something like analog multiplexer -> voltage divider -> (opamp to reduce resistance / protect ADC) -> ADC if you really need a 5v or higher source.

I need a common 32bits MCU, Arm would be the best.
The goal is to make a standalone ECU for race motorcycles, so basically 8 injectors (staging), 4 ignitions drivers and knock detection.
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Fred
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Re: MCU Choice

Post by Fred »

mobyfab wrote:voltage divider -> (opamp to reduce resistance / protect ADC) -> ADC if you really need a 5v or higher source.
I guess that's OK with high precision resistors.
The goal is to make a standalone ECU for race motorcycles, so basically 8 injectors (staging), 4 ignitions drivers and knock detection.
Too easy :-)
I need a common 32bits MCU, Arm would be the best.
Wait, is that need related to the above goal? Or just a desire? ;-)

I look forward to hearing about your progress.

Fred.
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mobyfab
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Re: MCU Choice

Post by mobyfab »

I could use any MCU that suits the requirements, it's just that I'm used to ARM (more precisely STM32, which are the most common CM3s) and everything that comes with it (tools), so it's easier.
Also I want to use the most common components I can to make it easy/cheap to build. (still gonna be SMD, but reflow it not that hard)
The ultimate goal is to make a generic board, and an I/O board that's made to be compliant with the original MCU pinout/connectors/sensors.

It's not so much the hardware that's complicated, as you know :)
I already have a clear picture of what I need on the board.

You can add traction control, quick-shifter, exhaust valve control, wideband & thermocouple controller to the above requirements :)
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Fred
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Re: MCU Choice

Post by Fred »

Yes, I know it well ;-)

It goes like this:

Hardware < Software < Firmware < Community.

I'm looking to build the latter around the one before it, which then spawns the other two. This is the challenge and it's much much bigger than one little forum can hope to convey.

Fred.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
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n00bs, do NOT PM or email tech questions! Use the forum!
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