How is MS3 going to support the 3 wire PWM idle valves? Is the expansion board going to have a circuit similar to the one offered by Glenn's Garage that actively drives both sides of the valve, or is it still going to require an external fixed resistor to supply a constant load to one side?
I'm really hoping for a 3 wire driver circuit as part of the expansion board.
- Steve
Edit -
Looks like I posted to the wrong area, feel free to tow to General...
3 Wire PWM Idle Valve Support?
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3 Wire PWM Idle Valve Support?
Steve Hauer
http://www.77e21.info
1977 BMW 320i with MAF, COP, IAC, Sequential fuel and spark, MS3 knock sensing
MS3 / MS3X / V3 mainboard, MS3 V1.5 a4
http://www.77e21.info
1977 BMW 320i with MAF, COP, IAC, Sequential fuel and spark, MS3 knock sensing
MS3 / MS3X / V3 mainboard, MS3 V1.5 a4
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Re: 3 Wire PWM Idle Valve Support?
There's no special circuit for 3-wire, we'll just use 2 of the medium current outputs, and drive them opposite to each other in software (using 2 PWM outputs).shauer wrote:How is MS3 going to support the 3 wire PWM idle valves? Is the expansion board going to have a circuit similar to the one offered by Glenn's Garage that actively drives both sides of the valve, or is it still going to require an external fixed resistor to supply a constant load to one side?
I'm really hoping for a 3 wire driver circuit as part of the expansion board.
Ken
Megasquirt is not for use on pollution controlled vehicles. Any advice I give is for off road use only.
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Re: 3 Wire PWM Idle Valve Support?
Sounds great! A software solution to a hardware problem, I like it. Never thought of just driving two PWM outputs opposite each other.muythaibxr wrote: There's no special circuit for 3-wire, we'll just use 2 of the medium current outputs, and drive them opposite to each other in software (using 2 PWM outputs).
Ken
I guess this was posted in the correct section after all.
Thanks
- Steve
Steve Hauer
http://www.77e21.info
1977 BMW 320i with MAF, COP, IAC, Sequential fuel and spark, MS3 knock sensing
MS3 / MS3X / V3 mainboard, MS3 V1.5 a4
http://www.77e21.info
1977 BMW 320i with MAF, COP, IAC, Sequential fuel and spark, MS3 knock sensing
MS3 / MS3X / V3 mainboard, MS3 V1.5 a4
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Re: 3 Wire PWM Idle Valve Support?
Yep, if there's no need for special hardware, then we will avoid having special hardware. That circuit would've been a special circuit specific to idle too. Now we can just use general purpose hardware for the same purpose.
Ken
Ken
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Re: 3 Wire PWM Idle Valve Support?
Sir:
I'd like to know what compiler s being use for S3 development?
I'd like to know what compiler s being use for S3 development?
MSnS'n'4G15
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Re: 3 Wire PWM Idle Valve Support?
gcc.
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Re: 3 Wire PWM Idle Valve Support?
I added the software support for 3 wire a couple of weeks back. I have yet to try it with hardware though!
James
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
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My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".