Cheapskates voltage to frequency converter

[gophert]

Also, why does a solar panel voltage need to be read with 3 1/2 digit accuracy (10-bit) or more? What range and accuracy are you measuring? Perhaps a simple voltage shift and attenuation circuit with an op amp could solve your world's problems.

 

[fourtytwo]

No, no. The 16-bit timer/counter is hardware and doesn't rely on code other than to set it up. You can also use the PWM to set the PWM period (not frequency) to nearly any frequency you want as a 16-bit range. You can also slow/speed system clock to increase dynamic range or to tune dynamic range. The PWM period can be set in a buffer register and activated at the next period start so there is no clutch related t code as viewed by the receiver. The max delay of most recently read ADC value until output as a frequency would be a few clock cycles (millionths of a second) and then wait for the current PWM period to finish (about 1/10,000 second).

Yup I must go around that loop again, I think I will have to change the duty cycle reg at the same time as the frequency because I think there based on the same counter but that's still ok just a right shift of frequency to divide by two for duty cycle. May not be very quick as I have a ton of other things to do as well phew!

 

[fourtytwo]

Also, why does a solar panel voltage need to be read with 3 1/2 digit accuracy (10-bit) or more? What range and accuracy are you measuring? Perhaps a simple voltage shift and attenuation circuit with an op amp could solve your world's problems.

Why do people tinker, send things to Mars etc etc I don't know
Seriously though I want a tool to compare panels in the same string and maybe identify problems, ageing, shadowing etc
Stability is probably more important than absolute resolution to <=50mV would be good ( a shade under 10 bit).

 

[Nigel Goodwin]

Why do people tinker, send things to Mars etc etc I don't know
Seriously though I want a tool to compare panels in the same string and maybe identify problems, ageing, shadowing etc
Stability is probably more important than absolute resolution to <=50mV would be good ( a shade under 10 bit).

So your entire system is going to run at an accuracy of 0.1%?

You don't need particularly high accuracy for what you're wanting to do - does it matter if one panel is 0.1% higher output than another?, of course not. I would imagine even 10% accuracy would be plenty for the purpose. Don't forget, dust etc. will alter the output anyway.

 

[fourtytwo]

Also, why does a solar panel voltage need to be read with 3 1/2 digit accuracy (10-bit) or more? What range and accuracy are you measuring? Perhaps a simple voltage shift and attenuation circuit with an op amp could solve your world's problems.

So your entire system is going to run at an accuracy of 0.1%?

You don't need particularly high accuracy for what you're wanting to do - does it matter if one panel is 0.1% higher output than another?, of course not. I would imagine even 10% accuracy would be plenty for the purpose. Don't forget, dust etc. will alter the output anyway.

Well maybe just because I like doing things like that, for the hell of it ok
Anyway this thread does not seem to be about the original subject anymore.

 

[Nigel Goodwin]

So it seems this forum is an expert on other peoples ideas and likes to do them down with every opportunity, well if that's the way you behave just don't bother posting!

BAN me if you like, I don't see the point in being here.

You asked for opinions, you got them - how do you expect to build something with 0.1% accuracy? - are you going to source 0.1% tolerance components?.

 

[crutschow]

So it seems this forum is an expert on other peoples ideas and likes to do them down with every opportunity,

No.
We are trying to understand exactly what you need so we can solve your problem, not solve the solution to your solution.
If you don't like the advice then don't ask for solutions.

 

[gophert]

We are trying to understand exactly what you need so we can solve your problem

crutschow chow That may be a true statement for you and me but not everyone. I asked why 10-bit accuracy is ended,

But Nigel tells him he simply doesn't need to know when he he gets 5 ot 6% shading or his output is dropping and for some reason Nigel thinks monitoring preventive maintenance in 10% increments is what he NEEDs.

You don't need particularly high accuracy for what you're wanting to do - does it matter if one panel is 0.1% higher output than another?, of course not.

I would imagine even 10% accuracy would be plenty for the purpose.

I've never run preventive maintenance with a 10% accuracy. By the time one has a two-data-point-trend, you're at 80% or less efficiency and no time to plan the work or order spare parts. I don't know why our local Samsung TV repairman is making absolute edicts about how someone should tinker wit their solar power systems.
It's so nice Nigel scares new people away. None of those terrible problems to discuss and so much disk space is saved.

 

[fourtytwo]

Well maybe just because I like doing things like that, for the hell of it ok
Anyway this thread does not seem to be about the original subject anymore.