Universal PI Micro

[bugwhiskers]

Schematic

Attached is a brief schematic to show the concept.

regards
bugwhiskers

[bugwhiskers]

Hi Tinkerer,

Have a look at the following link.

http://goldprospecting.invisionplus....t=0&#entry3443

regards
bugwhiskers

[Tinkerer]

New thread

OK, but i dont think this Project is related to Bugwhisker's Universal PI Micro, or is it ?
I spent a long time reading this Thread and it seems like the Universal PI Micro is a finished (and dead) Project.
Bugwhisker's latest Detector is a "secret" Project.

OK, lets make it open Source and please start a new Thread to keep this one free of offtopic Stuff.

I am going to start a new thread "MCU PI Discriminator"

Tinkerer

[Tinkerer]

New Thread

Hi Tinkerer,

If you want to smooth out noise from the ADC readings you can try the following method.

Create a string of locations in RAM, maybe 64
Have a routine that shifts them all along one position each cycle, loses the oldest and puts the latest reading in the first position.

Each cycle add them all up then divide by 64 (shift right 6 times) voila, a software integrator.
If you have 10000 cycles per second then the time lag wrought by the averaging will be minimal.

No signal strength will be lost, just noise.

Prevention is better than cure. Make sure your PCB has an effective ground plane and all the components associated with the front end are grounded as near as possible to the same point. The + of the tank cap is a good spot.

regards
bugwhiskers

Thanks for your help Bugwhiskers.

This is certainly very good advice.

I am going to start a new thread as Gotz suggests. We would very much welcome your input also in the new thread.

Tinkerer

[bugwhiskers]

Hi Tinkerer,

If you want to smooth out noise from the ADC readings you can try the following method.

Create a string of locations in RAM, maybe 64
Have a routine that shifts them all along one position each cycle, loses the oldest and puts the latest reading in the first position.

Each cycle add them all up then divide by 64 (shift right 6 times) voila, a software integrator.
If you have 10000 cycles per second then the time lag wrought by the averaging will be minimal.

No signal strength will be lost, just noise.

Prevention is better than cure. Make sure your PCB has an effective ground plane and all the components associated with the front end are grounded as near as possible to the same point. The + of the tank cap is a good spot.

regards
bugwhiskers

[Götz von Berlichingen]

Carl has kept this forum going for ten years.
We all should show our gratitude by posting interesting subjects.
So I propose we make this an "Open source" project.
At least the "demo" mode.
Tinkerer

OK, but i dont think this Project is related to Bugwhisker's Universal PI Micro, or is it ?
I spent a long time reading this Thread and it seems like the Universal PI Micro is a finished (and dead) Project.
Bugwhisker's latest Detector is a "secret" Project.

OK, lets make it open Source and please start a new Thread to keep this one free of offtopic Stuff.

[Tinkerer]

Discriminating PI project

Your discriminating PI ? Is this Project here on Geotech ?
I will be busy the next few Days, have Work to do.
I'm not a great Programmer, but willing to help and
i have a few 877 and 877a for testing.
What exactly should the Program do ?
Is this Thread the proper Place to discuss it,
or should we take it to Private Messages or a new Thread ?

Carl has kept this forum going for ten years.
We all should show our gratitude by posting interesting subjects.
So I propose we make this an "Open source" project.
At least the "demo" mode.
Tinkerer

[Götz von Berlichingen]

Gotz Von Berlichingen,

Do you feel like trying your hand at writing some code for my discriminating PI?
I have a PIC 16F690 and a PIC 16F877 and programming and debugging capability for them.

I have also downloaded the AVR Studio to have a look at it for future applications.

Tinkerer

Your discriminating PI ? Is this Project here on Geotech ?
I will be busy the next few Days, have Work to do.
I'm not a great Programmer, but willing to help and
i have a few 877 and 877a for testing.
What exactly should the Program do ?
Is this Thread the proper Place to discuss it,
or should we take it to Private Messages or a new Thread ?

[Tinkerer]

PIC or AVR

Gotz Von Berlichingen,

Do you feel like trying your hand at writing some code for my discriminating PI?
I have a PIC 16F690 and a PIC 16F877 and programming and debugging capability for them.

I have also downloaded the AVR Studio to have a look at it for future applications.

Tinkerer

[Tinkerer]

PIC or AVR?

Well, i learned about PICs first, got some free samples from Microchip
and learned to use them.
Now I'm too lazy to learn about AVRs.
There could be one Reason to use Atmel Products :
there is an open source USB Stack, no special Hardware needed... cool.
I found nothing like this for PIC - and the USB-PICs are not cheap.
Oh, and the 1 Instruction / clock cycle thing *sigh*
as far as i know, even the PIC18 need 4 clock cycles for 1 instruction.
Well, until now i needed no USB and PICs were fast enough for me.

My next Project : a stuart2 PI... first the Original, later some extra Stuff.
One or more S&H Circuits (somehow like Bugwhisker's old Design)
and the PICs A/D (10Bit) might be worth trying.

Thanks for the explanation. This really makes sense. I will stick to the PIC for this project, but will be looking around for the next project.
As for the the writing of code? I make myself no illusions. I can manage some very simple stuff but for more advanced code I will need help.

Tinkerer

[Götz von Berlichingen]

Thanks for the input.
I believe both are good. It is probably a matter of personal preference.

Would you be so kind to explain the reasons WHY you prefer PIC's?

Tinkerer

Well, i learned about PICs first, got some free samples from Microchip
and learned to use them.
Now I'm too lazy to learn about AVRs.
There could be one Reason to use Atmel Products :
there is an open source USB Stack, no special Hardware needed... cool.
I found nothing like this for PIC - and the USB-PICs are not cheap.
Oh, and the 1 Instruction / clock cycle thing *sigh*
as far as i know, even the PIC18 need 4 clock cycles for 1 instruction.
Well, until now i needed no USB and PICs were fast enough for me.

My next Project : a stuart2 PI... first the Original, later some extra Stuff.
One or more S&H Circuits (somehow like Bugwhisker's old Design)
and the PICs A/D (10Bit) might be worth trying.

[Tinkerer]

AVR or PIC?

*stands up and waves a Microchip flag*

Honestly, i heard Atmel Stuff is not bad.
Use whatever you like, I prefer PICs and HiTech-C.

Thanks for the input.
I believe both are good. It is probably a matter of personal preference.

Would you be so kind to explain the reasons WHY you prefer PIC's?

Tinkerer

[Götz von Berlichingen]

Bugwhiskers and Aziz, thanks for the recommendations.

Will anybody stand up and defend the PIC?

Tinkerer

*stands up and waves a Microchip flag*

Honestly, i heard Atmel Stuff is not bad.
Use whatever you like, I prefer PICs and HiTech-C.

[Tinkerer]

AVR or PIC?

Bugwhiskers and Aziz, thanks for the recommendations.

Will anybody stand up and defend the PIC?

Tinkerer

[Aziz]

I can not recommend the PIC µC family. Particularly the paging on the PIC is quite inefficient. To avoid this, use only PIC18, PIC24 or dsPIC. The latter have a linear memory architecture.

If you want to use a real RISC µC, use the Atmel ones. They are darn cheap and easy to get. They have a better computation power (four times better than on a PIC with equal clock frequency).

To ensure better and accurate timings, use only a stabilized external crystal oscillator. Do not use the internal RC oscillator of the µC.

Aziz