Arduino Nano PI Main Discussion

[green]

Originally Posted by green


I wonder why we can't set a goal and then define what might be required to accomplish the goal. Do we need GEB? Is #4 lead shot a good test target? What distance do we want to detect the test target(GEB on and GEB off)?

If we need GEB, there is going to be a hole. Where would we like it?




Thanks Again

What I'm doing today, maybe different tomorrow.
Tx time, 160us
Tx rate, 1000pps unipolar, 2000pps bipolar
target delay time, adjustable front panel(3.5us to 20us)
target sample time, adjustable front panel(5us to 20us)also used to adjust GB, needs fine adjust
GEB, front panel on-off
ground delay time, 4us haven't played much with different times
ground sample time, 100us
Open to suggestions to make it better. Never learned micro's so can't help with programing. Still need to define control loop whether it's done with logic or micro.

unipolar needs an EF sample also

[Qiaozhi]

I'm still in my infancy of trying to functionally understand code but I found this tread on the arduino forum that mentions using the Millis command instead of the delay command to seemingly perform two functions at once.

This is the thread.

https://forum.arduino.cc/index.php?topic=503368.0

Not knowing all the pitfalls of programming and trying to learn still.
I wanted to ask (before I went down a long wrong road ) if you thought this was a viable method of possibly speeding the code?

There would probably be even more delay introduced by using the millis() function.

If I wanted to create a shorter main sample delay, I would combine state 1 and 2 of the interrupt state machine and create the delay by invoking the NOP command a few times via an assembler call.
For example: "__asm__ __volatile__ ("nop\n\t");".

I think that this single instruction will introduce a delay of 62.5ns, but I would have to test it to be certain. Try adding a for loop around the asm call in your sketch and measure the delay on the scope.

[godigit1]

Going back to the Nannos That dont work.

I ordered three elegoos and they booted right up One avr dude did not.
The fix was to load the old bootloader under tools, Processor .

This may not be the solution for all the boards but at least worth a try.

[godigit1]

Originally Posted by green
surfdetector has a kit completed on the bench. Maybe he could try to detect a piece of #4 lead shot if #4 shot is a good test target.

I wonder why we can't set a goal and then define what might be required to accomplish the goal. Do we need GEB? Is #4 lead shot a good test target? What distance do we want to detect the test target(GEB on and GEB off)?

If we need GEB, there is going to be a hole. Where would we like it?



#4 lead shot has a diameter of 3.1mm, so from calculation:

[IMG]https://www.geotech1.com/cgi-bin/mimetex.cgi?\tau%20=%20\frac{\mu%20a^2%20\sigma}{\ pi^2}\%20=\%20\frac{(4\pi%20*%2010^{-7})\%20%20*\%20%20(1.55%20*%2010^{-3})^2\%20*\%20(4.55*10^6)}{\pi^2}\%20=\%201.39\mu% 20s[/IMG]

in this case the current implementation of the Arduino Nano detector should not be able to detect #4 lead shot. This is because the minimum main sample delay is 10us. Since 5 * 1.39us = 6.95us, the eddy currents will have died away long before the main sample occurs. The 10us minimum delay is caused by the software overhead due to setting up the timer register and entering and exiting the interrupt routine. However it should be possible to get below 10us if the delay is produced without relying on the timer. Of course this would still require a suitable coil, and possibly a reduction in the TX pulse width.

The actual position of the target hole will depend somewhat on the soil conditions, and consequently the TC you're trying to ignore.

Is #4 lead shot a realistic target to use for testing?
Carl has previously said: "If you can detect a #9 lead shot, then you can detect most 1/2 grain nuggets".
Calculating the tau of #9 lead shot gives 579ns. Which means that the eddy currents have vanished after only 2.9us.

Hi Qiaozhi,

From this post in extra extra Deep detector thread Min 1st sample delay is currently set to 10 us due to the interrupt routines.

I'm still in my infancy of trying to functionally understand code but I found this tread on the arduino forum that mentions using the Millis command instead of the delay command to seemingly perform two functions at once.


This is the thread.

https://forum.arduino.cc/index.php?topic=503368.0

Not knowing all the pitfalls of programming and trying to learn still.
I wanted to ask (before I went down a long wrong road ) if you thought this was a viable method of possibly speeding the code?


My first goal would to be able to get the Arduino Pi code first sample spacing to 5 us or at least 7 or 8 would be a good #.
This would make the mods made to Pro Q front end even worth while and from there I can start working in the Gb to the code Or maybe Ill have to bribe somebody.

As far as booting from a Sd Card in the field, Ive found three ways to do that but need to pull the trigger on what Sd card or data logger I want to try.

I was glad to see green and you all talking about a arduino based gold detector as that wasn't really my intention here.
I was just wanting more of a learning platform mainly for the coding end with a simple GB.

Would love to see a arduino conversion of something like the GS 4 That would be fun..

Thanks Again

[MartyJ1963]

Hi Martin, I have their Website bookmarked because there's loads of good stuff on their site, Handy for the future. Regards, Marty.

[godigit1]

I finally finished with my Pcb and ordered boards from JlC .
Wow it was super easy. And the price cant be beat in the Us or come anywhere close.
I ordered 5 arduino Pi boards and 5 proto Pro Qs for less than the price of one board locally. And even with two ounce copper.
Yea won't be etching any of my own boards anymore.

Here is the gerber for the Arduino pi pro Q board. any critiquing would be welcome.

arduino Pi Pro Q revA.zip


Some of the forum members have mentioned the pain of routing a 4066 now I know what there talking about especially with the jumpers I added.
This will be a fun project for me having both boards to build at the same time Ill be able to see the exact results of the changes I made for good or bad
Ill post the proto build as I go.
Thanks again for all the help.

[MartinB]

Just waiting on a few components to start building. They should arrive tomorrow. Regards, Marty

Hi Marty
I always use this company for my Arduinos Arduino (hobbycomponents.com)
My parts don't arrive until Tuesday because it is Easter

[MartyJ1963]

Just waiting on a few components to start building. They should arrive tomorrow. Regards, Marty

[6666]

Hi Bruce, Do you mean Arduino software? The software I used was Arduino 1.8.13. Is that what you meant? Regards, Marty.

Thanks, yes thats it.

[MartyJ1963]

Hi Bruce, Do you mean Arduino software? The software I used was Arduino 1.8.13. Is that what you meant? Regards, Marty.

[lc516]

I am one that has experimented with digitizing the decay curve. Used the front end of my HammerHead2 and a PIC32 processor. I did an exponential curve fit to obtain a TC. This worked fairly well for well defined non-ferrous targets like coins but odd shaped targets and iron gave odd results, TC could be anything so really did not discriminate ferrous/nonferrous.
I never wrote this up and posted on Geotech but did write up some of the PIC32 code methods used to generate signals.
Once I get some time I would like to revisit this with the VooDoo circuit that has ferrous discrimination.

Maybe,you can add a ADC Pin input the nano,run your code with this circuit.
Just on TP6 point to ADC Pin,than the PI had a new feature.

[6666]

Thanks Marty, which IDE version are you using ?

[MartyJ1963]

Hiya All, I had a few problems trying to upload the 'Arduino PI' INO code to my new Nano's. Firstly, the Nano's I bought are not genuine ones. The onboard chip is the CH340G. I use Windows 7 64-bit. Here is the link for the Nano's I ordered https://www.ebay.co.uk/itm/New-Nano-...r/313074662903. I downloaded a Windows CH340 Driver from this link https://www.arduined.eu/ch340g-conve...iver-download/. I used the normal settings etc to upload the code but with no success. I then changed a few settings and finally got both of my new Non-Genuine Nano's to program correctly. 1. Select 'Tools' in the Arduino Taskbar then 'Board'. Select 'Arduino Nano'. 2. Select 'Tools' then 'Processor' then 'Atmega328P (Old Bootloader). 3. Select 'Tools' then 'Programmer' then 'Arduino as ISP'. These settings for me resulted in success. The link above for the Nano's are pretty cheap too! I just thought I'd provide the steps I used in case anyone else was having trouble programming their clone Nano's. Hope everyone has a successful build with this new exciting project kindly provided 'again' for free by George. Thanks George! Regards, Marty.

[Qiaozhi]

[QUOTE = Xtrem; 286960]这是一个不错的项目，尤其是对于学习和教育而言，但是让我对
电路进行一些更改。

[ATTACH] 54816 [/ ATTACH] [/ QUOTE]
That's looks more concisely.
Is it have same sensitivity with original design?

In fact the sensitivity is better than the original. The Nano controls the TX oscillator, sample pulses, and generates the audio tone. Since the TX pulse rate is higher (1000pps), and the TX pulse width can be changed from the original (50us) to boost mode (100us), there is an improved detection range.

[lc516]

This is a nice project , especially for learning and education, but let me make some changes to the
circuit.

[ATTACH]54816[/ATTACH]

That's looks more concisely.
Is it have same sensitivity with original design?