Help for PI 4 Project

[bernte_one]

you can download all datas here from Forum
there is a storage for the Project of the itmd book
the gerber and eagle files and also the hex are available
you can Import the gerber to sprint layout if it is your favourite

i could upload my sprint lay files here but it would be the same of you load them direct from here

[bernte_one]

http://www.geotech1.com/forums/conte...57-source-code

[6666]

Hi Bernte_one thanks but how did you load the hex file into the pic ?

I have full version of sprint layout 5.00 but only demo of layout 6.00

[bernte_one]

1. load the gerber files from this Forum
2. open sprint layout 5 than main menue and Import - gerber select copper and silkscreen
3. for burning pic- best is to use pickit 3 with Software which belongs to pickit3 bundle http://www.microchip.com/Development...artNO=PG164130
4. make new Project, select correct pic type- all families - pic12f1840, select prebuild hex, and set the pickit to supply voltage 5v under Options /power
5. connect pic12f1840 to programmer (just 5pins) then click run in the Software and the hex is sent to the Controller if all is done you get a message

[bernte_one]

can i change the Audio tone in this lines:?

Timer1Delay(AudioDelay); // Delay for audio
PWM = 1;
Timer1Delay(AudioWidth); // Speaker pulse
PWM = 0;

is it possible to to set a lower threshold Sound?

[bernte_one]

i have wound another ferrite coil with 0,4 and 0,5mm magnet wire and L of around 300µH, can achieve 2,5-3c, for Gold Nugget of 10*5mm in air (0,39gramm) 1€ coin 8,5cm with clear Sound, tested core material 8mm and 16mm ferrite 50mm Long wound one layer of wire hole lenght

[bernte_one]

which is the best possibility to change the threshold sound from pi-4?
(i hope the answer is not - Change the code)

[raygdunn]

which is the best possibility to change the threshold sound from pi-4?
(i hope the answer is not - Change the code)

Hi Bernte

I feel that I should reply, as there have not been many people active with the PI-4 in recent times. Please take this as a non expert reply...☺ and I've yet to try fully understanding the PIC code.

If by threshold you were looking for more sensitivity, then I would try increasing the preamp gain by changing R8 feedback from the present value of 100K ohms towards 1M. Which I think I've seen in a few other designs. I think that D4 across it limits the voltage swing to the PIC ADC pin. There may of course be good reasons beyond more noise amplification for the current limit.

If you were looking to make the audio tone more mellow, I'd be looking at Dooley's TDX3 for inspiration to smooth the square waveform with more components.

Are either of those what you had in mind?

Ray

[bernte_one]

Thanks for your advice Ray.

some postings before i posted the command lines from code which i expect to to some changes on threshold Sound
i love a litte bit of threshold but not that noisy one from pi4

other think is to manipulate the sens of this detector

only think that is give is the trimpot in this design but it seems it is not a sens pot itself it is more for tune the different coils to work

i try experimeting with R8 also i think about the Diode function

i think i put this all into a pipe with a monoloop coil 18cm for underwater use
not sure this time i use clear acrylic housing and led indicator or Vibration Motor

will see

best regards

[raygdunn]

can i change the Audio tone in this lines:?

Timer1Delay(AudioDelay); // Delay for audio
PWM = 1;
Timer1Delay(AudioWidth); // Speaker pulse
PWM = 0;

is it possible to to set a lower threshold Sound?

Hi Bernte,

I've found your earlier post and had a quick look at the code.

About 7 lines from the end there is the following line:

if(dc.value < THRESH) dc.value = THRESH;

After the above line add the following line to set zero volume as the default and reduce the volume at all response levels. If the reduction is too much, then replace the value THRESH with a one. (THRESH currently gives a value of 2)

dc.value -= THRESH;

I hope that improves things...

if there is no space for the addition try adjusting the define of THRESH.

Ray

[bernte_one]

Hello Ray,

i have changed R8 to 1M but that seems not to increase the Performance.
Best way would be re-coding. Instead Speaker you can use bright White led (3,5V 20mA with resistor 82R).

[raygdunn]

Hello Ray,

i have changed R8 to 1M but that seems not to increase the Performance.
Best way would be re-coding. Instead Speaker you can use bright White led (3,5V 20mA with resistor 82R).

Hi Bernte,

Well it was worth a try to increase the voltage variation going into the micro-processor. 1M is I think a x10 gain one the preamp, so perhaps less is better.

I see you found an effective solution to the sound.. use a LED☺

Ray

[bernte_one]

my plans


i think you know what this is

[6666]

my plans
[ATTACH]36356[/ATTACH]

i think you know what this is

Nice !