Help for PI 4 Project

[Dixix]

I built the circuit PI4 (Page 169/190, "Inside the metal detector"). Unfortunately it does not work. from the speaker, only a steady tone. On page 190, the capacitor C3 is drawn in the layout. C3 but missing in the Parts List. I have used the 1 nF capacitor. I have to take it out again C3? Thanks for the help.

[Qiaozhi]

This one is really for Carl, but I can definitely say that you need to have C3 fitted.

You will have to supply more information than "it does not work. from the speaker, only a steady tone". Do you have access to an oscilloscope?

[Dixix]

Hi,
Yes, I have a small PC oscilloscope. Where can I measure. What voltage must be applied to the pins of the PIC (reference voltage?).
Thank you.

[Dixix]

Maybe I have not programmed the PIC correctly. I use the PICkit 2 programmer. I Wnn the HEX file import first comes the following warning:



If I then all the "Write" button is push but ok.



Maybe here is the error?
Regards, Dirk

[6666]

Dirk
I got the same error message as you
"some configuration words not in hex"
but it programmed OK.
The book talks about R6 may need some adjustment
but does not give much detail about it.

[Dixix]

I could replace R6 (22kohm) by a pot. But I want only times left everything like that. I have just rebuilt the circuit (with the NE5532), so it should work. This circuit is pretty small. Maybe Carl has another idea. Again and again I've checked everything. Nevertheless, I must have done something wrong. In the meantime, I'm going to build the circuit PI3. This circuit is a little bigger. Hopefully it works out better this time.
Dirk

[technos]

I do not know if you have seen this page, but there is an email address to use fwith erratta (which I suggest you use);
http://www.geotech1.com/forums/content.php?143-updates

I have not had the opportunity to get the book just yet, so it's difficult for me to follow along without a schematic.

[Carl-NC]

C3 should be included, however the circuit will work without it, just might be a little noisier.

I assume you've check the power and virtual ground voltages. Look at Q1/Q2 to make sure they are getting pulsed correctly. Also IC1's output for proper RX signal.

- Carl

[Dixix]

Thanks for the advice! I have the following (extensive) measurements were performed:

Q1: E-0V / B-0V /C--10,7V

Q2: Gate-10,7V / Drain-0V / Surce-10,7V

NE5532: Pin1-5,78V
Pin2-5,36V
Pin3-5,30V
Pin4-0V
Pin5-5,12V
Pin6-5,35V
Pin7-5,35V
Pin8-10,7V

PIC12F1840: Pin1-5,3V
Pin2-0,32V
Pin3-0V
Pin4-5,22V
Pin5-0,04V
Pin6-0,01V
Pin7-5,7V
Pin8-0V

Coil: -- 2,4 Ohm / 358µH

I use a 9V Accu-block with 10.7 V output voltage.

Thanks for the help!
regards
Dirk

[Dixix]

Has anybody an idea what I could try? Is it possible that the hex file was not properly loaded into the PIC?
I have also built the PI-2 project. It also does not work. The same error message when loading the hex file. Another project with PIC from this forum that I have built is running without problems! No error message when loading the hex file. I'm completely stumped. It is a pity that even the projects from the detector - book does not work. I would still like to learn.
Thanks for the help!
Dirk

[Qiaozhi]

Has anybody an idea what I could try? Is it possible that the hex file was not properly loaded into the PIC?
I have also built the PI-2 project. It also does not work. The same error message when loading the hex file. Another project with PIC from this forum that I have built is running without problems! No error message when loading the hex file. I'm completely stumped. It is a pity that even the projects from the detector - book does not work. I would still like to learn.
Thanks for the help!
Dirk

You said that you are getting an error message when loading the hex file. What is the error message?

[Carl-NC]

Is the PIC creating the proper TX pulse? If it is not, then it didn't get programmed correctly.

[Dixix]

Hex-file

Thanks for the quick response!

You said that you are getting an error message when loading the hex file. What is the error message?

While trying to write the .hex file into pic using pickit 2. before clicking on write" , a warning message appeared in the box:
"Warning some configuration words not in hex file
ensure default values above right are acceptable "

I must admit, I have more experience with the program AVR's.
Programming with PicKit is new territory for me...

Is the PIC creating the proper TX pulse? If it is not, then it didn't get programmed correctly.

No, the microprocessor does not pulse. I tried to test it with a 1-channel oscilloscope. (now I borrowed a 2-channel oscilloscope ordered).

[Qiaozhi]

Thanks for the quick response!


While trying to write the .hex file into pic using pickit 2. before clicking on write" , a warning message appeared in the box:
"Warning some configuration words not in hex file
ensure default values above right are acceptable "

I must admit, I have more experience with the program AVR's.
Programming with PicKit is new territory for me...

No, the microprocessor does not pulse. I tried to test it with a 1-channel oscilloscope. (now I borrowed a 2-channel oscilloscope ordered).

When programming a PIC from the ICSP socket, you need to turn on VDD. In the PICKit 2 menu, under PICKit 2 Menu, click in the "On" box.

[Carl-NC]

The Configuration bits look wrong, they should result in C9FC 3FFE. The bits should be set in the hex code, so it's possible the Pickit2 is overriding the settings. Poke around the menus and see if there is a selection for this.