circuit problem

[Electrojosh86]

First off this circuit seems to be a little hard to read as, to me, it is poorly drawn. My first question here being on the PIC16F628a, Cause the way the lines are drawn I was wondering if pin 1 and pin 11 are really together or was it a mistake. Also, on the control buttons R1 seems to be have the line drawn all the way up to the top volume ctrl button and I was wondering if perhaps that should also be together or not. And to my biggest question being on the TDA7056. It seems that pin 5 is connected to R8 and R9 and also to the resistors on the 4066 but on the datasheet I see that pin 5 is NC. What is really going on here? Is this even a viable circuit to build? And is there a better circuit out there that I can use with the TEA5767?.. Thanks a bunch for helping an amateur out!

https://pdf1.alldatasheet.com/datasheet-pdf/view/19422/PHILIPS/TDA7056.html
https://320volt.com/en/tea5767-pic16f628-dijital-pll-kontrollu-fm-radyo-alici-sistemi/

 

[kam1787]

What is your goal? I guess you have some TEA5767 on hand.

 

[wp100]

Hi,

Its often so easy to make a mistake on a schematic diagram.
If you look at the PCB you will see that most of your questions are answered.
Its much more likely the pcb is correct.

As for Pin5 being connected to r8/9 etc, not sure why, but being as pin5 is said to be nc cannot see that it matters.

Like any web based project you have to ensure the code complies ok as well; though there is the .hex file in the zip folder.

Seems there are lots of similar web based projects so double check things against them.

Perhaps search the web to see if there are other comments about this circuit and if it works ok or even contact the guy and let him know about the errors /questions you have spotted, he might be happy to help correct/clarify things; (I would if it was my project )

 

[Electrojosh86]

Yes I do have some TEA5767 on hand and just wanted to use them. I did ask the person that submitted this project about the diagram and the mistakes made and he ensured me that there are no mistakes made so I figured I would just not use this project. I came across another TEA5767 project and I have made the microcontroller part and that part works well enough. Plus, that person has a good diagram and explains the circuit clearly and better.

 

[kam1787]

perhaps you could share that circuit

 

[Electrojosh86]

Sorry, I have been busy so I havent had time to share the circuit.

https://www.edaboard.com/threads/289529/#post1266888

I had the Microcontroller circuit working at one time and now it does not work at all. I have rebuilt, reprogrammed, and used a different PIC16F877a. When I go to program it on my cheap programmer it says "all fuses set to default".. not sure what that means. I know that the crystal is not in the schematic and I did use one the first time I built the thing and I do believe that it was a 20Mhz but now I cannot remember if that was the right frequency.

Here is what my cheap programmer says the fuses are at default.

WDT: Enabled
BODEN: Enabled
CPD: Disabled
Debug: Disabled
Code Protect: Disabled
PWRTE: Disabled
LVP: Enabled
WRT: Enabled
Oscillator: RC

- - - Updated - - -

Also, I do have some TEA5767's and I'd like to use them.

- - - Updated - - -

Nevermind, it seems that I had the wrong capacitors on the crystal and then changed the oscillator from RC to XT