Audi Concert volume

[rimodar]

It has been some talk about the problem mentioned above,but i haven't seen any suggestion about writing virgin eprom info into the integrated MCU mc68hc705b32.Is it possible to write only eprom from the working mcu whose eprom is nearly new and unfilled with info about volume movement that this solution could work without heating mcu with heat gun,light bulb,or replacing it with a new one.Has anyone tried this and if it has is it possible to work for more than a year?Of course only in situations where the eprom is only full but functional....Does anyone has this kind of dump , i'm willing to try because i have one in hand with a mentioned problem...thanks for all the help in advance...

[bogege]

You may try this solution: .................

[ahmetusta61]

You may try this solution: .................


I have tried not worked

[damian475]

Look for this.

https://www.programatory.com/index.php?p1106,nowosc-modul-naprawczy-regulacji-glosnosci-audi-concert-oraz-chorus

[mikemike]

Hi! This works! I've tried it several times!

[rimodar]

I have read somewhere that this solution with PIC fixes the volume but other controls are useless,like treble,bass....is this true or not???For the chip board as an interface i'm familiar but the transport and the circuit board with expenses exceed the value of the radio....

[mikemike]

Hi!Treble,bass,fader,balance works!

[rimodar]

For mikemike-i have made this interface and tried it.The sound is lower
but none of the controls work.Before this sound was maximum,when tried
to lower controls react,but when the knob is stopped,the volume goes to
the maximum.With the interface installed the sound is 50% lower,stable,
without any control.In the schematics above,a few questions comes to
mind:first,in the picture in the rar file resonator is 8.00 Mhz,but in
the text file it is 8,664 Mhz,on the radio board is 4,332 Mhz???Which is
it??Second,positions of the 6 and 7 pin on the knob,in the text file
knob is drawn looking from the front of the knob or from the back of the
plate??And the last question,for all who knows ,which maybe my
mistake,when programming with Willem 3,5 pcb,i just loaded hex pic and
programmed the PIC without any settings.Is it necessary to make some
additional like oscillator adjustments while programming,to exclude the
mistake i have made maybe?

[mikemike]

Yes, sometimes the sound is only 50%, then try turn the radio off and turn it on.
For me all functions work well.
I tried with 7,2M,8M,8,664M resonators and works.
I writed(pic16f84a 20/P) with old willem pcb3.
I programmed the PIC without any settings.
6,7 pin from the front side volume knob.
(Sorry,i very little speak englis...)

[rimodar]

From your answer,i can tell you my doing so far:the board is done without mistake,programmed with the same programmer and the same settings,same connection,replaced 6 and 7 pins and vice versa,same PIC,rezonators 8 and 8,664Mhz,to resume everything is like you did,even tried to on/off the device,change HC to XT ,turned watch dog on willem and reprogrammed it(i gained with this some control but with the knob movement one step at the time - one high,two high,one lower etc and no maximum volume).No sound control in the way it should be....any suggestion to try something else or even a different program for the PIC....since i came this far....thanks anyway...

[rimodar]

For mikemike :project was left aside for a while,and i forgot to mention the difference between my project and mikemike`s.Everything is the same but one thing is not.I took 5V from LM7805 for the circuit, he took the power from the diode from the back of the mainboard.I tried to change something to look exactly like the project above,thinking that maybe the cable length was the problem,or the interference from LM,and connected the power as you did without checking the voltage.The voltage on the diode in the picture was 12V instead of 5V,and i ended up with a burnt PIC!!!!Can you explain how come that your project works with such a high voltage as supply for the circuit???I didn't see anything that lowered the voltage as an addition to the schematic?

[alexandr1966]

Work perfectly! I tried it with crystal oscillator 8 Mhz on AUDI CONCERT TT! Thank You Mikemike!