Hi there,
I am trying to write a software emulator for some circuits that were used in the 80's to generate sounds and effects in arcade machine. You can check:
http://www.ascotti.org/programming/side/soundboard.htm
to see for example the Space Invaders soundboard.
I wonder if some of you can help with this piece of circuit:
V1+  R1  C1  R2  C2  R3  V2+
(all capacitors also connected to ground). I need to determine the voltage across capacitor C2.
What I'm doing now:
 I charge C1 via V1 and R1;
 I charge C1 via R2 and C2 (doesn't seem to matter much);
 I charge C2 via C1 and R2;
 I also charge C2 via V2 and R3.
The above doesn't seem to be correct, but with my limited knowledge I can't do better (I have read the relevant chapters of the great "All About Circuits" guide and worked out the examples up to the "Complex RC circuits" with Thevenin's theorem, but I don't know how to apply that to my case).
If possible, I would like a formula that gives me the voltage across capacitor C2.
P.S. I have attached a picture with the whole circuit (it's the "fire" effect from Galaxian by the way), the part I refer to is in the lower right corner.
I am trying to write a software emulator for some circuits that were used in the 80's to generate sounds and effects in arcade machine. You can check:
http://www.ascotti.org/programming/side/soundboard.htm
to see for example the Space Invaders soundboard.
I wonder if some of you can help with this piece of circuit:
V1+  R1  C1  R2  C2  R3  V2+
(all capacitors also connected to ground). I need to determine the voltage across capacitor C2.
What I'm doing now:
 I charge C1 via V1 and R1;
 I charge C1 via R2 and C2 (doesn't seem to matter much);
 I charge C2 via C1 and R2;
 I also charge C2 via V2 and R3.
The above doesn't seem to be correct, but with my limited knowledge I can't do better (I have read the relevant chapters of the great "All About Circuits" guide and worked out the examples up to the "Complex RC circuits" with Thevenin's theorem, but I don't know how to apply that to my case).
If possible, I would like a formula that gives me the voltage across capacitor C2.
P.S. I have attached a picture with the whole circuit (it's the "fire" effect from Galaxian by the way), the part I refer to is in the lower right corner.
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