AY Questions

ZXNet echo conference «zx.spectrum»

From Vladimir Yudin To All 24 September 1997


Hello All!

Here are some questions:
1. What is the signal shape of AY? (Sine or rectangle)
2. What is the frequency of the CLOCK signal (1.75 or 1.7734 or something else)
3. What will be the frequency of the tone (noise, envelope) if there is 0 in the register?
Or is zero the maximum value?
4. Is noise an n-random value supplied at a given frequency?
5. What is the signal level for each of 16 volume values in %?

That seems to be it! :)
Sincerely
┬ ┬┌┐┬┐ ┐┬┬
╨╜╨╙╜╨╙ ╨ ╨


From Roman Petrov To All 26 September 1997


Hello! Dear Vladimir!

At 21:15, Wednesday September 24 1997 there was such a thing that
Vladimir Yudin scribbled a letter All:

VY> Here are some questions:
VY> 1. What is the signal shape of AY? (Sine or rectangle)
Rectangle, although I once looked at the shape - it’s not similar, but when I synthesized it myself - it’s very similar.
VY> 2. What is the frequency of the CLOCK signal (1.75 or 1.7734 or something else)
1.77345 MHz (data from Z00LOOK)
VY> 3. What will be the frequency of the tone (noise, envelope) if there is 0 in the register?
VY> Or is zero the maximum value?
With frequency - silence, with envelope - absence of envelope, with noise -
maximum value (for example, I calculated the noise frequency using the following
formula: Freq=CLOCK/16/(Noise_freq+0.0001) - this is how I avoided dividing by 0)
VY> 4. Is noise an n-random value supplied at a given frequency?
Exactly so, that is, sampling the next number of a n-random sequence
(0 or 1) occurs at a certain frequency.
VY> 5. What is the signal level for each of the 16 volume values in %?
I don’t remember :(

With respect, Roman.


From Vladimir Yudin To All 27 September 1997

VY>> frequency?
RP> Exactly, that is, the selection of the next number of a n-random
RP> sequence (0 or 1) occurs with a certain frequency.
What does 0.1 mean? Are only MAX and MIN values ​​taken or intermediate
too?

Sincerely
┬ ┬┌┐┬┐ ┐┬┬
╨╜╨╙╜╨╙ ╨ ╨


From Danil Ermakoff To All 28 September 1997

RP> I don’t remember :(

I dug it up here from an old book, there’s a whole diagram. The level actually changes according to
logarithm (or whatever), I won’t draw everything, but something like this:

Uout VolReg
1v 15
.707 14
.500 13
.303 12
.250 11
.151 10
.125 09

further illegible, but in the same spirit...

RP> With respect, Roman.

C U L8ER, Danil.
[Green KillarZ Team][Bus CrasherZ Team][Legalize Team][Box Dancerz Team]


From Roman Petrov To All 30 September 1997

DE> from here I dug up from an old book, there’s a whole diagram. The level
DE> changes according to the logarithm (or whatever it is), I won’t draw everything, but
DE> something like this:

DE> Uout VolReg
DE> 1v 15
DE> .707 14
DE> .500 13
DE> .303 12
DE> .250 11
DE> .151 10
DE> .125 09

DE> further is illegible, but in the same spirit...
Further IMHO is not there at all - I have the same book :)
I haven’t understood this “same spirit” yet: is there some kind of dependence there?

With respect, Roman.


From Nicolaus Mezencef To All 7 October 1997

RP> Next, IMHO, it’s not there at all - I have the same book :)
RP> I haven’t understood this “same spirit” yet: is there some kind of
RP> dependence?

see above

Nicolaus.


From Vladimir Yudin To All 7 October 1997


Hi Danil!

08 Oct 97 19:01, Danil Ermakoff wrote to Roman Petrov:
DE> From the above series, no dependence is visible?
DE> I must admit, I remember lousy algebra:(

0.7^x (where x=15-loudness)
Yours sincerely
┬ ┬┌┐┬┐ ┐┬┬
╨╜╨╙╜╨╙ ╨ ╨


From Danil Ermakoff To All 8 October 1997


Hello Roman!

Tuesday September 30 1997 14:55, Roman Petrov wrote to Danil Ermakoff:

RP> Hello! Dear Danil!

RP> At 11:14, Sunday September 28 1997 there was such a thing that
RP> Danil Ermakoff wrote a letter to Roman Petrov:

skp...