TurboSoundFM
ZXNet echo conference «hardware.zx»
Hello, CHRV
I have completed all my research regarding the appearance of noise in the FM channel of
YM2203.
Noises appear as a result of a very short WR signal in Turbo
mode. Those. The board is not intended for use with
unfinished implementation of Turbo mode.
For normal operation, you need to set WAIT when accessing ports,
so that the cycle is extended by one clock cycle.
This concludes my research.
Progress report:
1) CS signal is now static, which increases sampling stability
chip;
2) More correct work with the A0 signal for sampling the chip mode;
3) Implemented an internal frequency doubler without using an external one
chains.
The board will no longer be modified. I consider the result obtained
satisfactory.
==========================
The board will be delivered to customers starting tomorrow.
Hello fyrex
fyr> "Implemented an internal frequency doubler without using an external one
fyr> chains."
fyr> What does this mean?
This means that previously, to double the operating frequency for the YM2203, it was used
external RC circuit coupled with a circuit in the matrix. And now doubling the frequency
done entirely inside the matrix.
Hello, CHRV
Despite my above messages, the board was still modified
(revision C):
- made it possible to block FM;
- the analogue path of the FM channel has been corrected;
- balance of SSG and FM has been done;
- the firmware has been fixed in order to optimize the timing of control signals;
- protective coating of the boards has been made.
And most importantly, it all finally went into series:
http://www.nedopc.com/TURBOSOUND/ts-fm.php
http://www.nedopc.com/catalog.php
Meanwhile, ALCO and Shiru Otaku are preparing editor(s).
And documentation for the programmer has been prepared:
http://www.nedopc.com/TURBOSOUND/tfm-prg.zip
Hello, CHRV
Super! I'm saving up a coin for the device for my next order.
Hello, CHRV
CHR> Despite my above messages, the fee is still
CHR> modified (revision C):
CHR> - made it possible to block FM;
Will Digital Sound work?
Immediately after turning on the computer, without any initialization?
And where is the link to the editor, sources, player, etc.?
Hello new art
I'd like to listen to it on mp3 somewhere.
Hello, CHRV
CHR> Despite my above messages, the fee is still
CHR> modified (revision C):
CHR> - made it possible to block FM;
CHR> - the analogue path of the FM channel has been corrected;
CHR> - balance between SSG and FM;
CHR> - the firmware has been fixed in order to optimize the temporary controls
CHR> signals;
CHR> - protective coating of the boards has been made.
CHR>
CHR> And most importantly, all this finally went into series:
CHR> http://www.nedopc.com/TURBOSOUND/ts-fm.php
CHR> http://www.nedopc.com/catalog.php
CHR>
CHR> Meanwhile, ALCO and Shiru Otaku are preparing editor(s).
CHR> And documentation for the programmer has been prepared:
CHR> http://www.nedopc.com/TURBOSOUND/tfm-prg.zip
I looked at the diagram and had a few questions:
1. What does the VCCA signal generate? (by the way, it’s generally called correctly - VCA ;)
)
2. It seemed to me that the VCCA signal only controls the volume of FM. I can't
understand why after 47k it is transferred to both opamps...
3. The output produces a general inversion of the signal?
Hello, CHRV
CHR> not just an amplified signal :v2_wink2;
A; the fact that the signal is supplied to the inverse inputs of the op-amp does not invert it by 180
degrees?
CHR> No, he is named VccA i.e. analog voltage supply, it does nothing
CHR> generates - a filter is simply made to cut off the noise of the power line.
Ahh... Vcc... Now I understand...
Then how do we understand: “- a balance has been made between SSG and FM;” ?
Hello, Evgeny Muchkin
Evg> I would like to listen to it somewhere in mp3.
I will definitely do this when I have free time.
Hello Mike
Mik> I looked at the diagram and had a few questions:
Mik>
Mik> 1. What does the VCCA signal generate? (by the way, it’s generally called correctly
Mik> - VCA ;) )
No, he is named VccA i.e. analog voltage supply, it does not generate anything
- a filter is simply made to cut off the noise of the power line.
Mik> 2. It seemed to me that the VCCA signal only controls the volume of FM. Not
Mik> I can understand why after 47k it is transferred to both op-amps...
No, it doesn’t regulate anything, it’s just that the opamps are made according to the amplifier circuit with
OOS, and between 47k and 27k is the reference voltage point.
Mik> 3. The output produces a general inversion of the signal ?
nope, just an amplified signal: v2_wink2:
Hello new art
new> Will Digital Sound work?
new> Immediately after turning on the computer, without any initialization?
new> And where is the link to the editor, sources, player, etc.?
The device is compatible with AU and TurboSound. By default (or by reset) it is installed
in TC mode (i.e. FM is blocked).
As the editor and player are prepared, everything will be posted.
Unfortunately there is no release version of the editor yet, there are several Mouzons
prepared by ALCO, Shiru Otaku and CJeff.
A small manual for programming FMT is here:
http://www.nedopc.com/TURBOSOUND/tfm-prg.zip
Hello Mike
Mik> And the fact that the signal is supplied to the inverse inputs of the op-amp does not invert it
Mik> 180 degrees ?
Inverts, there is an analog adder, with a midpoint of some volts (so
as the power supply of the op-amp is unipolar).
Hello Mike
Mik> Then how do we understand: “- balance of SSG and FM has been done;” ?
In the old scheme, FM was much quieter than SSG. Now the resistors are selected so that
there was balance. This will allow you to mix both sound reproduction methods normally.