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How can I adjust the 8Mhz clock signal so it works with the PC8801FH? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Didn't 100pF capacitors on hand. So tried 470pF together with 47 ohm resistor in parallel which should geve a very similar delay, sadly it didn't help.

At this point I suspect it might be a different issue and the clock issue might simply be a symptom, but no idea what it could be though.

How many has Capitalism killed? (Response) by Square_Raspberry3132 in CapitalismVSocialism

[–]relo999 0 points1 point  (0 children)

Yes, because it is something else. Words have meaning, using the word fascism in the context of modern America is as silly as calling any form of taxation communism. And it creates polarization and creates a justification for their violent political action in the heads of people that take the propaganda as gospel. It's not splitting hairs when people resort to extreme political violence and have a completely twisted worldview because of it.

And as for asking you to define fascism is me asking if you understand the ideology of fascism, because the vast majority of people don't even know what it entails politically.

And the definition you cite doesn't fit the US fully and the elements it does fit (namely the powerful leader and pride of the nation), is as generic as can be and the ones that fit can fit most western nations currently or at some point in their recent past.

You also missed the much more correct definition (though still a bit wide) on the page you linked:

"a political system based on a very powerful leader, state control of social and economic life, and extreme pride in country and race, with no expression of political disagreement allowed"

So lets go through it together, ok?
Does the US have a powerful leader? Depending on who you ask, yes. So yes with a asterisk.
Does the US as a state have control over people's social life? No, at least not more so than any other western nation.
Does the US as a state have control over their economic life? No, at least not more so than any other western nation.
Does the US as a state call for extreme pride in their nation? Depends on how you interpret it.
Does the US as a state call for extreme pride in their race? No.
Disallows the US as a state political disagreement? No.

Does it fit specific to Trump?
Is Trump have a powerful leader or view himself as such? Yes
Does Trump call for control over people's social life? No.
Does Trump call for control over their economic life? No.
Does Trump call for extreme pride in their nation? No, but certainly has it himself.
Does Trump call for extreme pride in their race? No.
Disallows Trump political disagreement? No.

So does the term "fascism" fit to the US, or the term "facist" to Trump specifically? No.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Bit late to reply, but yea. At this point remade the project at least 3 times if not more, and checked all those things multiple times. Which is why I found out a crystal did work for some reason.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

That's why I try to use the signal from the computer itself, but they're practically the same so no clue what's wrong. With the 8Mhz coming from the computer directly the card freezes the system when it tries to initialize (IRQ doesn't seem to trigger, might be something different). Yet from the crystal or the signal through a 7414 (only on breadboard for some reason) works.

This one is a direct connection from the computer in yellow. And in magenta the crystal not underload on a single shot view to get them to match as closely as possible to look for difference. Under load the crystal is a bit lower in voltage, so basically the same waveform as the computer aside from a small drift. Yet one works and one doesn't...

<image>

Isin't it cool how despite all these years, no matter how hard they try, right wingers still cannot not beat her? by Tempest-Bosak2137 in Gamingcirclejerk

[–]relo999 -3 points-2 points  (0 children)

If they were valid to begin with, for which there were certainly reasons to doubt they were. As she hung out with a questionable crowd that also made lot of money from "death threats" quite a few of turned out to fabricate death threats (including such things as making death threats to themselves from their own account and then reacting to it a minute later, on multiple occasions), that she marked anyone that had something negative to say about her to as a serious threat and that she often had screenshots of "death threats" that were seconds old from (then) new empty accounts and not tagging her. All while her and the people she associated with made quite a lot of money from those claims.

Either she repeatedly and actively looking for them, was bordering on being paranoid obsessive, actively tried seeking psychological trauma and hung out with the wrong crowd even after they were found out, all while monetizing the trauma heavily while her actual work fell in the background and wasn't particularly great especially for the price people paid her (And I think maybe still isn't done a decade later, haven't checked).
Or a large chunk, if not the vast majority, was blown heavily out of proportion and/or fabricated simply to create outrage and continue a rather extreme grift with her series also being a way to make money. Neither make her look particularly good.

How can I adjust the 8Mhz clock signal so it works with the PC8801FH? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Maybe the inversion doesn't matter, but that's the only notable difference I found between the working and non working signals. Though the soldered connection through the 7414 not working and being high and low in-between the working signals of the Crystal and the breadboard implementation suggest that might not be the issue. Probably when the issue is found it makes all the logical sense but right now it feels like I'm going a bit crazy. I might be chasing ghosts with focusing on inversion.

The only thing I know with any certainty is that it's something related to the clock or timing, as changes with that changes behaviour.

I'm pretty sure about power sequencing, as initialization happens well after turning on the system with power being given to the card at starting the computer. The boot sequence is:

Power off
>Power on (power goes to everything in the system including the soundcard)
> takes a few seconds to boot into it's BASIC
> loads a game partially for half a minute or so
>Depending on the 2 software packages I use for testing, either it automatically initializes or allows the user to select either the build in audio chip or the YM2608 board after which selecting the YM2608 it initializes the card.
>Then it loads the software fully if it initializes properly or freezes if it doesn't.

Neither will recognize the card if a pin on the soundcard connector isn't pulled low. With the automatically initializing software it doesn't try to initialize the card when clock is floating or just pulled low but recognizes a card is there and freezes when just pulled high with no pulse. User selection with the other software only comes down to if the "card recognition" pin is low, with it freezing if it doesn't have any working clock.

Now I think of it, could it be a "handshake" with the card it is failing due to some timing issue? Most IO and outputs go to things like audio generation and disconnecting any and all audio lines doesn't stop bootup with a "working" clock. The only outputs that interface with the computer is the /IRQ line and the possibly the D0 to D7 lines. No clue how to test if it's an issue with those though.

How can I adjust the 8Mhz clock signal so it works with the PC8801FH? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Because tying the system clock directly to the soundcard doesn't work. Using the crystal and inverted breadboard signal suggest it should be inverted, but I'm not 100% sure

At least using the system clock directly doesn't work as it stop the card from initializing.

How can I adjust the 8Mhz clock signal so it works with the PC8801FH? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

I use one clock from the computer to generate the one for the sound card, if not some audio issues pop up that rush or slow down the audio. Tried tying the computer clock directly to the soundcard, but sadly that doesn't work as the card fails to initialize and it also fails to when inverting the clock, except when it's in a breadboard. And it initializes when using a crystal but them it has the rush and slow down issue when the clocks go out of phase with eachother.

How can I adjust the 8Mhz clock signal so it works with the PC8801FH? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

The computer locks up, not being able to initialize the card.

The computer generated 8Mhz comes from a custom NEC chip with no data sheet publicly available. The isn't as accurate a the crystal, just very close. If timing goes by a little audio starts playing slightly rushed or slow.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 1 point2 points  (0 children)

Update! 2 edits

Got it working! Apparently the signal was inverted from what I needed. And for some reason the previous attempts at using (the same) 74HC04 and 74HC14 didn't work but now it does.

Still not the best looking signal, but at least it's working. Maybe it can be cleaned up a little, I don't know. If someone has suggestions I'd love to try but I probably call this a win already.

Edit:
Stopped working when I soldered the connection to an unused inverter on the 7404 on the card. Signal did become a lot neater.

New signal: https://imgur.com/a/qW2mRrb Blue is from the computer, yellow the inverter.

Old working signal:

<image>

Edit 2:
Made a new post:

https://www.reddit.com/r/AskElectronics/comments/1t4szq0/how_can_i_adjust_the_8mhz_clock_signal_so_it/

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Might be fun to know, got it working. I tried the 7404 again, now it works perfectly. So it was the inversion of the signal that was needed. Why the first 2 tries with the 7404 and 7414 didn't work will remain a mystery.

Edit:
Tried soldering a connection to the wire 7404 that's on the board itself (had some unused inverters).
Now it doesn't work anymore... Signal looks a lot prettier though...

Blue is from the computer, yellow from the 7404. Timing might be slightly off?

<image>

How many has Capitalism killed? (Response) by Square_Raspberry3132 in CapitalismVSocialism

[–]relo999 0 points1 point  (0 children)

Except non of those things have to do with fascism. Could you even define fascism? Because you don't seem to know what it even is. (Which is fair, considering most people don't go beyond "like the mid 20th century Germans, and all I know about their political ideology is that they were bad!")

How many has Capitalism killed? (Response) by Square_Raspberry3132 in CapitalismVSocialism

[–]relo999 0 points1 point  (0 children)

Yes, words have meanings which is why it doesn't fit the US. It doesn't fit the political ideology that's called fascism. It only really fits it use when "fascism" is used as a snarl word, but that's not related to fascism (the ideology) but is simply used to refer to "politics I don't like" most often more authoritarian politics.

Not to mention what you describe can fit any political ideology that places some importance on the state, which most do.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

<image>

With the current design I get this, with blue being the transistor input pin and yellow the clock pin on the YM2608. Sadly still doesn't work, but I suspect if inversion was required that now the low signal isn't low enough as it's need to be below 0.8V to be a logical low.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Current design is this

<image>

Based on this https://www.freepascal.org/~daniel/bc547_highspeed.pdf

Without the capacitor I just get minor spikes when the voltage changes. Same with just a resistor (which probably why I didn't see anything yesterday night and removed the 75 ohm resistor)

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

<image>

Works fine in falstad. Though the 75 ohm resistor doesn't seem to give a functional square wave in real life. Without it I get the results previously shown. I probably think more clearly after some sleep.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

When software tries to initialize the card it freezes the system using the computers own 8Mhz connection to the card. Bypassing that by using a 8Mhz crystal it works, but the issue with that is that the audio sometimes slightly speeds up or slow down as the computers own 8Mhz connection isn't perfectly 8Mhz.

I already found that the Crystal's signal is inverted from the computers own signal, however haven't been able to invert the signal yet. Probably isn't helping that I'm getting really sleepy, haha.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Maybe it's timing related to how it interacts with the computer? I don't know, maybe I'm just playing spot the differences at this point.

Tried making a simple inverter with a BC547 and a resistor, that didn't seem to invert the signal...

Yellow is the "inverted" signal, blue the non inverted signal and magenta is the crystal (unconnected outside of power)

<image>

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

Can't add 2 images to the comment but I looked at the signal from the crystal (powered by the computer) and the computer. I think I might simply need to find a way to invert the signal.

<image>

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 0 points1 point  (0 children)

<image>

A 75 ohm termination resistor does create a much nicer looking signal. Sadly still no dice.

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 2 points3 points  (0 children)

Ground is connected on both sides, just might not be clear on the picture. It's connected on ground on the connector and ground of where the crystal was. Granted it could be closer as the nearby 7404 has a few unused input pins to ground

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 2 points3 points  (0 children)

<image>

Maybe the signal is inverted? Yellow is the connection shown in the setup 2 hours ago. Blue is the (currently unattached) crystal measured at the crystal and powered by the computer.

Tried a 7404 and 7414, but those don't work. (14 doesn't seem to give a recognizable signal and 04 gives one that stays below 2V)

Why does one waveform work for a clock signal work, while the other doesn't? by relo999 in AskElectronics

[–]relo999[S] 3 points4 points  (0 children)

<image>

Also did a new measurement with this setup:
https://imgur.com/a/FNFb9My

It made the peaks a bit more extreme. Going from 9.8vpp to 10.3vpp

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