GBS 8200/8220 CFW Project

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rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Ah, I see that sanni uses 2 devices in his design. And yeah, that will (should) not work.
The problem is that the DAC would have to source too much current to drive this load.

Instead of a $10 VGA splitter, why not go with a $17 GBS8220?
But that splitter should work. It has an external power supply input at least.

The GBS8200 doesn't carry 5V on the VGA 5V pin.
retromaniak
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Re: GBS 8200/8220 CFW Project

Post by retromaniak »

rama wrote:The GBS8200 doesn't carry 5V on the VGA 5V pin.
That's why I thought that a bridge could be made from the + 5V line to the 9 VGA pin. Then he would give voltage on VGA. I don't know electronics very well, but this shouldn't damage the system.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

You could do that. VGA pin 9 is isolated / not connected to anything on my test GBS pcb.

However, having 5V on the pin does not change the RGB termination situation.
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maxtherabbit
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Re: GBS 8200/8220 CFW Project

Post by maxtherabbit »

rama wrote:You could do that. VGA pin 9 is isolated / not connected to anything on my test GBS pcb.

However, having 5V on the pin does not change the RGB termination situation.
+1

not sure where he got the idea that +5 on pin 9 changes anything with respect to driving video :?
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

That's okay though. Could always be some misunderstanding :p

But yeah, only the GBS8220 has the additional amplifier that allows connecting 2 devices to it.
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

just uploaded the newest gbscontrol, and im getting a weird flicker that seems to happen every second, the screen will "jump"

Output looks like this:
post preset done (preset id: 3) for 60Hz

..*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*
.*.*.*

Sometimes it will stop, and then sometimes it will just start again randomly.

https://www.dropbox.com/s/0hgkwab25fhsw ... 4.mp4?dl=0
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Sub-coast / HSync coast failure.
Is this with CSync or is it Sync on Composite?
Can I see 3 lines of info mode for this as well?
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

rama wrote:Sub-coast / HSync coast failure.
Is this with CSync or is it Sync on Composite?
Can I see 3 lines of info mode for this as well?
info just looks like what I posted above, unless you mean something else?

Csync, yes.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Development > print infos
I need a few lines of that to see some basics stats about the signal.

But if it's CSync, this already shouldn't happen.

Edit:
In any case, there's some refinements in the latest update. Could you check whether that helped?
Iraito
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Re: GBS 8200/8220 CFW Project

Post by Iraito »

The OPL problem was related to that software.

Now i'm trying to update the GBS but i get this:
Sketch uses 482688 bytes (46%) of program storage space. Maximum is 1044464 bytes.
Global variables use 33304 bytes (40%) of dynamic memory, leaving 48616 bytes for local variables. Maximum is 81920 bytes.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

That's just a regular message. It should then upload the sketch.
Iraito
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Re: GBS 8200/8220 CFW Project

Post by Iraito »

Good to know, i asked because previously that message didn't appear in my log (maybe i never noticed it)
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

Code: Select all

h: 428 v: 523 PLL:16 A:4c4c4c S:02.18.20 H-   I:40 D:0584 m:0 ht:2345 vt: 261 hpw: 154 u: 14 s:13 W:-47
h: 428 v: 523 PLL:16 A:4c4c4c S:02.18.20 H-   I:40 D:0584 m:0 ht:2345 vt: 261 hpw: 154 u: 15 s:13 W:-47
h: 428 v: 523 PLL:16 A:4c4c4c S:02.18.20 H-   I:40 D:0594 m:0 ht:2345 vt: 261 hpw: 154 u: 15 s:13 W:-46
h: 428 v: 523 PLL:16 A:4c4c4c S:02.18.20 H-   I:40 D:0584 m:0 ht:2345 vt: 261 hpw: 154 u: 16 s:13 W:-46
h: 428 v: 524 PLL:16 A:4c4c4c S:02.18.20 H-   I:40 D:0584 m:0 ht:2345 vt: 261 hpw: 154 u: 16 s:13 W:-45
*h: 428 v: 520 PLL:15 A:4c4c4c S:02.18.20 H-   I:40 D:058c m:0 ht:2465 vt: 261 hpw: 154 u: 18 s:13 W:-45
h: 428 v: 523 PLL:14 A:4c4c4c S:02.18.20 H-   I:40 D:058c m:0 ht:2458 vt: 263 hpw: 156 u: 19 s:13 W:-45
h: 428 v: 523 PLL:13 A:4c4c4c S:02.18.20 H-   I:40 D:058c m:0 ht:2466 vt: 260 hpw: 161 u: 1a s:13 W:-44
h: 428 v: 523 PLL:11 A:4c4c4c S:02.18.20 H-   I:40 D:058c m:0 ht:2448 vt: 262 hpw: 162 u: 1b s:13 W:-45
h: 428 v: 523 PLL:10 A:4c4c4c S:02.18.20 H-   I:40 D:058c m:0 ht:2449 vt: 261 hpw: 161 u: 1c s:13 W:-45
h: 428 v: 523 PLL:09 A:4c4c4c S:02.18.20 H-   I:40 D:058c m:0 ht:2443 vt: 258 hpw: 160 u: 1d s:13 W:-45
h: 428 v: 523 PLL:08 A:4c4c4c S:02.18.20 H-   I:40 D:058c m:0 ht:2468 vt: 260 hpw: 162 u: 1e s:13 W:-45
h: 428 v: 523 PLL:07 A:4c4c4c S:8f.10.20 H-   I:40 D:0508 m:1 ht:2452 vt: 261 hpw: 161 u: 1f s:13 W:-45
This is on my 1-CHIP-01 SNES with RGB bypass installed (csync)

I get the same issue with my Sega Saturn too. (Only 2 consoles I've tried)
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Hmm, that doesn't make any sense at all.
Did you have sync issues in the past with these consoles?
Is this with the latest update?

The sync processor reports a stable NTSC format, but the mode detect unit claims an unknown video mode.
This continues until it suddenly does detect it.
I imagine this would be wholly unstable all the time.
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

It's like how I showed in the video. I never had any sync issues with the last couple of updates.

Ok, it's the sync stripper on my Gscart switch. I disabled it, and the issue is gone. Weird.

Edit: Ok the issue is still there, although it happens much less frequently when the sync stripper is disabled.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

It'd be great to see the waveform of that processed sync signal.
Something it does must be wildly different from what I expect.

Well, in any case, the GBS has issues with the embedded VSync somehow.

The best explanation to this is that the CSync signal is marginal to some parameter, possibly the SOG sync slicer level.
This may happen if the CSync that arrives at the TV5725 SOG input pin is weak (less than ~ 0.1Vpp).
Unfortunately we won't know without actually taking a scope to the pin.
Last edited by rama on Wed Dec 04, 2019 3:39 pm, edited 1 time in total.
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Syntax
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Re: GBS 8200/8220 CFW Project

Post by Syntax »

Syntax wrote:I should mention the GBS was doing a really funny thing with the picture but would clear up on reset, or id start with my PC engine then switch to the CPS2.

The image was smeared, very dull and rainbowy.( like a subcarrier going out of spec). Not sure what was going on there, bad clamp?
This got worse and wouldnt change. Tried a heap of things tonight like reflashing, different PSU ect.

Ended up reflowing every pin on every chip, gave it a scrub and its working sweet again.

Noticed my VGA connectors are going rusty...

Two switches were also corroding the board which is odd, must be dissimilar metals used. Ill be removing all buttons and placing the ESP there.

Oh well, who knows what it was but its running fine again now.

@AndehX
That looks like weak/bad sync to me. I get that on my brothers PCE with composite video sync. Buffered csync cleared it up for me.
remove all switches inbetween and test only directly connected.
GScart has a sync stripper AND an sync regenerator/reclocker
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

I did replace C33and C35 with 1nf capacitors a while back. I know that those capacitors don't need to be replaced anymore. Could that be causing the issue?
Syntax wrote:
Syntax wrote: That looks like weak/bad sync to me. I get that on my brothers PCE with composite video sync. Buffered csync cleared it up for me.
remove all switches inbetween and test only directly connected.
GScart has a sync stripper AND an sync regenerator/reclocker
That is true, although I have an early model gscart, so I don't think it has the sync regenerator. I disabled the sync stripper though and the issue mostly clears up, although it just "jump" every now and then still.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

The changed SOG coupling capacitors are okay.
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

All I can think is that my gscart must be doing something to the sync signal, even though the stripper is disabled... :/
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

It probably does. It's important what exactly though, to know why it fails now.

If you can, try and connect the consoles directly, see if that solves the issue or not.
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

Yeah it's definitely the gscart. Connecting them directly fixes the issue completely. I wonder what it is then... Maybe it's that vsync signal interfering with it?
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Since the problems started with my latest changes, I'll assume the device modifies VSync serration and/or equalization pulses.
I attempt to mask them (for lots of reasons), using conservative window widths.
Also, VSync has to have a minimum pulse length, before it's being considered valid.

All the values are chosen such that all my devices, in all their possible video modes, work correctly.
I support SNES 239 mode as well as PS3 1080p, and everything in-between.

So yeah.. would love to see the waveform for this.
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Syntax
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Re: GBS 8200/8220 CFW Project

Post by Syntax »

Smashed out the Panasonic 3DO 262P fine also.
Once again looked better than undialed OSSC settings.

Also all my consoles go through an Extron matrix switch which reclocks sync and boosts it to TTL.
There's a 470R resistor on my sync line and everything is still running fine on the latest firmware.

GScart must be doing something sketchy.
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AndehX
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Re: GBS 8200/8220 CFW Project

Post by AndehX »

I'm gonna try completely disabling the vsync signal
rememberizer
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Re: GBS 8200/8220 CFW Project

Post by rememberizer »

rama wrote:
rememberizer:
The problem sounds like the mode detect unit doesn't recognize what the RPI sends.
I'm working on doing a little more with "unknown signal" situations, so maybe a future update improves the situation :)
Thanks for the response. I tried to send 320x224 and other lower resolutions but it still didn't work. I'm looking forward to that update! :D
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

AndehX:
So just to clarify, whatever your SCART solution does, it is changing your console's sync signal into something that the GBS has trouble with.
This doesn't mean that the SCART solution is badly designed or malfunctioning, only that we've found a particular combination that is incompatible.

How much is shipping from the UK to Germany you think? :D

rememberizer:
Well, the update is already out.
This tells me that the video mode isn't "unknown", but that the sync isn't within parameters to be considered stable.
Could you share your RPI setup and the text file that sets the video mode?
I have a Pi2 and Pi3 here.
DarkAries
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Re: GBS 8200/8220 CFW Project

Post by DarkAries »

Super interested in this project. Waiting for my ESP8266 to come in to give it a whirl. I was wondering though if it is possible to use another device to actually have control via hardwired ethernet instead of wifi.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Well, the ESP8266 doesn't usually come with Ethernet.
If you were to use an Ethernet enabled module though, the web ui / webserver should just work with it.
DarkAries
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Re: GBS 8200/8220 CFW Project

Post by DarkAries »

Yeah that's what I was getting at, if it was possible to use a different module that had ethernet instead of wifi. I am not well versed in the arduino world.
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