gscartsw / gscartsw_lite / gcompsw switches support thread

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toxictigga
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by toxictigga »

I got the gscartsw in today. This is version 5.3. I tried plugging in the xbox, snes and nes SCART cables. I only hear audio and there is no video. Cables are all from retrogamingcables UK.

I tried just plugging in one device at a time and same issue. Plugging in directly to the TV works without any issues.

Do you know how I can go about diagnosing this issue? Is there a common troubleshooting guide somewhere?
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Kez
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by Kez »

What cable are you using to go from the gscartsw to the TV?
toxictigga
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by toxictigga »

Kez wrote:What cable are you using to go from the gscartsw to the TV?
I’m using a Sony SCART male to male cable, which works perfectly fine with Raspberry Pi Pi2SCART setup. Seems like I’m only getting 1.8V on pin 16. I’d need 5V to blank my RGB modded TV. Could that be the issue?

Edit- I read a post from superg where it is recommended to create a custom SCART male-to-male cable with a divider for pin 8 voltage. $300 CAD spent on the switch and now I have to make a custom cable. Fun!
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

toxictigga wrote: Edit- I read a post from superg where it is recommended to create a custom SCART male-to-male cable with a divider for pin 8 voltage. $300 CAD spent on the switch and now I have to make a custom cable. Fun!
No need to be toxic.
gscartsw forces 4:3 and RGB mode on pin 8 / 16 no matter what console provides, it's all overriden.
If it doesn't reach your TV cable is the problem, that's why you got asked about the cable.

EDIT:
SCART pin 8 specs are:
0–2 V → off
+5–8 V → on/16:9
+9.5–12 V → on/4:3
gscartsw forces 4:3 mode, I don't remember exactly but I think it's either 10V or 12V.

SCART pin 16 specs are:
0–0.4 V → composite
1–3 V → RGB
gscartsw provides 1.8V, it's in a middle of RGB 1-3V range.

If your TV doesn't switch to 4:3 or to RGB mode, it's your TV problem and the proper way would be to fix your not up to spec TV modification.
Making a modified cable with divider / charge pump is barely a solution, it's rather a quick hack.
toxictigga
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by toxictigga »

Sarcasm aside. Thanks for creating this switch. It is built really nice and I respect all the work that went into building this.

What I’m trying to understand is one simple thing. Consoles by default output 5V on pin 16. This seems to be the case with all the consoles I have tested. Why is retrogamingcables passing this 5V on pin 16? Have they all gone toxic?
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

toxictigga wrote:What I’m trying to understand is one simple thing. Consoles by default output 5V on pin 16. This seems to be the case with all the consoles I have tested. Why is retrogamingcables passing this 5V on pin 16? Have they all gone toxic?
You're forgetting one thing, there is usually a resistor there. You get 5V reading when you don't put any load but if you measure it connected to the TV circuit (upscaler etc.) you will see that it drops to the proper value. That's why 5V consoles have 180ohm resistor, 12V - 560ohm and so on.
toxictigga
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by toxictigga »

I think we are comparing apples and oranges here.

Leaving the load aside, just checking the voltage on pin 16, it is 5V coming out of consoles and 1.8V on the SCART output when plugged into gscartsw. This is the discrepancy we need to discuss.

If we add the load (CRT in this case) and if there is a resistor inside the TV that creates a divider then we need to measure the divided voltage in both scenarios. Not compare one with the load vs gscartsw without the load. If we add the load with gscartsw, then 1.8V will be divided further.

If there is a quick and easy way to route 5V to pin 16, please let me know. If not, I'm ok making a SCART cable. But, please do consider this customer feedback in future builds.
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

toxictigga wrote:I think we are comparing apples and oranges here.

Leaving the load aside, just checking the voltage on pin 16, it is 5V coming out of consoles and 1.8V on the SCART output when plugged into gscartsw. This is the discrepancy we need to discuss.

If we add the load (CRT in this case) and if there is a resistor inside the TV that creates a divider then we need to measure the divided voltage in both scenarios. Not compare one with the load vs gscartsw without the load. If we add the load with gscartsw, then 1.8V will be divided further.

If there is a quick and easy way to route 5V to pin 16, please let me know. If not, I'm ok making a SCART cable. But, please do consider this customer feedback in future builds.
I don't think you understand. There is no any discrepancy. gscartsw doesn't connect input SCART pin 8 and pin 16 at all. Regardless of the input number, console connected and cable used, input pin 8 and pin 16 is getting ignored. On gscartsw output SCART, pin 8 and pin 16 is functioning the way I described in my previous comment.
These pins are disconnected on input for a lot of good and proper reasons. First of all, there are cables which don't route those pins at all, second, it's always 4:3, even in WII case if it incorrectly sets 16:9 - the pic is still 4:3 so it fixes WII. Last thing, routing two traces per input to the output and creating a circuit around that is expensive (a lot of components) and as detection is composite based - it's not really needed.

I will just mention one final thing, you always get 1.8V on pin 16, if that doesn't work for you, modify your TV modification so it follows the standard and it will work for all cases, not just gscartsw. If you need more than 1.8V, replace the resistor on the recieving side or install charge pump, this is easy for a person who knows basic electronics.
toxictigga
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by toxictigga »

Your suggestion of changing the TV circuitry to take 1.8V is a sure fire way to fry the TV electronics, when you accidentally plug in the reputable retrogamingcable in the blindly modified TV. It is basic electronics. I don’t think you understand what I’m trying to say. I get your reasoning on why you did what you did. While this switch works for PVMs out of the box, this switch does not work for majority of the people with RGB modded TVs. Period. There needs to be a dip switch or some mechanism to control the voltage on pin 16 universally.

I really don’t care about pin 8. Irrelevant to our discussion. I’m also going to stop here, as we are not getting anywhere.
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

toxictigga wrote:Your suggestion of changing the TV circuitry to take 1.8V is a sure fire way to fry the TV electronics, when you accidentally plug in the reputable retrogamingcable in the blindly modified TV. It is basic electronics.
5V with 180 resistor completed by the TV circuit becomes the same ~1.8V under load :), it doesn't matter if it's direct 1.8V or 5V plus resistor given the TV circuit properly designed.
But Youtube/Reddit generation won't get it. Go learn something my friend and I assure you I won't move a finger to help you as you're rude and ungrateful so all your further complains and unhappiness can go directly to CastleMania Games.
Meanwhile I'm locking this thread because I am sick of people like you.
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system11
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by system11 »

Locking thread by request as OP no longer provides support for this product, feel free to start a community thread if it's useful.
System11's random blog, with things - and stuff!
http://blog.system11.org
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