240p via HDMI on Raspberry Pi to RGBS, no need for RGB hats!

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kitty666cats
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by kitty666cats »

I've recently dug out my 3B+ yet again, definitely psyched on the lo-tech VGA hat. I can confirm that any image/settings tailored towards the RetroTink Ultimate will work on this thing as well. Looks quite nice, definitely comparable quality to HDMI -> VGA solutions (except no 480i, but I only use my Pi for pre-PS1/Saturn era... so with the exception of Sonic 2 two-player and sparse few other games, it does not matter haha)
nowI'm_the_OldGeezer
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by nowI'm_the_OldGeezer »

I found that just changing

hdmi_group=1
hdmi_mode=21

gives me the best image but I am in a PAL region so that might be why as these two changes tell the Raspberry Pi to send a 576i signal https://www.raspberrypi.com/documentati ... #hdmi_mode
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gmipf
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by gmipf »

Fudoh wrote:after using various converters to get an analogue 240p signal from my Pi, I wanted to share my findings - possible to make the choice easier for anybody who wants to try this.

- Startech HDMI to VGA (actually VGA or component)
https://www.startech.com/en-de/audio-vi ... s/hdmi2vga
Works like a charm both in RGB and component. Works well with full range RGB HDMI output (which is my prefered setting). It's a powered DA converter, so one more PSU. High official price ($250?), but I got it cheap ($35) from ebay.
Maybe a little offtopic but I have got that Startech HDMI2VGA today. Paid only 35€ but he send me the totally wrong PSU (9V). I have found a fitting 5V 2.5A PSU of an old D-Link WLAN Router but according to the manual the device requires 2.6A. Should I buy a new one or is that 100mA difference not important?

It is also missing the DB15 to RCA adapter for Component, do anyone know the pinout for that cable?

I want to use it with an OSSC on a Sony G420 CRT monitor which I also got last week for 150€. A little expensive I think and it has geometry issues at the top.

Also tested the converter with a Leo Bodnar on a Benq RL2455. It doesn't seem to add any lag. But the weird thing is that the lag was lower than directly connected via HDMI. Direct over HDMI 0.8ms - 1ms vs HDMI2VGA as low as 0.3ms - 0.4ms. Is the internal circuitry of the LCD monitor slower over HDMI? I will test with Leo Bodnar on the Sony G420 tomorrow.
fernan1234
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by fernan1234 »

gmipf wrote:Maybe a little offtopic but I have got that Startech HDMI2VGA today. Paid only 35€ but he send me the totally wrong PSU (9V). I have found a fitting 5V 2.5A PSU of an old D-Link WLAN Router but according to the manual the device requires 2.6A. Should I buy a new one or is that 100mA difference not important?
Have you tried just plugging it to a USB hub or adapter? I have the same converter and I just use a DC to USB cable going into any USB power source. Saves on a wallwart and works perfectly.
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gmipf
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by gmipf »

I don't have any USB adapters delivering more than 2A. With how much Ampere do you drive your converter?
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vol.2
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by vol.2 »

gmipf wrote:Should I buy a new one or is that 100mA difference not important?
most likely will make no difference. i would just try it before spending money on anything.

It is also missing the DB15 to RCA adapter for Component, do anyone know the pinout for that cable?
I would imagine it's just a normal VGA pinout (DE15, DB15 is a very large size for a 15 pin connector and very rarely used). https://pinoutguide.com/Video/VGA15_pinout.shtml
fernan1234
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by fernan1234 »

gmipf wrote:I don't have any USB adapters delivering more than 2A. With how much Ampere do you drive your converter?
I don't think you need more than 2A, so any USB power source like your computer, etc. should work fine. I've only used it with 1080p and below with no issues. Maybe more amps would be needed if you go higher than that. Anyway, give it a try, won't hurt anything.
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