MiSTer FPGA Forum

Doozer wrote: ↑Tue Apr 05, 2022 7:16 pm If you are looking for the FW to pilot an iPad3/iPad4 screen with either an RTD2556T or RTD2550 you can try the following dumps below.

ipad_rtd2556T.bin

ipad_rtd2550.bin

Hi.
Do you know if this dumped rtd2550 firmware supports 640x480 vie VGA?
My board have a rtd2550 and it does not support this resolution.

sonik wrote: ↑Tue Apr 05, 2022 11:19 pm Do you know if this dumped rtd2550 firmware supports 640x480 vie VGA?

Unfortunately I cannot directly answer your question, I need to first test the resolution your are targeting. I assume your reference to VGA is about the resolution and not the connector. I only have a dual HDMI board fitted with RTD 2550. But this should not matter for a resolution test.

The resolution alone is not enough, what is the refresh rate to be associated to the 640x480 resolution? Based on the VGA specs it starts at 60Hz but can be higher. It might be possible that a new modeline with a different refresh rate would work.

Doozer wrote: ↑Wed Apr 06, 2022 7:50 pm Unfortunately I cannot directly answer your question, I need to first test the resolution your are targeting. I assume your reference to VGA is about the resolution and not the connector. I only have a dual HDMI board fitted with RTD 2550. But this should not matter for a resolution test.

The resolution alone is not enough, what is the refresh rate to be associated to the 640x480 resolution? Based on the VGA specs it starts at 60Hz but can be higher. It might be possible that a new modeline with a different refresh rate would work.

My board is VGA/HDMI.
I asked about vga but indeed my board does not support the resolution in any of the inputs.
Please if you can test 640x480@60 on mister or a pc.
I want to use the screen with my Dreamcast (it does VGA 640x480@60).

The stock firmware (RTD 2550 fw I provided) does not support 640x480 60Hz. But if you use this screen, why do you want to limit the resolution?

You can use one those two modes to have a real benefit with the iPad retina screen.

2048x1350 2048x1536

Native resolution (video_mode=13) does not work well with my screen. It blanks out in some MiSTer cores, specially jogego ones. On other cores it works perfectly.

640x480 is not for MiSTer. I want to connect a Dreamcast via VGA (480p) to it.
The board my friend have does work. Mine does not work at all at this mode.

sonik wrote: ↑Fri Apr 08, 2022 12:18 pm 640x480 is not for MiSTer. I want to connect a Dreamcast via VGA (480p) to it.
The board my friend have does work. Mine does not work at all at this mode.

Now I understand better. Unfortunately, it is better to stick to the Dreamcast hardware when it comes to test compatibility. Especially, to ensure the modeline settings are coming from true hardware specs. On this side, I cannot test further, I do not own DC hardware.

On the other side, if your friend have an identical board but different firmware. It is very likely that dumping his fw to flash it on your board will give you the same results. I personally would go that way.

Dont seems to be the same board/controller. His board does not even have the "firmware info screen" :/

If anyone is interested in purchasing this display from AliExpress, I DON'T RECOMMEND PURCHASING FROM THIS SELLER: Yqwsyxl LCD parts Store (https://www.aliexpress.com/store/910350379)

Unfortunately the package was stolen during shipping transit.

I noticed it because of the tracking record. I advised the seller about it, I purchased another unit and and I opened a dispute requesting the refund of my first purchase.

Seller denied the refund, told me to request compensation from the postal service company - although I explained many times that I had already tried it and they only compensate the sender, not the addressee - denied to ship my new purchase, offended me and my country.

After I registered a negative review, seller complained about it and kept insulting me and my country.

Unforeseen things can happen, but if you want to avoid problems due to the seller's attitude, stay away.

Doozer wrote: ↑Tue Apr 05, 2022 7:24 pm The tool from https://github.com/floppes/RTD266xFlash is producing good dumps with a RPI. The details about how to set it up is available in the readme.

Nevertheless, you will be able to flash a new binary without enabling the write operations. I think you already know this by reading you.

Unfortunately, it seems like nothing I do brings the display to life with any firmware but your 2550 dump - using a Raspberry Pi seemed slightly more successful, but the result is the same. It's completely non-functional with anything else. The closest I got was modifying the EDID in the 2550 dump and successfully flashing that, but that caused more problems than it solved - it proved the data is getting on there successfully, at least, and that it's possible to modify it.

The only real clues I have are a) that invariably, any flash but the 2550 dump results in a blank EDID according to i2c dumps, and b) that sometimes the firmware I flash reads out slightly differently to how I initially flashed it. But the last time was only by a few bytes.

What could be the difference between our boards, that flashing yours with alternate firmwares works and mine doesn't? What is the USB tool doing to make the code work that the available software methods are not? Is there some way to force it to work using i2c commands?

I might suggest you try using the RTD26xxPy tool to flash firmwares yourself, and see what happens and what the difference is. I'm not really in a position to spend $40 on a programmer tool that only might work, but I'm getting awfully tempted to.

sonik wrote: ↑Fri Apr 08, 2022 12:18 pm Native resolution (video_mode=13) does not work well with my screen. It blanks out in some MiSTer cores, specially jogego ones. On other cores it works perfectly.

640x480 is not for MiSTer. I want to connect a Dreamcast via VGA (480p) to it.
The board my friend have does work. Mine does not work at all at this mode.

Are you setting dvi_mode=1 and do you have overdrive turned all the way up in the display settings?

Queen Fiona wrote: ↑Sat Apr 09, 2022 10:28 pm [I might suggest you try using the RTD26xxPy tool to flash firmwares yourself, and see what happens and what the difference is. I'm not really in a position to spend $40 on a programmer tool that only might work, but I'm getting awfully tempted to.

I do own the programmer tool too. I can confirm that the dump from RPI and RTD tool are identical. There is something wrong if you read different values after the flash process.

Wrt to your friend's board, my understanding was that you both have the VGA + HDMI version. There are so many different boards that a visual inspection of both might be necessary to identify the components and see what could be done.

flynnsbit wrote: ↑Sat Apr 09, 2022 11:48 pm
Are you setting dvi_mode=1 and do you have overdrive turned all the way up in the display settings?

Dvi disabled. Where is this overdrive setting?

sonik wrote: ↑Sun Apr 10, 2022 10:21 pm

flynnsbit wrote: ↑Sat Apr 09, 2022 11:48 pm
Are you setting dvi_mode=1 and do you have overdrive turned all the way up in the display settings?

Dvi disabled. Where is this overdrive setting?

enable DVI, the the actual display settings OSD of the LCD there will be an overdrive, turn that all the way up. With both DVI on and overdrive re-test those cores you were having trouble with.

flynnsbit wrote: ↑Sun Apr 10, 2022 11:43 pm enable DVI, the the actual display settings OSD of the LCD there will be an overdrive, turn that all the way up. With both DVI on and overdrive re-test those cores you were having trouble with.

DVI enabled (tested as it does not output any sound) and I can't find this option on the screen's menu.

Doozer wrote: ↑Sun Apr 10, 2022 8:47 am

Queen Fiona wrote: ↑Sat Apr 09, 2022 10:28 pm [I might suggest you try using the RTD26xxPy tool to flash firmwares yourself, and see what happens and what the difference is. I'm not really in a position to spend $40 on a programmer tool that only might work, but I'm getting awfully tempted to.

I do own the programmer tool too. I can confirm that the dump from RPI and RTD tool are identical. There is something wrong if you read different values after the flash process.

Wrt to your friend's board, my understanding was that you both have the VGA + HDMI version. There are so many different boards that a visual inspection of both might be necessary to identify the components and see what could be done.

I have a dual mini HDMI board, with an RTD2550 chipset. An identical board was posted earlier, so I'll just use that picture:



Note that the flash chip covered in this picture was not covered on my board, and is labelled as a PUYA P25D80H; I couldn't find your ZBIT chip, but they may well be clones of one another. The datasheet is here.

I think its a total crapshoot as to if a monitor you get doesn't have sync issues or not. I posted a few months ago about sync issues with my LaserBear one. Greg replaced it, but I still have sync problems, even with the updated firmware. It's a bummer.

Tried the DVI & Overdrive thing but that didn't seem to help. Video Mode 13 is unusable basically which sucks. I get better results with:

video_mode=2048,48,32,80,1350,3,10,19,183087


But still some errors.

flynnsbit wrote: ↑Sun Apr 10, 2022 11:43 pm enable DVI, the the actual display settings OSD of the LCD there will be an overdrive, turn that all the way up. With both DVI on and overdrive re-test those cores you were having trouble with.

Hi. Sorry to bump again. I can't find the override option even when using dvi mode? Should I update the firmware to the one posted here?

sonik wrote: ↑Fri Apr 15, 2022 3:30 pm

flynnsbit wrote: ↑Sun Apr 10, 2022 11:43 pm enable DVI, the the actual display settings OSD of the LCD there will be an overdrive, turn that all the way up. With both DVI on and overdrive re-test those cores you were having trouble with.

Hi. Sorry to bump again. I can't find the override option even when using dvi mode? Should I update the firmware to the one posted here?

I dont have the new firmware so not sure if that changes things. Overdrive is in the actual display's menu itself. Menu--Advanced -- Over Drive -- On and OD Gain 100, And yes, DVI turns off audio but will give it a bit extra bandwidth which stabilizes cores like GBA for me at video_mode=13

flynnsbit wrote: ↑Fri Apr 15, 2022 9:00 pm I dont have the new firmware so not sure if that changes things. Overdrive is in the actual display's menu itself. Menu--Advanced -- Over Drive -- On and OD Gain 100, And yes, DVI turns off audio but will give it a bit extra bandwidth which stabilizes cores like GBA for me at video_mode=13

My display does not have an advanced menu.
It only have:

Brightness
Image
Color Temp.
Osd Setting.
Reset
Misc.

It's the hdmi/vga version. Maybe the override is only on the dual hdmi version?

Oh maybe, yeah mine is the dual HDMI. These are the ones I use. https://www.amazon.com/gp/product/B07R4VR9PR/

Thanks.
I'm temped to flash my firmware with the one posted in this thread. I might do it in the weekend.

FWIW - I received my unit and using the cable in the box it would not receive a signal from the MiSTer @ 1536p at all. I used a different (better quality) cable and now 1536p works. I had plugged it into a Retrotink 5x and the 1536p from that works so it may just be that the MiSTer doesn't quite output a strong enough signal and the cheap cable eats too much of it.

I got the dual Mini HDMI screen with the RTD2011 chipset. 480p is not supported. My MiSTer doesn't appear to provide enough power to the mUSB to power the screen when using the Terasic-supplied PSU either, but I didn't really expect it to.

Just received mine. Didn’t come with a power adapter. Anyone know if the center of the 12 barrel plug should be positive or negative?
Or can I simply use an iPad charger to power it via the micro USB port(don’t know how many amps is needed)?

Just received mine. In landscape orientation, the display has a single pixel width vertical black line:


Any suggestions on how to fix this? I’m happy to get my hands dirty

nizce wrote: ↑Sun Apr 24, 2022 8:38 pm Just received mine. Didn’t come with a power adapter. Anyone know if the center of the 12 barrel plug should be positive or negative?
Or can I simply use an iPad charger to power it via the micro USB port(don’t know how many amps is needed)?

Positive centre

I just ordered mine from the link in the first post, I hope it works well when it arrives.

nizce wrote: ↑Sun Apr 24, 2022 8:38 pm Just received mine. Didn’t come with a power adapter. Anyone know if the center of the 12 barrel plug should be positive or negative?
Or can I simply use an iPad charger to power it via the micro USB port(don’t know how many amps is needed)?

You can power it from mUSB, seems to need about 2.5 Amps.

jamesfmackenzie wrote: ↑Fri May 06, 2022 8:26 pm Just received mine. In landscape orientation, the display has a single pixel width vertical black line.

Any suggestions on how to fix this? I’m happy to get my hands dirty

Assuming this dead pixel line is present all the time, take a screen shot via MiSTer, if the dead pixel line is not present on the screenshot it is nearly always a hardware fault, not really much you can do yourself to fix. Contact the seller and ask for a replacement.

Any idea on how to change to English ? I’ve gone through each setting and can’t seem to find it ?

metalfacemark wrote: ↑Wed May 11, 2022 1:14 pm Any idea on how to change to English ? I’ve gone through each setting and can’t seem to find it ?

limi wrote: ↑Thu Sep 30, 2021 1:20 am Trigger the OSD → Select the [OSD] section (it’s an icon) → Select the first entry, which is the language selector → push up or down.