[Help Needed] My work on an Apple Studio Display M7768 (The Transparent ADC CRT)

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mega calibrator

New Tinkerer
Mar 12, 2025
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Hello all,

I'm the dev of DDC-for-CRT and a similar app for the 21" studio display (blueberry/graphite gumdrop). @getwellkel reached out and helped test a small tool for turning the monitor on and off. Find it here.

I hope to implement a way to control geometry, however it will take some experimenting since those controls are done via the USB connection. Anyone who is able to help with testing please let me know
 
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panettondoro

New Tinkerer
Sep 7, 2024
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I've been looking into figuring out if I can modify my display's geometry recently and I may have found another method of controlling power mode that doesn't require python. It's a program called ControlMyMonitor and it really does just that. It's a portable .exe that doesn't have all the fuss that monitorcontrol.exe requires.

View attachment 20626
I found that VCP code at position D6 corresponds to the power mode, setting this to 1 results in a wakeup, setting this to 4 results in a soft off. I don't know what 0, 2 or 3 do, as nothing happens when I try to write those values.

This program offers a pretty handy GUI for debugging and offers command line inputs as well, so you can automate this via a power shell script as well. I'll probably get around to migrating my startup script to this eventually, my monitorcontrol.exe setup is fine for now.

I found this after going down a rabbit hole of reading the monitorcontrol.exe source code, Virtual Control Panel (VCP) codes, dxva2.dll and some other things, it's all a bit of a blur now. My long term goal is to be able to modify the monitor's geometry, as the letterboxing on my unit is distracting. Ideally, I'd like to use a program like mega-calibrator's DDC-for-CRT project to adjust my picture's position. My current setup uses the ADC jasondoesitall board, receiving video from a DP to VGA converter sourced from an RTX 3060 Ti and USB data from a USB-B connector leading to my mobo in addition to DC power. Looking into conversations on this reddit post related to the DDC-for-CRT project, one of the replies allude to using both a converter and a mobo VGA port, to which OP replies:

I will reach out to them to see if they have any insight to the funny business that is the ADC CRT Studio Display. I'm hoping that there is a way to 'unlock' additional VCP codes for the monitor but I feeling that I'm going to be SOL there. Based on what I've researched, I'm afraid that in order to accomplish this, a custom dxva2.dll might be required to communicate with the studio display. This is all too in the weeds for me, so I'm hoping someone else might be more educated in this type of thing than me.

Please let me know if you have any insights on VCP codes or geometry control in general, thanks all
Super neat find @getwellkel! That is certainly a much better way to debug the monitor!

If I understood the scope of your reply correctly, there shouldn't be any need for a custom dxva2.dll file, as I believe that the file simply handles DDC requests made in higher level contexts. If ControlMyMonitor lets you specify VCP codes arbitrarily, you should be able to easily edit the fields which control the geometry. Page 30 of this document contains the (rather extensive!) full list of codes.

However, with that said, I believe that the Studio Display manages its geometry settings through the USB interface, and not I2C. Another user on Reddit recently tried doing something similar and they discovered that the Studio Display only responds to a limited set of commands on the I2C interface, namely, just the D6 feature.

To correctly interface with USB, you might have to take a look at winddcutil, which is a Windows fork of ddcutil or do something like @Titania did, which is using a separate linux device (either virtual or physical) to run ddcutil on.
 
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panettondoro

New Tinkerer
Sep 7, 2024
9
11
3
Hello all,

I'm the dev of DDC-for-CRT and a similar app for the 21" studio display (blueberry/graphite gumdrop). @getwellkel reached out and helped test a small tool for turning the monitor on and off. Find it here.

I hope to implement a way to control geometry, however it will take some experimenting since those controls are done via the USB connection. Anyone who is able to help with testing please let me know
Sorry, just saw your reply! Super neat that you're working on this! I can't help too much with this since I haven't managed to make my Studio Display work yet, but I can link some useful resources!
 

beanlette

New Tinkerer
May 4, 2022
2
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essex, uk
hi everyone, ive following this thread recently and thought i would say something rather than quietly benefitting... i got one of these monitors and made jason's adapter in 2022 thanks to @fehervaria sending me a couple ADC connectors, when i then had my own share of issues controlling the monitor from windows for a few years... until quite recently when @panettondoro pointed me here. i'm glad we all seem to have found each other at the right time. good work everyone!! i'm so happy these monitors are being used again~

i'd also like to provide a solution to an issue i personally had where, when i tried to just 'second screen only' the studio display, windows would default to an unsupported mystery resolution and frame rate, causing the monitor to turn off, where i then of course would not be able to see anything to change it back to a supported resolution again. the way i got around this (and maybe i am missing something obvious) was by using a remote desktop mobile app like google's remote desktop to view the 'off' screen, and choosing a supported set of options again so the monitor would power back on. quite silly but it worked :]

Hello everyone, with some extensive testing help from @getwellkel the app is now complete and functional!

Find the download here

works like magic!!! cannot thank you for this @mega calibrator, i had no luck controlling brightness or position or anything with WinI2C, monitorcontrol, or controlmymonitor, so this is a miracle program to me.

not to immediately spring an issue at you... but the controls to power off and on the display i see in the readme screenshot don't appear for me. i'd assume this to be because of my minidp adapter, however, i am still able to use WinI2C to power the monitor on just fine.

is there perhaps anyway to somehow integrate whatever WinI2C uses for it's power on and off signal into adccrtgui? for reference, i am using an official apple minidisplayport to vga adapter. it would be wonderful to everything in one package!
 

mega calibrator

New Tinkerer
Mar 12, 2025
3
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3
not to immediately spring an issue at you... but the controls to power off and on the display i see in the readme screenshot don't appear for me. i'd assume this to be because of my minidp adapter, however, i am still able to use WinI2C to power the monitor on just fine.

is there perhaps anyway to somehow integrate whatever WinI2C uses for it's power on and off signal into adccrtgui? for reference, i am using an official apple minidisplayport to vga adapter. it would be wonderful to everything in one package!
were you able to use monitorcontrol (python) to toggle the power? or only WinI2C ? adccrtgui uses the former