HD7850 now compatible with 15khz ?

[Dalba]

Hello,
making some searches, i "accidentally" fell on this topic : http://shmups.system11.org/viewtopic.php?f=6&t=23303&start=0 where a guy named kamilz said that he could use successfully latest soft15khz (build 52) with his hd7850 on Windows7 x64.
Can someone confirm this ? If true, would it be possible to adapt calamity's driver to benefit from hd 7850 ? I used to think that crt_emudriver and soft15khz were using same method to add modelines... but i may be wrong !
It would be a huge step forward to be able to use a hd7850 as it would allow to use dx11 based emulators and future dx12 developments (hd7850 is already dx12 compatible).

[Calamity]

The poster says he got 240p using the CRU program, which creates modes through a custom edid. This method works but is too limited to be usable for emulation in the way we do it with GroovyMAME.

Soft-15kHz as well as CRT Emudriver use ATI registry modelines that will not work starting from the HD 5000 family and anything later. I know why this happens because I've reverse-engineered the driver.

If you install Soft-15kHz on newer cards the modes do show up so you may mistakenly think it has worked, but the timings will be overridden by unusable standard vesa timings.

You can count on the fact that when modern cards get finally supported, it will be known.

[Dalba]

Thanks for your answer, you just save me some money as i was ready to buy one and make tests.
I just hope we'll get one day groovymame to work with "moderns" graphic cards...

[kamilz]

I edited the message on the forum which says Soft15KHZ works with ATI 7850 HD card.
As you said, it doesn't work.

CRU is OK but limited exactly as you said again.

Can you give more info about "Soft-15kHz as well as CRT Emudriver use ATI registry modelines that will not work starting from the HD 5000 family and anything later. I know why this happens because I've reverse-engineered the driver."

I wonder what's going on the new drivers. Thanks.

[Calamity]

Hi kamilz,

Can you give more info about "Soft-15kHz as well as CRT Emudriver use ATI registry modelines that will not work starting from the HD 5000 family and anything later. I know why this happens because I've reverse-engineered the driver."

From what I've seen, starting with the HD 5000 family they replaced the old C display abstraction layer by a new C++ one for the new chipsets. The old layer was left there for legacy cards. So a completely different layer is used depending on the chipset. The old registry modelines (Soft-15khz, CRT Emudriver) were read in the old layer. They're not even read if you're using an HD 5xxx or newer card.