Home » Forum » MSX Talk » General discussion » MSX2 intro animation

MSX2 intro animation

By RobertoC

Supporter (5)

RobertoC's picture

07-06-2023, 18:05

Hello,
Does anyone know where to find a technical description of how the MSX2 boot animation is done?

Thank you
-
Roberto

Login or register to post comments

By PingPong

Enlighted (4155)

PingPong's picture

07-06-2023, 21:03

It's easy. It does work in screen 6.
The Vdp vertical scroll register is used to scroll the logo
there is a screen split on the bottom of the logo.
when the screen split occours (via vdp horizontal retrace interrupt) the visible page is switched and the rest of the screen is displayed in background color.
so the logo appear to "pop" from the middle bottom of the screen

More interesting is the MSX2+ and TurboR logo

By RobertoC

Supporter (5)

RobertoC's picture

07-06-2023, 22:20

Thank you for the explanation. But reading I realized my mistake: I meant the MSX2+ intro -
where two halves of the logo scroll horizontally to stop in the center.
I think there is a page change there too, but it seems to me too expensive to do it for all lines.

--
r.

By Daemos

Prophet (2165)

Daemos's picture

08-06-2023, 13:26

Propably also doing a screen split on each line where the scroll registers are set. At each frame the registers are being changed until the logo is one whole. No changes in the vram required.

By iamweasel2

Paladin (722)

iamweasel2's picture

08-06-2023, 17:57

If one wants to change the graphic in the boot, where the data pattern is stored?

By mars2000you

Enlighted (6555)

mars2000you's picture

08-06-2023, 18:21

On MSX2, it's generally in the Sub-ROM.

It's more complicated on MSX2+ and MSX turbo R, I think it's in the Kanji driver ROM.

By mars2000you

Enlighted (6555)

mars2000you's picture

08-06-2023, 18:26

See https://www.msx.org/forum/msx-talk/hardware/msx-logo-rom-change

By Briqunullus

Paladin (750)

Briqunullus's picture

08-06-2023, 18:56

mars2000you wrote:

It's more complicated on MSX2+ and MSX turbo R, I think it's in the Kanji driver ROM.

I have seen it being called the optrom, or opening rom. If have no idea what optrom stands for. Anybody? And yes, this rom is only a few kilobytes, so it can be integrated into the Kanji rom. However, I have seen this on MSX2+. If I remember correctly, this isn't the case on turboR.