Nestress (Use $2002/05 to set adr)

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Nestress (Use $2002/05 to set adr)

Post by Zeg » Sun Nov 21, 2004 10:00 pm

Hi, (Sorry for my bad english, i'm not speak english)

I'm building an emulator NES, and i testing this emulator with Nestress.

But i don't understand, the ppu test number 9 (Use $2002/05 to set adr).

Someone know, how that testing ?

Thank's in advance

PS : Sorry if you don't understand say me

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Joined: Sat Nov 13, 2004 6:25 am

Post by Muchaserres » Mon Nov 22, 2004 10:09 am

Well, first of, that test should be number 10 (counting from 1), be sure to be using Nestress lastest version (you can get it from the main page).

About that test, I'm not sure at all, but I guess it resets VRAM address by reading register 0x2002, and then sets the new address by writing twice to register 0x2005. Check Loopy's Scrolling texts for more info on how PPU I/O registers work.


Post by Guest » Mon Nov 22, 2004 2:35 pm

Thanks for you reply... :)

The PPU Test 8 (Read $2002 to reset latch) check if the toggle value (2005/6) is reseted.

I don't think, the PPU Test 9 (Use $2002/05 to set adr) do the same thing.

No ?

(I've a last version of Nestress, but I count the test from 0)
(And I already read the Loopy's Scrolling texts)

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