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640x200 atm hardware multicolor

PostPosted: 16 Jan 2012, 19:14
by justine
I take it that hardware multicolor means 64 colors ?

How are the pixels laid out ? 1 byte per pixel ? And at what address does this display start ?

Thanx in advance

Re: 640x200 atm hardware multicolor

PostPosted: 16 Jan 2012, 20:59
by lvd
hardware multicolor just means that each pixelbyte has its own attribute byte -- UNLIKE 6912 mode!

For atm 640x200 mode, 80x200 array of pixelbytes divided into odd and even ones. Even ones are in page #5 starting from #0000 displacement in linear order (40 bytes of line 0, then 40 bytes of line 1, etc.), odd ones are in the same page at displacement #2000. Every pixelbyte has its own attribute byte at the same displacement but in page #1. As usual, add 2 to every page number if bit3.#7FFD is 1.

Attribute byte is also different from 6912 one. There is no flash bit, but instead two bright bits: bit6 for ink (bits 2..0), bit 7 for paper (bits 5..3).

Re: 640x200 atm hardware multicolor

PostPosted: 17 Jan 2012, 07:30
by DimkaM
justine wrote:I take it that hardware multicolor means 64 colors ?

Мну тоже волнует эта тема, 640 конечна круто(10 страниц всё же), но 320||256 в самый раз.