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Atari 7800 Display List Question


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I am reading the documentation on 7800 Display Lists and something stumbled me about 4 or 5 byte entries. How does the Maria chip know if it is a 4 or 5 byte entry? I am trying to formulate better ways to move objects around on screen and switching over to use Assembly and C. I am getting away from using another programming language.

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Maria knows from the second byte in the header. If bits 0..4 are all 0, it's either a 5-byte header or a display list terminator. Otherwise, if any of bits 0..4 are set it's a 4-byte header.

Funnily enough I'm thinking about going the other way. Everything I've done on the 7800 so far has been in assembler and I'm pondering giving 7800basic a try.

Edited by PCL
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