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Working on Plantronics Viewer

MOVSW is an even bigger friend, since even on 8088 it's faster. Each MOVSB takes 16 clocks, so to move two bytes that's 32 clocks not counting opcode fetching. MOVSW takes 24 clocks so you get two bytes moved for 8 less clocks every loop. Just cut your CX in half.

Code:
    mov   si, Data
    mov   ax,0B800h
    mov   es,ax
    xor   di,di

    mov   cx,4000
    rep   movsw

Ohhhh... can't wait to try it. 384k clocks to move a single page of 640x200x1 bit, so 768k clocks to move a single Plantronics frame. Is that .161 ms? Doesn't seem right? What am I doing wrong with my math? Doesn't feel like a 60 Hz flicker of two Plantronics screens would be possible then.

Provides even bigger benefits on the 8086 and up, since on those machines with 16 bit or wider busses you're talking 16 clocks to move 1 byte vs 16 clocks to move two bytes

See the timings here:
I NEEDED this website - I have been looking far and wide for something like this!!!


That's my own reference I created for my own projects made off the commonly shared PCGPE.TXT by Mark Feldmen's, but with filtering by processor type. Fun project in and of itself since it's a monolithic web page with HTML and CSS doing all the heavy lifting and little to no scripting involved.

You can do the same with stosw, just be sure AH is the same as AL when clearing the page.
 
Ok, so I am trying to figure out how to use the 640x200x4 mode and turning on the color burst to see if I can make a cool image. Thinking through the composite mode I feel like the best I can do is 96 colors, but somehow that doesn't feel right. Regardless I have 4 colors and we know there are 16 bit patterns for any two color combination. I have 4 colors and so I can make 6 unique sets (for standard pal, Black/White, Black/Cyan, Black/Magenta, Cyan/White, Cyan/Magenta, Magenta/White) so 16* 6 = 96. Is that all that will work to make artifact colors? Would Magenta, Cyan, White, Magenta for example make a different artifact color? It was easy in the 16 color mode because only two pixels were involved in each artifact color. In 640x200 it is also easy because it is only 2 possible colors per 4 pixels. Now that I have 4 colors per pixel the total number of permutations is 256 for every 4 pixels. I just realized as I type this that I am in the same boat as the 320x200x16 mode - we have 256 permutations of each 2 pixels. So I would end up with a color resolution of 160x200x256. Hmm - wonder if it is still worth doing.
 
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