Normal quotes

34-05.md

@@ -4,25 +4,25 @@
 
 Yet another and somewhat odder workaround is that of using only 128 DAC
 locations and page flipping. (Page flipping in 256-color modes involves
-using the VGA’s undocumented 256-color modes; see Chapters 31, 43, and
-47 for details.) In this mode of operation, you’d first display page 0,
-which is drawn entirely with colors 0-127. Then you’d draw page 1 to
+using the VGA's undocumented 256-color modes; see Chapters 31, 43, and
+47 for details.) In this mode of operation, you'd first display page 0,
+which is drawn entirely with colors 0-127. Then you'd draw page 1 to
 look just like page 0, except that colors 128-255 are used instead.
-You’d load DAC locations 128-255 with the next cycle settings for the
-128 colors you’re using, then you’d switch to display the second page
+You'd load DAC locations 128-255 with the next cycle settings for the
+128 colors you're using, then you'd switch to display the second page
 with the new colors. Then you could modify page 0 as needed, drawing in
 colors 0-127, load DAC locations 0-127 with the next color cycle
 settings, and flip back to page 0.
 
 The idea is that you modify only those DAC locations that are not used
 to display any pixels on the current screen. The advantage of this is
-*not*, as you might think, that you don’t generate garbage on the screen
+*not*, as you might think, that you don't generate garbage on the screen
 when modifying undisplayed DAC locations; in fact, you do, for a spot of
 interference will show up if you set a DAC location, displayed or not,
 during display time. No, you still have to wait for vertical sync and
 load only during vertical blanking before loading the DAC when page
 flipping with 128 colors; the advantage is that since none of the DAC
-locations you’re modifying is currently displayed, you can spread the
+locations you're modifying is currently displayed, you can spread the
 loading out over two or more vertical blanking periods—however long it
 takes. If you did this without the 128-color page flipping, you might
 get odd on-screen effects as some of the colors changed after one frame,
@@ -36,16 +36,16 @@ on-screen colors by cycling colors *as a frame is displayed*, so that
 the color set changes from scan line to scan line down the screen.
 
 The possibilities are endless. However, were I to be writing 256-color
-software that used color cycling, I’d find out how many colors could be
+software that used color cycling, I'd find out how many colors could be
 cycled after the start of vertical sync on the slowest computer I
-expected the software to run on, I’d lop off at least 10 percent for a
-safety margin, and I’d structure my program so that no color cycling set
+expected the software to run on, I'd lop off at least 10 percent for a
+safety margin, and I'd structure my program so that no color cycling set
 exceeded that size, interleaving several color cycling sets if
 necessary.
 
-That’s what *I’d* do. Don’t let yourself be held back by my limited
+That's what *I'd* do. Don't let yourself be held back by my limited
 imagination, though! Color cycling may be the most complicated of all
-the color control techniques, but it’s also the most powerful.
+the color control techniques, but it's also the most powerful.
 
 ### Odds and Ends {#Heading9}
 
@@ -54,7 +54,7 @@ loading the DAC, the Write Index register wraps back from 255 to 0, and
 likewise when you load a block of registers through the BIOS. So far as
 I know, this is a characteristic of the hardware, and should be
 consistent; also, Richard Wilton documents this behavior for the BIOS in
-the VGA bible, *Programmer’s Guide to PC Video Systems, Second Edition*
+the VGA bible, *Programmer's Guide to PC Video Systems, Second Edition*
 (Microsoft Press), so you should be able to count on it. Not that I see
 that DAC index wrapping is especially useful, but it never hurts to
 understand exactly how your resources behave, and I never know when one
@@ -63,7 +63,7 @@ quirk.
 
 #### The DAC Mask {#Heading10}
 
-There’s one register in the DAC that I haven’t mentioned yet, the DAC
+There's one register in the DAC that I haven't mentioned yet, the DAC
 Mask register at 03C6H. The operation of this register is simple but
 powerful; it can mask off any or all of the 8 bits of pixel information
 coming into the DAC from the VGA. Whenever a bit of the DAC Mask
@@ -83,7 +83,7 @@ The DAC can be read directly, via the DAC Read Index register at 3C7H
 and the DAC Data register at 3C9H, in much the same way as it can be
 written directly by way of the DAC Write Index register—complete with
 autoincrementing the DAC Read Index register after every three reads.
-Everything I’ve said about writing to the DAC applies to reading from
+Everything I've said about writing to the DAC applies to reading from
 the DAC. In fact, reading from the DAC can even cause snow, just as
 loading the DAC does, so it should ideally be performed during vertical
 blanking.
@@ -113,12 +113,12 @@ very much symmetric with setting the DAC.
 
 And so, at long last, we come to the end of our discussion of color
 control on the VGA. If it has been more complex than anyone might have
-imagined, it has also been most rewarding. There’s as much obscure but
+imagined, it has also been most rewarding. There's as much obscure but
 very real potential in color control as there is anywhere on the VGA,
-which is to say that there’s a very great deal of potential indeed. Put
+which is to say that there's a very great deal of potential indeed. Put
 color cycling or color paging together with the page flipping and image
-drawing techniques explored elsewhere in this book, and you’ll leave the
-audience gasping and wondering “How the heck did they *do* that?”
+drawing techniques explored elsewhere in this book, and you'll leave the
+audience gasping and wondering "How the heck did they *do* that?"
 
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