Normal quotes

23-03.md

@@ -4,7 +4,7 @@
 
 #### Linear Planes and True VGA Modes {#Heading6}
 
-The VGA’s memory is organized as four 64K planes. Each of these planes
+The VGA's memory is organized as four 64K planes. Each of these planes
 is a linear bitmap; that is, each byte from a given plane controls eight
 adjacent pixels on the screen, the next byte controls the next eight
 pixels, and so on to the end of the scan line. The next byte then
@@ -13,46 +13,46 @@ end of the screen.
 
 The VGA adds a powerful twist to linear addressing; the logical width of
 the screen in VGA memory need not be the same as the physical width of
-the display. The programmer is free to define all or part of the VGA’s
+the display. The programmer is free to define all or part of the VGA's
 large memory map as a logical screen of up to 4,080 pixels in width, and
 then use the physical screen as a window onto any part of the logical
-screen. What’s more, a virtual screen can have any logical height up to
+screen. What's more, a virtual screen can have any logical height up to
 the capacity of VGA memory. Such a virtual screen could be used to store
 a spreadsheet or a CAD/CAM drawing, for instance. As we will see
 shortly, the VGA provides excellent hardware for moving around the
-virtual screen; taken together, the virtual screen and the VGA’s smooth
+virtual screen; taken together, the virtual screen and the VGA's smooth
 panning capabilities can generate very impressive effects.
 
 All four linear planes are addressed in the same 64K memory space
 starting at A000:0000. Consequently, there are four bytes at any given
 address in VGA memory. The VGA provides special hardware to assist the
 CPU in manipulating all four planes, in parallel, with a single memory
-access, so that the programmer doesn’t have to spend a great deal of
+access, so that the programmer doesn't have to spend a great deal of
 time switching between planes. Astute use of this VGA hardware allows
 VGA software to as much as quadruple performance by processing the data
 for all the planes in parallel.
 
 Each memory plane provides one bit of data for each pixel. The bits for
 a given pixel from each of the four planes are combined into a nibble
-that serves as an address into the VGA’s palette RAM, which maps the one
+that serves as an address into the VGA's palette RAM, which maps the one
 of 16 colors selected by display memory into any one of 64 colors, as
 shown in Figure 23.1. All sixty-four mappings for all 16 colors are
-independently programmable. (We’ll discuss the VGA’s color capabilities
+independently programmable. (We'll discuss the VGA's color capabilities
 in detail starting in Chapter 33.)
 
 The VGA BIOS supports several graphics modes (modes 4, 5, and 6) in
 which VGA memory appears not to be organized as four linear planes.
 These modes exist for CGA compatibility only, and are not true VGA
 graphics modes; use them when you need CGA-type operation and ignore
-them the rest of the time. The VGA’s special features are most powerful
+them the rest of the time. The VGA's special features are most powerful
 in true VGA modes, and it is on the 16-color true-VGA modes (modes 0DH
 (320x200), 0EH (640x200), 10H (640x350), and 12H (640x480)) that I will
 concentrate in this part of the book. There is also a 256-color mode,
 mode 13H, that appears to be a single linear plane, but, as we will see
-in Chapters 31-34 and 47-49 of this book, that’s a polite fiction—and
+in Chapters 31-34 and 47-49 of this book, that's a polite fiction—and
 discarding that fiction gives us an opportunity to unleash the power of
-the VGA’s hardware for vastly better performance. VGA text modes, which
-feature soft fonts, are another matter entirely, upon which we’ll touch
+the VGA's hardware for vastly better performance. VGA text modes, which
+feature soft fonts, are another matter entirely, upon which we'll touch
 from time to time.
 
 ![](images/23-01.jpg)\
@@ -60,7 +60,7 @@ from time to time.
 
 With that background out of the way, we can get on to the sample VGA
 program shown in Listing 23.1. I suggest you run the program before
-continuing, since the explanations will mean far more to you if you’ve
+continuing, since the explanations will mean far more to you if you've
 seen the features in action.
 
 **LISTING 23.1 L23-1.ASM**