Normal quotes

29-06.md

@@ -2,27 +2,27 @@
   [Previous](29-05.html)   [Table of Contents](index.html)   [Next](30-01.html)
   ------------------------ --------------------------------- --------------------
 
-Does that do it for color selection? Yes and no. For the EGA, we’ve
+Does that do it for color selection? Yes and no. For the EGA, we've
 covered the whole of color selection—but not so for the VGA. The VGA can
-emulate everything we’ve discussed, but actually performs one 4-bit to
+emulate everything we've discussed, but actually performs one 4-bit to
 8-bit translation (except in 256-color modes, where all 256 colors are
 simultaneously available), followed by yet another translation, this one
-8-bit to 18-bit. What’s more, the VGA has the ability to flip instantly
-through as many as 16 16-color sets. The VGA’s color selection
+8-bit to 18-bit. What's more, the VGA has the ability to flip instantly
+through as many as 16 16-color sets. The VGA's color selection
 capabilities, which are supported by another set of BIOS functions, can
-be used to produce stunning color effects, as we’ll see when we cover
+be used to produce stunning color effects, as we'll see when we cover
 them starting in Chapter 33.
 
 ### Modifying VGA Registers {#Heading7}
 
 EGA registers are not readable. VGA registers are readable. This
 revelation will not come as news to most of you, but many programmers
-still insist on setting entire VGA registers even when they’re modifying
+still insist on setting entire VGA registers even when they're modifying
 only selected bits, as if they were programming the EGA. This comes to
 mind because I recently received a query inquiring why write mode 1 (in
 which the contents of the latches are copied directly to display memory)
-didn’t work in Mode X. (I’ll go into Mode X in detail later in this
-book.) Actually, write mode 1 does work in Mode X; it didn’t work when
+didn't work in Mode X. (I'll go into Mode X in detail later in this
+book.) Actually, write mode 1 does work in Mode X; it didn't work when
 this particular correspondent enabled it because he did so by writing
 the value 01H to the Graphics Mode register. As it happens, the write
 mode field is only one of several fields in that register, as shown in
@@ -45,29 +45,29 @@ setting the VGA to write mode 1, do this:
     out   dx,al            ;set write mode 1
 
 This approach is more of a nuisance than simply setting the whole
-register, but it’s safer. It’s also slower; for cases where you must set
+register, but it's safer. It's also slower; for cases where you must set
 a field repeatedly, it might be worthwhile to read and mask the register
 once at the start, and save it in a variable, so that the value is
 readily available in memory and need not be repeatedly read from the
 port. This approach is especially attractive because **IN**s are much
 slower than memory accesses on 386 and 486 machines.
 
-Astute readers may wonder why I didn’t put a delay sequence, such as
+Astute readers may wonder why I didn't put a delay sequence, such as
 **JMP \$+2**, between the **IN** and **OUT** involving the same
 register. There are, after all, guidelines from IBM, specifying that a
 certain period should be allowed to elapse before a second access to an
 I/O port is attempted, because not all devices can respond as rapidly as
-a 286 or faster CPU can access a port. My answer is that while I can’t
-guarantee that a delay isn’t needed, I’ve never found a VGA that
+a 286 or faster CPU can access a port. My answer is that while I can't
+guarantee that a delay isn't needed, I've never found a VGA that
 required one; I suspect that the delay specification has more to do with
 motherboard chips such as the timer, the interrupt controller, and the
-like, and I sure hate to waste the delay time if it’s not necessary.
-However, I’ve never been able to find anyone with the definitive word on
+like, and I sure hate to waste the delay time if it's not necessary.
+However, I've never been able to find anyone with the definitive word on
 whether delays might ever be needed when accessing VGAs, so if you know
 the gospel truth, or if you know of a VGA/processor combo that does
 require delays, please let me know by contacting me through the
-publisher. You’d be doing a favor for a whole generation of graphics
-programmers who aren’t sure whether they’re skating on thin ice without
+publisher. You'd be doing a favor for a whole generation of graphics
+programmers who aren't sure whether they're skating on thin ice without
 those legendary delays.
 
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