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Change bold code snippets to inline code blocks

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James Gregory 2013-12-31 17:12:29 +11:00
commit 3c76d884ef
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28-05.md
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@ -14,12 +14,12 @@ Listing 28.3 illustrates an efficient use of write mode 3 in conjunction
with read mode 1 and a Color Don't Care register setting of 0. The mask
in AL is passed directly to the VGA's bit mask (that's how write mode 3
works—see Chapter 4 for details). Because the VGA always returns 0FFH,
the single **AND** instruction loads the latches, and writes the value
the single `AND` instruction loads the latches, and writes the value
in AL, unmodified, to the VGA, where it is used to generate the bit
mask. This is more compact and register-efficient than using separate
instructions to read and write, although it is not necessarily faster by
cycle count, because on a 486 or a Pentium **MOV** is a 1-cycle
instruction, but **AND** with memory is a 3-cycle instruction. However,
cycle count, because on a 486 or a Pentium `MOV` is a 1-cycle
instruction, but `AND` with memory is a 3-cycle instruction. However,
given display memory wait states, it is often the case that the two
approaches run at the same speed, and the register that the above
approach frees up can frequently be used to save one or more cycles in