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Use backtick code blocks for syntax highlighting

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James Gregory 2013-12-31 11:38:48 +11:00
commit f658bfbb40
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03-08.md
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@ -70,64 +70,66 @@ timing.
**LISTING 3.6 LZTEST.ASM**
; Program to measure performance of code that takes longer than
; 54 ms to execute. (LZTEST.ASM)
;
; Link with LZTIMER.ASM (Listing 3.5). LZTIME.BAT (Listing 3.7)
; can be used to assemble and link both files. Code to be
; measured must be in the file TESTCODE; Listing 3.8 shows
; a sample file (LST3-8.ASM) which should be named TESTCODE.
;
; By Michael Abrash
;
mystack segment para stack ‘STACK'
db 512 dup(?)
mystack ends
;
Code segment para public ‘CODE'
assume cs:Code, ds:Code
extrn ZTimerOn:near, ZTimerOff:near, ZTimerReport:near
Startproc near
push cs
pop ds ;point DS to the code segment,
; so data as well as code can easily
; be included in TESTCODE
;
; Delay for 6-7 seconds, to let the Enter keystroke that started the
; program come back up.
;
mov ah,2ch
int 21h ;get the current time
mov bh,dh ;set the current time aside
DelayLoop:
mov ah,2ch
push bx ;preserve start time
int 21h ;get time
pop bx ;retrieve start time
cmp dh,bh ;is the new seconds count less than
; the start seconds count?
jnb CheckDelayTime ;no
add dh,60 ;yes, a minute must have turned over,
; so add one minute
CheckDelayTime:
sub dh,bh ;get time that's passed
cmp dh,7 ;has it been more than 6 seconds yet?
jb DelayLoop ;not yet
;
include TESTCODE ;code to be measured, including calls
; to ZTimerOn and ZTimerOff
;
; Display the results.
;
call ZTimerReport
;
; Terminate the program.
;
mov ah,4ch
int 21h
Start endp
Code ends
end Start
```nasm
; Program to measure performance of code that takes longer than
; 54 ms to execute. (LZTEST.ASM)
;
; Link with LZTIMER.ASM (Listing 3.5). LZTIME.BAT (Listing 3.7)
; can be used to assemble and link both files. Code to be
; measured must be in the file TESTCODE; Listing 3.8 shows
; a sample file (LST3-8.ASM) which should be named TESTCODE.
;
; By Michael Abrash
;
mystack segment para stack ‘STACK'
db 512 dup(?)
mystack ends
;
Code segment para public ‘CODE'
assume cs:Code, ds:Code
extrn ZTimerOn:near, ZTimerOff:near, ZTimerReport:near
Startproc near
push cs
pop ds ;point DS to the code segment,
; so data as well as code can easily
; be included in TESTCODE
;
; Delay for 6-7 seconds, to let the Enter keystroke that started the
; program come back up.
;
mov ah,2ch
int 21h ;get the current time
mov bh,dh ;set the current time aside
DelayLoop:
mov ah,2ch
push bx ;preserve start time
int 21h ;get time
pop bx ;retrieve start time
cmp dh,bh ;is the new seconds count less than
; the start seconds count?
jnb CheckDelayTime ;no
add dh,60 ;yes, a minute must have turned over,
; so add one minute
CheckDelayTime:
sub dh,bh ;get time that's passed
cmp dh,7 ;has it been more than 6 seconds yet?
jb DelayLoop ;not yet
;
include TESTCODE ;code to be measured, including calls
; to ZTimerOn and ZTimerOff
;
; Display the results.
;
call ZTimerReport
;
; Terminate the program.
;
mov ah,4ch
int 21h
Start endp
Code ends
end Start
```
As with the precision Zen timer, the program in Listing 3.6 is used by
naming the file containing the code to be timed TESTCODE, then