Example 5 Pushbutton Switches: S1 and S2

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Example 5Pushbutton Switches S1 and S2

• Lecture L3.1

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miniDragon
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(No Transcript)
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Pushbutton Switches S1 and S2
(PORTAD0 0x10) 0
TRUE if S1 is closed
(PORTAD0 0x08) 0
TRUE if S2 is closed
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Example 5a
// Example 5a Pushbutton Switches include
lthidef.hgt / common defines and macros
/ include ltmc9s12dp256.hgt / derivative
information / include "main_asm.h" / interface
to the assembly module / pragma LINK_INFO
DERIVATIVE "mc9s12dp256b" void main(void)
PLL_init() // set system clock frequency to 24
MHz seg7_enable() // enable 7-segment
display ATD0DIEN 0x18 // enable S1
and S2 while(1) if((PORTAD0 0x10)
0) seg7dec(1) else
seg7_off() if((PORTAD0 0x08) 0)
seg7dec(2) else seg7_off()

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Example 5b
// Example 5b Pushbutton Switches using C
function calls include lthidef.hgt / common
defines and macros / include ltmc9s12dp256.hgt
/ derivative information / include
"main_asm.h" / interface to the assembly module
/ pragma LINK_INFO DERIVATIVE
"mc9s12dp256b" void main(void)
PLL_init() // set system clock frequency to 24
MHz seg7_enable() // enable 7-segment
display SW12_enable() // enable S1 and
S2 while(1) if(SW1_down())
seg7dec(1) else seg7_off()
if(SW2_down()) seg7dec(2) else
seg7_off()
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Example 5
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Example 5c
// Example 5c Pushbutton Switches - Problem
5.3 include lthidef.hgt / common defines and
macros / include ltmc9s12dp256.hgt /
derivative information / include "main_asm.h"
/ interface to the assembly module / pragma
LINK_INFO DERIVATIVE "mc9s12dp256b" void
main(void) PLL_init() // set system clock
frequency to 24 MHz seg7_enable() //
enable 7-segment display SW12_enable()
// enable S1 and S2 while(1)
while(SW1_down()) seg7dec(1)
seg7_off() while(SW2_down())
seg7dec(2) seg7_off()