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/**
* Demonstration code for MCU 8051 IDE
*
* Create virtual multiplexed LED display
* [Main menu] -> [Virtual HW] -> [Open]
* and open file keypad_display.vhw .
* Then press F2 and F9 to start simulation.
*
* Notes:
* F9 - stop simulation
* F2 - shut down simulator
*
* @file keypad_display.c
*/
#include <8051.h>
#define USE_INLINE_ASM 1
static const char keypad[] = {
0xEF, 0xDF, 0xBF, 0x7F
};
static const char display_0[] = {
0xf9, 0x64, 0x70, 0x48
};
static const char display_1[] = {
0x59, 0x52, 0x42, 0x40
};
static const char display_2[] = {
0xf8, 0x40, 0x50, 0xc6
};
static const char display_3[] = {
0x79, 0xc0, 0x49, 0xc0
};
char state;
int row;
int main()
{
while(1) {
for(row=0; row<4; row++) {
P1=keypad[row];
#if USE_INLINE_ASM
// Inline assembler
_asm
mov _state, P1
_endasm;
#else
state=P1;
#endif
state&=0x0f;
state^=0x0f;
if(state & 1) {
state=0;
} else if(state & 2) {
state=1;
} else if(state & 4) {
state=2;
} else if(state & 8) {
state=3;
} else {
continue;
}
switch(row) {
case 0:
P3=display_0[state];
break;
case 1:
P3=display_1[state];
break;
case 2:
P3=display_2[state];
break;
case 3:
P3=display_3[state];
break;
}
}
}
}
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