Introduction: How to Make a Digital Clock Kit Based on Atmel
This digtial clock kit comes with below features and functions:
Features
• Digital clock
• Counter
• Time alarm
• Stopwatch
Buttons
• S1: function selection button
• S2: extend function button
• S3: adjustment button
Functions:
Clock setting: Press S1 once,you will see clock display flashing, Press S2 once to add 1 hour, Press S3 one to add 1 minute.
Alarm setting: Press S1 twice,you will see colon keep light on, Press S2 once to add 1hour, Press S3 once to add 1 minute. It will turn off alarm when hour value over 23 and you will see --ï¼--ï¼--. Alarm will keep the buzzer on for 3 seconds.
Counter setting: Press S1 three times, you will see colon keep off and number show 0. Press S2 to select digit from lower end to higher end, then press S3 to add 1. It will start to count when you press S2 6th times.
Stopwatch: Press S1 four times, you will see 00ï¼00ï¼00, colon keep on, press S2 once to start stopwatch, press S2 again to stop it. Press S3 to clear numbers.
<iframe width="420" height="315" src="http://www.youtube.com/embed/3VZpj4x8xc8" frameborder="0" allowfullscreen></iframe>
Step 1: All Materials You Need for This Kits
Here are the components you will need for this clock kit:
1 AT89C2051 U2
2 78L05 U1
3 12MHz Oscillator X3
4 2 digit 7segment display LED1
5 2 digit 7segment display LED2
6 2 digit 7segment display LED3
7 LED D2
8 LED D3
9 LED D4
10 LED D5
11 Buzzer U7
12 CAP 30pF C1
13 CAP 30pF C2
14 CAP 0.1uF (104) C3
15 CAP 0.1uF (104) C4
16 CAP 10uF C5
17 CAP 100uF C6
18 PNP 9012 Q1
19 PNP 9012 Q2
20 PNP 9012 Q3
21 PNP 9012 Q4
22 PNP 9012 Q5
23 PNP 9012 Q6
24 PNP 9012 Q7
25 Button S1
26 Button S2
27 BUTTON S3
28 Resistor 220 Ohm R1
29 Resistor 220 Ohm R2
30 Resistor 220 Ohm R3
31 Resistor 220 Ohm R4
32 Resistor 220 Ohm R5
33 Resistor 220 Ohm R10
34 Resistor 220 Ohm R11
35 Resistor 1K Ohm R12
36 Resistor 1K Ohm R13
37 Resistor 1K Ohm R14
38 Resistor 1K Ohm R15
39 Resistor 1K Ohm R16
40 Resistor 1K Ohm R17
41 Resistor 1K Ohm R18
42 Resistor 5.1K Ohm R19
43 Resistor 2K Ohm R7
44 Resistor 2K Ohm R8
45 Resistor 10K Ohm R6
46 2 pin connector J1
47 2 pin connector J2
48 2 pin connector J3
49 20pin DIP socket -
50 PCB 50mmx105mm -
All the parts can be found at here:
http://engineeringshock.com/6-digit-atmel-digital-clock-p-72.html?zenid=vrvei88auo6df1j11uoegk4s56
Step 2: Circuit Schematic and PCB
here is the schematic and PCB design
Step 3: A Sample of Source Code(C Language)
#include<REG2051.H>
code senen_seg[10]={0x81,0xe7,0x92,0xa2,0xe4,0xa8,0x88,0xe3,0x80,0xa0};
bit key1_enter=0,key2_enter=0,key3_enter=0,countdown_mark=0,stopwatch_mark=0,count_mark=0,bell_mark=0;
unsigned char program=0,program_variable=0,count_bit=0,count=0;
unsigned char hour=10,minute=10,second=0;
unsigned char delayed_hour=22,delayed_minute=10,delayed_second=0;
unsigned char count_hour=0,count_minute=0,count_second=0;
unsigned int count_time=0,count_count=0;
void delay(unsigned int t)
{
unsigned int i,j;
for(i=0;i<t;i++)
for(j=0;j<10;j++)
;
}
void time0_init(void){
EA=0;
TR0=0;
TMOD=0x02;
TH0=0x4;
TL0=0x4;
ET0=1;
TR0=1;
EA=1;
}
static void timer0_isr(void) interrupt TF0_VECTOR using 1
{
count_time++;
if(count_time>=4020){
count_time=0;
second++;
if(second>=60){
second=0;
minute++;
if(minute>=60){
minute=0;
hour++;
if(hour>=24)hour=0;
}
}
}
if(delayed_hour==hour && delayed_minute==minute && second<4) P3_7=0;
else P3_7=1;
if(countdown_mark==1){
count_count++;
if(count_count>=4000 && (count_second!=0|count_minute!=0|count_hour!=0)){
count_count=0;
count_second--;
if(count_second>=60){
count_second=59;
count_minute--;
if(count_minute>=60){
count_minute=59;
count_hour--;
if(count_hour>=100) count_hour=99;
}
}
}
if(count_second==0&&count_minute==0&&count_hour==0&&count_count<=12000) P3_7=0;
else P3_7=1;
if(count_count>=15000) count_count=14000;
}
if(stopwatch_mark==1){ count_count++;
if(count_count>=40){
count_count=0;
count_second++;
if(count_second>=100){
count_second=0;
count_minute++;
if(count_minute>=60){
count_minute=0;
count_hour++;
if(count_hour>=60) count_hour=0;
}
}
}
}
}
unsigned char show_key (void){
unsigned char x=0,y=0;
switch (program){
case 0: P1&=senen_seg[second%10];
break;
case 1: if(count_time>=2000) P1&=senen_seg[second%10];
break;
case 2: if(delayed_hour==24) P1=0xfe;
else P1&=senen_seg[delayed_second%10];
break;
case 3: if(count_bit>=0) P1&=senen_seg[count_second%10];
else P1=0xff;
break;
case 4: P1&=senen_seg[count_second%10];
break;
case 5: P1&=senen_seg[count_second%10];
break;
}
P3_3=0;
delay(10);
if(P3_5==0){
key1_enter=1;
if(count<=254)count++;
}
if(P3_4==0) key2_enter=1;
if(P3_2==0) key3_enter=1;
P3_3=1;
P1|=0xff;
switch (program){
case 0: P1&=senen_seg[second/10];
break;
case 1: if(count_time>=2000) P1&=senen_seg[second/10];
break;
case 2: if(delayed_hour==24) P1=0xfe;
else P1&=senen_seg[delayed_second/10];
break;
case 3: if(count_bit>=1) P1&=senen_seg[count_second/10];
else P1=0xff;
break;
case 4: P1&=senen_seg[count_second/10];
break;
case 5: P1&=senen_seg[count_second/10];
break;
}
P3_1=0;
delay(10);
P3_1=1;
P1|=0xff;
switch (program){
case 0: P1&=senen_seg[minute%10];
break;
case 1: if(count_time>=2000) P1&=senen_seg[minute%10];
break;
case 2: if(delayed_hour==24) P1=0xfe;
else P1&=senen_seg[delayed_minute%10];
break;
case 3: if(count_bit>=2) P1&=senen_seg[count_minute%10];
else P1=0xff;
break;
case 4: P1&=senen_seg[count_minute%10];
break;
case 5: P1&=senen_seg[count_minute%10];
break;
}
P3_2=0;
delay(10);
P3_2=1;
P1|=0xff;
switch (program){
case 0: P1&=senen_seg[minute/10];
break;
case 1: if(count_time>=2000) P1&=senen_seg[minute/10];
break;
case 2: if(delayed_hour==24) P1=0xfe;
else P1&=senen_seg[delayed_minute/10];
break;
case 3: if(count_bit>=3) P1&=senen_seg[count_minute/10];
else P1=0xff;
break;
case 4: P1&=senen_seg[count_minute/10];
break;
case 5: P1&=senen_seg[count_minute/10];
break;
}
P3_5=0;
delay(10);
P3_5=1;
P1|=0xff;
switch (program){
case 0: P1&=senen_seg[hour%10];
break;
case 1: if(count_time>=2000) P1&=senen_seg[hour%10];
break;
case 2: if(delayed_hour==24) P1=0xfe;
else P1&=senen_seg[delayed_hour%10];
break;
case 3: if(count_bit>=4) P1&=senen_seg[count_hour%10];
else P1=0xff;
break;
case 4: P1&=senen_seg[count_hour%10]; break;
case 5: P1&=senen_seg[count_hour%10];
break;
}
P3_0=0;
delay(10);
if(P3_4==1 && key2_enter==1){
x=3; key2_enter=0;
}
P3_0=1;
P1|=0xff;
switch (program){
case 0: P1&=senen_seg[hour/10]; break;
case 1: if(count_time>=2000) P1&=senen_seg[hour/10]; break;
case 2: if(delayed_hour==24) P1=0xfe; else P1&=senen_seg[delayed_hour/10];
break;
case 3: if(count_bit>=5)P1&=senen_seg[count_hour/10]; else P1=0xff;
break;
case 4: P1&=senen_seg[count_hour/10];
break;
case 5: P1&=senen_seg[count_hour/10]; break;
}
P3_4=0;
delay(10);
if(P3_5==1 && key1_enter==1){
if(count>=127) x=1; else x=2; key1_enter=0;
count=0;
}
if(P3_2==1 && key3_enter==1){
x=4;
key3_enter=0;
}
P3_4=1;
P1|=0xff;
if(program<=1 && count_time>=2000) P1&=0xff;
if(program<=1 && count_time<=2000) P1&=0x7f;
if(program==2) P1&=0x7f;
if(program==3) P1&=0xff;
if(program==4) P1&=0x7f;
if(program==5) P1&=0xff;
y=x;
x=0;
return y;
}
void main(){
P1=0xff;
P3=0xff;
time0_init();
while(1){
switch(program){
case 0: while(program==0){
switch(show_key()){
case 0: break;
case 1: program=0;
break;
case 2: program=1;
break;
}
}
break;
case 1: while(program==1){
switch(show_key()){
case 0: break;
case 1: program=0;
break;
case 2: program=2;
break;
case 3: hour++;
if(hour>=24)hour=0;
break;
case 4: minute++;
if(minute>=60)minute=0;
break;
}
}
break;
case 2: while(program==2){
switch(show_key()){
case 0: break;
case 1: program=0;
break;
case 2: program=3;
break;
case 3: delayed_hour++;
if(delayed_hour>=25)delayed_hour=0;
break;
case 4: delayed_minute++;
if(delayed_minute>=60)delayed_minute=0;
break;
}
}
break;
case 3: while(program==3){
switch(show_key()){
case 0: break;
case 1: program=0;
break;
case 2: program=4;
break;
case 3: count_bit++;
if(count_bit>=7)count_bit=0;
break;
case 4: switch(count_bit){
case 0: count_second+=1;
break;
case 1: count_second+=10;
break;
case 2: count_minute+=1;
break;
case 3: count_minute+=10;
break;
case 4: count_hour+=1;
break;
case 5: count_hour+=10;
break;
case 6: break;
}
if(count_hour>=100) count_hour-=100;
if(count_minute>=60) count_minute-=60;
if(count_second>=60) count_second-=60;
break;
}
if(count_bit==6) countdown_mark=1;
else countdown_mark=0;
}
break;
case 4: count_hour=0;
count_minute=0;
count_second=0;
while(program==4){
switch(show_key()){
case 0: break;
case 1: program=0;
break;
case 2: program=5;
break;
case 3: stopwatch_mark=~stopwatch_mark;
break;
case 4: if(stopwatch_mark==0){
count_hour=0;
count_minute=0;
count_second=0;
}
break;
}
}
break;
case 5: count_hour=0;
count_minute=0;
count_second=0;
while(program==5){
switch(show_key()){
case 0: break;
case 1: program=0;
break;
case 2: program=0;
break;
case 3: count_second++;
if(count_second>=100){
count_second=0;
count_minute++;
if(count_minute>=100){
count_minute=0;
count_hour++;
if(count_hour>=100)count_hour=0;
}
}
break;
case 4: count_hour=0;
count_minute=0;
count_second=0;
break;
}
if(P3_7==0){
while(P3_7==0) show_key();
count_second++;
if(count_second>=100){
count_second=0;
count_minute++;
if(count_minute>=100){
count_minute=0;
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