FRDM-K64F Code Share
The chronometer works receiving orders from a serial port at 9600bps: ASCII 1 for START ASCII 2 for PAUSE ASCII 3 for RESET The display module is a 8550, which has 4 digits, so the chronometer max count is 1 minute. Used Ticker for generating interrupts at 100 Hz frequency
Dependencies: mbed
Fork of
Digital_Chronometer_7_segments_4_digits
by 
Valentin Korenblit
Diff: main.cpp
- Revision:
- 0:73b3e1c6cf2f
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Wed Aug 06 03:04:02 2014 +0000
@@ -0,0 +1,217 @@
+#include "mbed.h"
+#include <string>
+#include <Ticker.h>
+
+
+Ticker cronTimer;
+
+DigitalOut segH(D15);
+DigitalOut segG(D14);
+DigitalOut segF(D13);
+DigitalOut segE(D12);
+DigitalOut segD(D11);
+DigitalOut segC(D10);
+DigitalOut segB(D9);
+DigitalOut segA(D7);
+DigitalOut dig1(D1);
+DigitalOut dig2(D2);
+DigitalOut dig3(D3);
+DigitalOut dig4(D4);
+
+unsigned char flagUART=0;
+unsigned char flagCronTimer=0;
+unsigned char running=0;
+unsigned int centCron=0;
+unsigned int segCron=0;
+unsigned int segCronDec=0;
+unsigned int segCronUni=0;
+unsigned int centCronDec=0;
+unsigned int centCronUni=0;
+int received;
+
+
+Serial pc(USBTX, USBRX);
+
+void writeDigit(int n)
+{
+
+ switch (n) {
+
+
+ case 0:
+ segG=segH=1;
+
+ segA=segB=segC=segD=segE=segF=0; //LEDS ARE ACTIVE-LOW
+ break;
+ case 1:
+ segA=segD=segE=segF=segG=segH=1;
+ segB=segC=0;
+ break;
+ case 2:
+ segC=segF=segH=1;
+ segA=segB=segD=segE=segG=0;
+ break;
+ case 3:
+ segE=segF=segH=1;
+ segA=segB=segC=segD=segG=0;
+ break;
+ case 4:
+ segA=segD=segE=segH=1;
+ segB=segC=segF=segG=0;
+
+ break;
+ case 5:
+ segB=segE=segH=1;
+ segA=segC=segD=segF=segG=0;
+
+ break;
+ case 6:
+ segB=segH=1;
+ segA=segC=segD=segE=segF=segG=0;
+ break;
+ case 7:
+ segD=segE=segF=segG=segH=1;
+ segA=segB=segC=0;
+
+ break;
+ case 8:
+ segH=1;
+ segA=segB=segC=segD=segE=segF=segG=0;
+ break;
+ case 9:
+
+ segD=segE=segH=1;
+ segA=segB=segC=segF=segG=0;
+ break;
+
+ }
+
+}
+
+void updateDisplay(int d1,int d2, int d3, int d4)
+{
+
+
+ dig2=dig3=dig4=1;
+ dig1=0;
+ writeDigit(d1);
+ wait_ms(1.5);
+
+ dig1=dig3=dig4=1;
+ dig2=segH=0;
+ writeDigit(d2);
+ wait_ms(1.5);
+
+ dig1=dig2=dig4=1;
+ dig3=0;
+ writeDigit(d3);
+ wait_ms(1.5);
+
+ dig1=dig2=dig3=1;
+ dig4=0;
+ writeDigit(d4);
+ wait_ms(1.5);
+}
+
+void serialInterruptHandler()
+{
+ string s;
+ s=pc.getc();
+ received= atoi(s.c_str());
+ flagUART=1;
+}
+
+void cronTimerInterruptHandler()
+{
+ flagCronTimer=1;
+}
+
+int main()
+{
+ pc.attach(&serialInterruptHandler);
+
+ while(1) {
+
+ if (flagUART) {
+
+ if(received==1) { //start
+ if(running==0) {
+
+ if((segCron!=59) && (centCron!=99)) {
+ running=1;
+ cronTimer.attach_us(&cronTimerInterruptHandler,10000);//each 10ms
+ pc.printf("RUNNING\n");
+ }
+ }
+ else
+ pc.printf("ALREADY RUNNING\n");
+ flagUART=0;
+ }
+
+ if(received==2) { //pause
+
+ if (running==1) {
+ cronTimer.detach();
+ if(segCron!=59)
+ running=0;
+ pc.printf("PAUSED\n");
+ }
+ else
+ pc.printf("NOT RUNNING\n");
+ flagUART=0;
+
+ }
+
+ if(received==3) { //reset
+ cronTimer.detach();
+ segCron=0;
+ centCron=0;
+ segCronDec=0;
+ segCronUni=0;
+ centCronDec=0;
+ centCronUni=0;
+ running=0;
+ pc.printf("RESET\n");
+ flagUART=0;
+
+ }
+
+
+
+
+ }
+
+
+ if(flagCronTimer) {
+
+ if(running) {
+
+ centCron++;
+
+ if (centCron == 100) {
+ segCron++;
+ centCron=0;
+ }
+
+ if ((segCron==59) & (centCron==99)) { //TURN OFF CHRONOMETER AT 59.99 SECS
+ running=0;
+ cronTimer.detach();
+
+
+ }
+ }
+
+//SPLIT NUMBER INTO DIGITS
+
+ segCronDec=segCron/10;
+ segCronUni=segCron%10;
+ centCronDec=centCron/10;
+ centCronUni=centCron %10;
+
+ //CLEAR FLAG
+ flagCronTimer=0;
+ }
+
+ updateDisplay(segCronDec,segCronUni,centCronDec,centCronUni);
+ }
+}
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