Diff: main.cpp

Revision:

0:f2b51b7dab8f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Oct 15 21:23:00 2012 +0000
@@ -0,0 +1,56 @@
+/* Program Example 6.3: Host keypress to 7-seg display
+                                                              */
+#include "mbed.h"
+Serial pc(USBTX, USBRX);                         // comms to host PC
+BusOut Seg1(p5,p6,p7,p8,p9,p10,p11,p12);         // A,B,C,D,E,F,G,DP
+BusOut Seg2(p13,p14,p15,p16,p17,p18,p19,p20);    // A,B,C,D,E,F,G,DP
+
+void SegInit(void);                          // function prototype
+void HostInit(void);                         // function prototype
+char GetKeyInput(void);                      // function prototype
+char SegConvert(char SegValue);              // function prototype
+char data1, data2;                           // variable declarations
+
+int main() {         // main program
+  SegInit();         // call function to initialise the 7-seg displays 
+  HostInit();        // call function to initialise the host terminal              
+  while (1) {                 // infinite loop
+    data2 = GetKeyInput();    // call function to get 1st key press
+    Seg2=SegConvert(data2);   // call function to convert and output
+    data1 = GetKeyInput();    // call function to get 2nd key press
+    Seg1=SegConvert(data1);   // call function to convert and output
+    pc.printf("  ");          // display spaces between numbers
+  }
+}
+// functions
+void SegInit(void) {
+  Seg1=SegConvert(0);        // initialise to zero
+  Seg2=SegConvert(0);        // initialise to zero
+}
+
+void HostInit(void) {
+  pc.printf("\n\rType two digit numbers to be displayed\n\r");
+}
+
+char GetKeyInput(void) {
+  char c = pc.getc();      // get keyboard data (ascii 0x30-0x39)
+  pc.printf("%c",c);       // print ascii value to host PC terminal
+  return (c&0x0F);         // apply bit mask to convert to decimal, and return 
+}
+
+char SegConvert(char SegValue) {        // function 'SegConvert'
+  char SegByte=0x00;
+  switch (SegValue) {                   //DP G F E D C B A
+    case 0 : SegByte = 0x3F;break;      // 0 0 1 1 1 1 1 1 binary
+    case 1 : SegByte = 0x06;break;      // 0 0 0 0 0 1 1 0 binary
+    case 2 : SegByte = 0x5B;break;      // 0 1 0 1 1 0 1 1 binary
+    case 3 : SegByte = 0x4F;break;      // 0 1 0 0 1 1 1 1 binary
+    case 4 : SegByte = 0x66;break;      // 0 1 1 0 0 1 1 0 binary
+    case 5 : SegByte = 0x6D;break;      // 0 1 1 0 1 1 0 1 binary
+    case 6 : SegByte = 0x7D;break;      // 0 1 1 1 1 1 0 1 binary
+    case 7 : SegByte = 0x07;break;      // 0 0 0 0 0 1 1 1 binary
+    case 8 : SegByte = 0x7F;break;      // 0 1 1 1 1 1 1 1 binary
+    case 9 : SegByte = 0x6F;break;      // 0 1 1 0 1 1 1 1 binary
+  }
+    return SegByte;
+}
\ No newline at end of file