main.cpp

00001 #include "mbed.h"
00002 
00003 // Global variables
00004 
00005 int mode;  // mode=1 on startup 
00006            // mode=2 for keypad
00007            // mode=3 for serial
00008 
00009 //Assign 8 pins digital bus object LED_Disp
00010 BusOut LED_Disp(p7,p11,p9,p8,p5,p6,p10,p12); 
00011 
00012 // Pin assignment for 4x3 or 12 key Hex keypad
00013 // Looking at keyboard front, the left most pin is pin1 
00014 // keypad pin numbers
00015 //   pin 1 = not connected
00016 //   pin 2 = col 2
00017 //   pin 3 = row 1
00018 //   pin 4 = col 1
00019 //   pin 5 = row 4
00020 //   pin 6 = col 3
00021 //   pin 7 = row 3
00022 //   pin 8 = row 2
00023 //   pin 9 = not connected
00024 //
00025 
00026 Serial pc(USBTX, USBRX); // Create serial comms object
00027 
00028 // mbed pin assignment for keypad
00029 DigitalIn row1(p27);
00030 DigitalIn row2(p22);
00031 DigitalIn row3(p23);
00032 DigitalIn row4(p25);
00033 DigitalOut col1(p26);
00034 DigitalOut col2(p28);
00035 DigitalOut col3(p24);
00036 
00037 DigitalOut debug_led (LED1);  // Debug LED for flashing
00038 
00039 Serial s_port(USBTX, USBRX);
00040 
00041 
00042 // Interrupts
00043 InterruptIn cal_button(p14); // Assign interrupt input object to pin 14
00044 
00045 // Prototypes for ISRs
00046 void cal_isr(void);  // Declare ISR for cal button on p14
00047  
00048 // Function Prototypes
00049 char Keypad(void); // Declare Keypad function will return character pressed
00050 void DisplayChar(char);  // Declare function to display character on 7 segment
00051 void Flash_char(char);  // Declare function to flash character on 7 segment 
00052 
00053 
00054 
00055 
00056 
00057 // ************ MAIN ************
00058 int main() 
00059 {
00060     mode=1;  // On startup set mode=1
00061     
00062     cal_button.rise(&cal_isr); //Attach address of ISR to interrupt
00063     
00064     int counter=0;  // General program or character counter
00065         
00066     int kp_char = ' ';   // Character read from keypad (ASCII)
00067     
00068     
00069     while(1) 
00070     {
00071         if(mode==1)  // Check if startup mode is set
00072         {
00073             if(counter>=5)  
00074                 counter=0;  // Reset counter
00075             
00076             if (counter==0) 
00077                 Flash_char('H'); // Flash 'H' 
00078             else if (counter==1) 
00079                 Flash_char('E'); // Flash 'E'
00080             else if (counter==2) 
00081                 Flash_char('L'); // Flash 'L'
00082             else if (counter==3) 
00083                 Flash_char('L'); // Flash 'L' 
00084             else if (counter==4) 
00085                 Flash_char('0'); // Flash '0'
00086 
00087             
00088             counter++;  //Increment message counter
00089         }
00090         
00091         
00092        
00093         else if(mode==2)  // Check if keypad mode
00094         {
00095             
00096             counter=0;  // reset message counter
00097             
00098             kp_char = Keypad(); // Poll keypad and check if key pressed
00099             
00100             if(kp_char!=' ')  // If keypad char == ' ' then no key pressed
00101             {
00102                 
00103                 if(kp_char>='0' && kp_char<='9')
00104                 {
00105                     DisplayChar(kp_char);  // Display character on 7 segment
00106                     pc.printf("%c\n\r",kp_char);   // Send character to serial port
00107 
00108                 }
00109             }
00110          }   
00111                 
00112                 
00113         else if(mode==3)  // Check if serial mode
00114         {            
00115             kp_char = Keypad(); // Poll keypad and check if key pressed
00116             
00117             if(s_port.readable())
00118             {
00119 
00120                 kp_char = s_port.getc();  // Display character on 7 segment
00121                 
00122  
00123                 if(kp_char>='0' && kp_char<='9')
00124                 {
00125                     DisplayChar(kp_char);  // Display character on 7 segment
00126                     pc.printf("%c\n\r",kp_char);   // Send character to serial port
00127 
00128                 }               
00129                                                
00130             }
00131         }
00132     }
00133 }
00134 
00135 
00136 // ISR function called by interrupt on push button
00137 void cal_isr(void)
00138 {
00139     // Switch modes
00140     if(mode==1)
00141     {
00142         mode=2; // Set mode to keypad mode
00143         DisplayChar(' ');  // Turn off all segments
00144         //wait(0.1);  //Debounce timer
00145     }
00146     else if(mode==2)
00147     {
00148         mode=3;    // Set mode to serial mode
00149         DisplayChar(' ');  // Turn off all segments
00150         //wait(0.1);  //Debounce timer
00151     }
00152     else if(mode==3)
00153     {
00154         mode=1;    // Set mode to startup mode
00155         DisplayChar(' ');  // Turn off all segments
00156         //wait(0.1);  //Debounce timer
00157     }
00158 }
00159 
00160 
00161 // Function to flash character on 7 segment 
00162 void Flash_char(char new_char)  
00163 {
00164     DisplayChar(' ');  // Turn off all segments
00165     wait(0.1);  
00166     DisplayChar(new_char);  // Display chararacter on 7 segment
00167     wait(0.6);   
00168 }
00169     
00170     
00171     
00172 
00173 char Keypad(void)
00174 {   
00175     
00176     // Test for any key pressed on column 1
00177     // Pull col1 high and keep columns 2 and 3 low
00178     col1=1;
00179     col2=0;
00180     col3=0;
00181 
00182     
00183     if(row1==1) // While col1 is high, if row 1 is high then '1' is pressed
00184     {
00185         while(row1==1){}  // Loop while button is pressed down
00186         // On releasing the button return the button character and exit function
00187         
00188         // Pull all colums low to end
00189         col1=0;
00190         col2=0;
00191         col3=0;   
00192         return('1');  // return character 1 and exit function
00193     }
00194     else if(row2==1) // While col1 is high, if row 2 is high then '4' is pressed
00195     {
00196         while(row2==1){}
00197         // Pull all colums low to end
00198         col1=0;
00199         col2=0;
00200         col3=0;   
00201         return('4');  // Exit function and return
00202     }
00203     else if(row3==1) // While col1 is high, if row 3 is high then '7' is pressed
00204     {
00205         while(row3==1){}
00206         // Pull all colums low to end
00207         col1=0;
00208         col2=0;
00209         col3=0;   
00210         return('7');
00211     }
00212     else if(row4==1) // While col1 is high, if row 4 is high then '*' is pressed
00213     {
00214         while(row4==1){}
00215         // Pull all colums low to end
00216         col1=0;
00217         col2=0;
00218         col3=0;   
00219         return('*');
00220     }
00221     
00222     
00223     
00224     // Test for any key pressed on column 2
00225     // Pull col2 high and keep columns 1 and 3 low
00226     col1=0;
00227     col2=1;
00228     col3=0;   
00229     
00230     if(row1==1) // While col2 is high, if row 1 is high then '2' is pressed
00231     {
00232         while(row1==1){}  // Loop 
00233         // Pull all colums low to end
00234         col1=0;
00235         col2=0;
00236         col3=0;   
00237         return('2');
00238     }
00239     else if(row2==1) // While col2 is high, if row 2 is high then '5' is pressed
00240     {
00241         while(row2==1){}  // Loop
00242         // Pull all colums low to end
00243         col1=0;
00244         col2=0;
00245         col3=0;   
00246         return('5');
00247     }
00248     else if(row3==1) // While col2 is high, if row 3 is high then '8' is pressed
00249     {
00250         while(row3==1){}  // Loop
00251         // Pull all colums low to end
00252         col1=0;
00253         col2=0;
00254         col3=0;   
00255         return('8');
00256     }
00257     else if(row4==1) // While col2 is high, if row 4 is high then '0' is pressed
00258     {
00259         while(row4==1){}  // Loop
00260         // Pull all colums low to end
00261         col1=0;
00262         col2=0;
00263         col3=0;   
00264         return('0');
00265     }
00266     
00267     
00268     // Test for any key pressed on column 3
00269     // Pull col3 high and keep columns 1 and 2 low
00270     col1=0;
00271     col2=0;
00272     col3=1;   
00273     
00274     if(row1==1) // While col3 is high, if row 1 is high then '3' is pressed
00275     {
00276         while(row1==1){}  // Loop
00277         // Pull all colums low to end
00278         col1=0;
00279         col2=0;
00280         col3=0;   
00281         return('3');
00282     }
00283     else if(row2==1) // While col3 is high, if row 2 is high then '6' is pressed
00284     {
00285         while(row2==1){}  // Loop
00286         // Pull all colums low to end
00287         col1=0;
00288         col2=0;
00289         col3=0;   
00290         return('6');
00291     }
00292     else if(row3==1) // While col3 is high, if row 3 is high then '9' is pressed
00293     {
00294         while(row3==1){}  // Loop
00295         // Pull all colums low to end
00296         col1=0;
00297         col2=0;
00298         col3=0;   
00299         return('9');
00300     }
00301     else if(row4==1) // While col3 is high, if row 4 is high then '#' is pressed
00302     {
00303         while(row4==1){}  // Loop
00304         // Pull all colums low to end
00305         col1=0;
00306         col2=0;
00307         col3=0;   
00308         return('#');
00309     }
00310     
00311     // Pull all colums low to end
00312     col1=0;
00313     col2=0;
00314     col3=0;   
00315     
00316     
00317     // ***** Return value ******
00318     return(' ');  // If no key is pressed then return ' ' a space character.
00319 
00320 } // Keypad Function End
00321 
00322 
00323 
00324 
00325 // Function to display a character on 7 segment LED display
00326 void DisplayChar(char disp_char)
00327 {
00328     switch(disp_char)
00329     {
00330         case '0':
00331             LED_Disp = ~0x3F; // Bit pattern for '0' = ~0xC0
00332             break;        
00333         case '1':
00334             LED_Disp = ~0x06; // Bit pattern for '1' = ~0xF9
00335             break;
00336         case '2':
00337             LED_Disp = ~0x5B; // Bit pattern for '2' = ~0xA4
00338             break;
00339         case '3':
00340             LED_Disp = ~0x4F; // Bit pattern for '3' = ~0xB0
00341             break;
00342         case '4':
00343             LED_Disp = ~0x66; // Bit pattern for '4' = ~0x99
00344             break;
00345         case '5':
00346             LED_Disp = ~0x6D; // Bit pattern for '5' = ~0x92
00347             break;
00348         case '6':
00349             LED_Disp = ~0x7D; // Bit pattern for '6' = ~0x82
00350             break;
00351         case '7':
00352             LED_Disp = ~0x07; // Bit pattern for '7' = ~0xF8
00353             break;
00354         case '8':
00355             LED_Disp = ~0x7F; // Bit pattern for '8' = ~0x80
00356             break;
00357         case '9':
00358             LED_Disp = ~0x67; // Bit pattern for '9' = ~0x98
00359             break;
00360         case 'A':
00361             LED_Disp = ~0x77; // Bit pattern for 'A' = ~0x77
00362             break;
00363         case 'B':
00364             LED_Disp = ~0x7F; // Bit pattern for 'B' = ~0x7F
00365             break;
00366         case 'C':
00367             LED_Disp = ~0x39; // Bit pattern for 'C' = ~0x39
00368             break;
00369         case 'D':
00370             LED_Disp = ~0x3F; // Bit pattern for 'D' = ~0x3F
00371             break;
00372         case 'E':
00373             LED_Disp = ~0x79; // Bit pattern for 'E' = ~0x79
00374             break;
00375         case 'F':
00376             LED_Disp = ~0x71; // Bit pattern for 'F' = ~0x71
00377             break;
00378         case 'G':
00379             LED_Disp = ~0x7D; // Bit pattern for 'G' = ~0x7D
00380             break;
00381         case 'H':    // Display character 'H' = ~0x77
00382             LED_Disp = ~0x76; 
00383             break;
00384         case 'I':    // Display character 'I' = ~0x06
00385             LED_Disp = ~0x06; 
00386             break;
00387         case 'L':    // Display character 'L' = ~0x38
00388             LED_Disp = ~0x38; 
00389             break;
00390         case 'S':
00391             LED_Disp = ~0x6D; // Bit pattern for 'S' = ~0x92
00392             break;
00393         case ' ':    // Display character ' ' = ~0x00
00394             LED_Disp = ~0x00; 
00395             break;
00396         case '*':     // keypad '*' character
00397             LED_Disp = ~0x63; // Top 4 segments 
00398             break;
00399         case '#':    // keypad '#' character
00400             LED_Disp = ~0x5C; // Bottom 4 segments 
00401             break;
00402    }
00403 }