Andrew Bell
7 seg counter with 3 modes controlled by push button
Diff: main.cpp
- Revision:
- 0:7d75e4df9577
diff -r 000000000000 -r 7d75e4df9577 main.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Wed Mar 03 16:24:55 2021 +0000
@@ -0,0 +1,403 @@
+#include "mbed.h"
+
+// Global variables
+
+int mode; // mode=1 on startup
+ // mode=2 for keypad
+ // mode=3 for serial
+
+//Assign 8 pins digital bus object LED_Disp
+BusOut LED_Disp(p7,p11,p9,p8,p5,p6,p10,p12);
+
+// Pin assignment for 4x3 or 12 key Hex keypad
+// Looking at keyboard front, the left most pin is pin1
+// keypad pin numbers
+// pin 1 = not connected
+// pin 2 = col 2
+// pin 3 = row 1
+// pin 4 = col 1
+// pin 5 = row 4
+// pin 6 = col 3
+// pin 7 = row 3
+// pin 8 = row 2
+// pin 9 = not connected
+//
+
+Serial pc(USBTX, USBRX); // Create serial comms object
+
+// mbed pin assignment for keypad
+DigitalIn row1(p27);
+DigitalIn row2(p22);
+DigitalIn row3(p23);
+DigitalIn row4(p25);
+DigitalOut col1(p26);
+DigitalOut col2(p28);
+DigitalOut col3(p24);
+
+DigitalOut debug_led (LED1); // Debug LED for flashing
+
+Serial s_port(USBTX, USBRX);
+
+
+// Interrupts
+InterruptIn cal_button(p14); // Assign interrupt input object to pin 14
+
+// Prototypes for ISRs
+void cal_isr(void); // Declare ISR for cal button on p14
+
+// Function Prototypes
+char Keypad(void); // Declare Keypad function will return character pressed
+void DisplayChar(char); // Declare function to display character on 7 segment
+void Flash_char(char); // Declare function to flash character on 7 segment
+
+
+
+
+
+// ************ MAIN ************
+int main()
+{
+ mode=1; // On startup set mode=1
+
+ cal_button.rise(&cal_isr); //Attach address of ISR to interrupt
+
+ int counter=0; // General program or character counter
+
+ int kp_char = ' '; // Character read from keypad (ASCII)
+
+
+ while(1)
+ {
+ if(mode==1) // Check if startup mode is set
+ {
+ if(counter>=5)
+ counter=0; // Reset counter
+
+ if (counter==0)
+ Flash_char('H'); // Flash 'H'
+ else if (counter==1)
+ Flash_char('E'); // Flash 'E'
+ else if (counter==2)
+ Flash_char('L'); // Flash 'L'
+ else if (counter==3)
+ Flash_char('L'); // Flash 'L'
+ else if (counter==4)
+ Flash_char('0'); // Flash '0'
+
+
+ counter++; //Increment message counter
+ }
+
+
+
+ else if(mode==2) // Check if keypad mode
+ {
+
+ counter=0; // reset message counter
+
+ kp_char = Keypad(); // Poll keypad and check if key pressed
+
+ if(kp_char!=' ') // If keypad char == ' ' then no key pressed
+ {
+
+ if(kp_char>='0' && kp_char<='9')
+ {
+ DisplayChar(kp_char); // Display character on 7 segment
+ pc.printf("%c\n\r",kp_char); // Send character to serial port
+
+ }
+ }
+ }
+
+
+ else if(mode==3) // Check if serial mode
+ {
+ kp_char = Keypad(); // Poll keypad and check if key pressed
+
+ if(s_port.readable())
+ {
+
+ kp_char = s_port.getc(); // Display character on 7 segment
+
+
+ if(kp_char>='0' && kp_char<='9')
+ {
+ DisplayChar(kp_char); // Display character on 7 segment
+ pc.printf("%c\n\r",kp_char); // Send character to serial port
+
+ }
+
+ }
+ }
+ }
+}
+
+
+// ISR function called by interrupt on push button
+void cal_isr(void)
+{
+ // Switch modes
+ if(mode==1)
+ {
+ mode=2; // Set mode to keypad mode
+ DisplayChar(' '); // Turn off all segments
+ //wait(0.1); //Debounce timer
+ }
+ else if(mode==2)
+ {
+ mode=3; // Set mode to serial mode
+ DisplayChar(' '); // Turn off all segments
+ //wait(0.1); //Debounce timer
+ }
+ else if(mode==3)
+ {
+ mode=1; // Set mode to startup mode
+ DisplayChar(' '); // Turn off all segments
+ //wait(0.1); //Debounce timer
+ }
+}
+
+
+// Function to flash character on 7 segment
+void Flash_char(char new_char)
+{
+ DisplayChar(' '); // Turn off all segments
+ wait(0.1);
+ DisplayChar(new_char); // Display chararacter on 7 segment
+ wait(0.6);
+}
+
+
+
+
+char Keypad(void)
+{
+
+ // Test for any key pressed on column 1
+ // Pull col1 high and keep columns 2 and 3 low
+ col1=1;
+ col2=0;
+ col3=0;
+
+
+ if(row1==1) // While col1 is high, if row 1 is high then '1' is pressed
+ {
+ while(row1==1){} // Loop while button is pressed down
+ // On releasing the button return the button character and exit function
+
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('1'); // return character 1 and exit function
+ }
+ else if(row2==1) // While col1 is high, if row 2 is high then '4' is pressed
+ {
+ while(row2==1){}
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('4'); // Exit function and return
+ }
+ else if(row3==1) // While col1 is high, if row 3 is high then '7' is pressed
+ {
+ while(row3==1){}
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('7');
+ }
+ else if(row4==1) // While col1 is high, if row 4 is high then '*' is pressed
+ {
+ while(row4==1){}
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('*');
+ }
+
+
+
+ // Test for any key pressed on column 2
+ // Pull col2 high and keep columns 1 and 3 low
+ col1=0;
+ col2=1;
+ col3=0;
+
+ if(row1==1) // While col2 is high, if row 1 is high then '2' is pressed
+ {
+ while(row1==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('2');
+ }
+ else if(row2==1) // While col2 is high, if row 2 is high then '5' is pressed
+ {
+ while(row2==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('5');
+ }
+ else if(row3==1) // While col2 is high, if row 3 is high then '8' is pressed
+ {
+ while(row3==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('8');
+ }
+ else if(row4==1) // While col2 is high, if row 4 is high then '0' is pressed
+ {
+ while(row4==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('0');
+ }
+
+
+ // Test for any key pressed on column 3
+ // Pull col3 high and keep columns 1 and 2 low
+ col1=0;
+ col2=0;
+ col3=1;
+
+ if(row1==1) // While col3 is high, if row 1 is high then '3' is pressed
+ {
+ while(row1==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('3');
+ }
+ else if(row2==1) // While col3 is high, if row 2 is high then '6' is pressed
+ {
+ while(row2==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('6');
+ }
+ else if(row3==1) // While col3 is high, if row 3 is high then '9' is pressed
+ {
+ while(row3==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('9');
+ }
+ else if(row4==1) // While col3 is high, if row 4 is high then '#' is pressed
+ {
+ while(row4==1){} // Loop
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+ return('#');
+ }
+
+ // Pull all colums low to end
+ col1=0;
+ col2=0;
+ col3=0;
+
+
+ // ***** Return value ******
+ return(' '); // If no key is pressed then return ' ' a space character.
+
+} // Keypad Function End
+
+
+
+
+// Function to display a character on 7 segment LED display
+void DisplayChar(char disp_char)
+{
+ switch(disp_char)
+ {
+ case '0':
+ LED_Disp = ~0x3F; // Bit pattern for '0' = ~0xC0
+ break;
+ case '1':
+ LED_Disp = ~0x06; // Bit pattern for '1' = ~0xF9
+ break;
+ case '2':
+ LED_Disp = ~0x5B; // Bit pattern for '2' = ~0xA4
+ break;
+ case '3':
+ LED_Disp = ~0x4F; // Bit pattern for '3' = ~0xB0
+ break;
+ case '4':
+ LED_Disp = ~0x66; // Bit pattern for '4' = ~0x99
+ break;
+ case '5':
+ LED_Disp = ~0x6D; // Bit pattern for '5' = ~0x92
+ break;
+ case '6':
+ LED_Disp = ~0x7D; // Bit pattern for '6' = ~0x82
+ break;
+ case '7':
+ LED_Disp = ~0x07; // Bit pattern for '7' = ~0xF8
+ break;
+ case '8':
+ LED_Disp = ~0x7F; // Bit pattern for '8' = ~0x80
+ break;
+ case '9':
+ LED_Disp = ~0x67; // Bit pattern for '9' = ~0x98
+ break;
+ case 'A':
+ LED_Disp = ~0x77; // Bit pattern for 'A' = ~0x77
+ break;
+ case 'B':
+ LED_Disp = ~0x7F; // Bit pattern for 'B' = ~0x7F
+ break;
+ case 'C':
+ LED_Disp = ~0x39; // Bit pattern for 'C' = ~0x39
+ break;
+ case 'D':
+ LED_Disp = ~0x3F; // Bit pattern for 'D' = ~0x3F
+ break;
+ case 'E':
+ LED_Disp = ~0x79; // Bit pattern for 'E' = ~0x79
+ break;
+ case 'F':
+ LED_Disp = ~0x71; // Bit pattern for 'F' = ~0x71
+ break;
+ case 'G':
+ LED_Disp = ~0x7D; // Bit pattern for 'G' = ~0x7D
+ break;
+ case 'H': // Display character 'H' = ~0x77
+ LED_Disp = ~0x76;
+ break;
+ case 'I': // Display character 'I' = ~0x06
+ LED_Disp = ~0x06;
+ break;
+ case 'L': // Display character 'L' = ~0x38
+ LED_Disp = ~0x38;
+ break;
+ case 'S':
+ LED_Disp = ~0x6D; // Bit pattern for 'S' = ~0x92
+ break;
+ case ' ': // Display character ' ' = ~0x00
+ LED_Disp = ~0x00;
+ break;
+ case '*': // keypad '*' character
+ LED_Disp = ~0x63; // Top 4 segments
+ break;
+ case '#': // keypad '#' character
+ LED_Disp = ~0x5C; // Bottom 4 segments
+ break;
+ }
+}