Diff: main.cpp

Revision:

10:f26deacef98d

Parent:

9:c907be24e49e

--- a/main.cpp	Wed May 06 05:24:41 2015 +0000
+++ b/main.cpp	Fri May 08 14:31:44 2015 +0000
@@ -1,158 +1,138 @@
 #include "mbed.h"
 #include "stdio.h"
+#include "math.h"
 #include "C12832.h"
 
+//To Do:
+//Fix crc_passed logic
+
+//Improvements:
+//Increase bandwidth by reducing wasted nibbles from CRC
+
+//Changes:
+//unsigned chars moved
+//removed nibble
+//added CRC
+
+//multicast using 4bit address / 4 bit network. network = 4 msb, address = 4 lsb. broadcast = all 0's. multicast = network id & address of 0's.
 #define MAX 100 //set the size of the character data storage array
 #define BYTE 8
-#define NIBBLE 4 //used to set size of data read
 #define PREAMBLE 0x7E //preamble of 01111110
 #define POSTAMBLE 0x81 //postamble of 10000001
 #define ADDRESS 0x11 //address of 00010010 - network of 1, id of 2.
-#define NETWORK 0x10 //network portion of the address
-#define ID 0x02 //id portion of the address
 #define BROADCAST 0x00 //address of 00000000
-//multicast using 4bit address / 4 bit network. network = 4 msb, address = 4 lsb. broadcast = all 0's. multicast = network id & address of 0's.
 #define CRC 0x13 //crc of 10011 or x^4+x+1 or crc-5
 
-
+Timer t; //timer for pausing after data RXed before displaying data
+DigitalOut myled(LED1); // red led on board
 C12832 lcd(p5, p7, p6, p8, p11); //LCD structure
-DigitalOut myled(LED1), myled2(LED2), myled3(LED3), myled4(LED4); //variables to access the four blue leds
-DigitalIn clock_pin(p21), serial_in(p22); //clock pulse input and data input pins
-Timer t; //timer for pausing after postamble received before displaying data
-unsigned char temp, data[MAX], crc_calc=0; //temp byte storage, storage array, transmitted crc value
-char c[1];//temp_data moved from unsigned char
+int msecs, sksecs; //clock time needed for data transfer and skew time
+DigitalIn clock_pin(p21); //clock pulse input and data input pins
+DigitalInOut serial_in(p22);//Recieve, send for ACK
+
+unsigned char temp, crc_calc; //temp byte storage, storage array, transmitted crc value
+char c[1];//Used for troubleshooting to send a char to LCD
+char data[MAX];//data array
 unsigned char preamble, address, i, j, k, temp_data,FCS; //increment variables
-unsigned char data_flag, rflag, d_flag, done; //data flags
-int crc_passed = 0; //crc flag
-int temp_crc = 0; //stores values for crc check.
+unsigned char data_flag, rflag, done_flag1, done_flag2; //data flags
+int crc_passed = 0, temp_crc = 0; //CRC Flag, stores values for crc check.
 
 //funtion prototypes
-void check_byte(int value); //stays inside the function until the received byte matches the value passed into the function (PREAMBLE)
-int check_abyte();//after preamble received checks the next byte for address. Returns 1 if address received matches ADDRESS, BROADCAST, or multicast; 0 if not.
-int read_byte(int size); //reads received data and returns it a byte at a time.
-int get_crc(int temp_crc);
-
-//Improvements
-//if crc correct display correct crc
-//if crc correct send ACK(1) to Master
-//if crc wrong, display incorrect crc
-//if crc wrong, send NoACK(0) to Master
-//if crc wrong adjust for retransmit
-
+void check_byte(int value); //stays inside the function until the RXed byte matches the value passed into the function (PREAMBLE)
+int check_abyte();//after preamble RXed checks the next byte for address. Returns 1 if address RXed matches ADDRESS, BROADCAST, or multicast; 0 if not.
+int read_byte(int size); //reads RXed data and returns it a byte at a time.
+int get_crc(int temp_crc);//Get CRC value on data temp_crc
+void Ms_Delay(int msec);
+void lcdClear(void);
+void print(char str[]);
+void send_ACK(int ACK);
 
 int main()
 {
-
-    //turn off leds
-    myled = 1;
-
-    //initialize variables
-    i = 0;
-    d_flag = 0;
-    done = 0;
-    crc_passed=0;
+    clock_pin.mode(PullUp);//Enable PullUp Resistors
+    serial_in.mode(PullUp);//Enable PullUp Resistors
+    myled=0;//Turn LED On
     //clear lcd screen, print current build message
-    lcd.cls();
-    lcd.locate(0,3);
-    lcd.printf("Serial Communication Device Started");
-
-    while(!d_flag) {
-        //read input clock pulse and data checking for preamble.
-        //preamble while loop
-        check_byte(PREAMBLE);
-
-        //clear lcd screen, print current build message
-        lcd.cls();
-        lcd.locate(0,3);
-        lcd.printf("Preamble Received");
-
-        //preamble received check address (next byte), returns to preamble check if not addressed to station
-        if(check_abyte())
-            d_flag = 1;
-        else {
-            //pause after incorrect address - so message is visible, then display waiting for preamble
-            t.start();
-            //wait until the timer has reached the set time.
-            while(t.read_ms() < 500) {
-
-            }
-            //stop and reset the timer
-            t.stop();
-            t.reset();
-            //clear lcd screen, print current build message
-            lcd.cls();
-            lcd.locate(0,3);
-            lcd.printf("Waiting for preamble");
-        }
-    }
+    lcdClear();
+    print("Comm Started");
+    Ms_Delay(500);//Wait 500mS
+    while(true) {
+        //initialize variables
+        i = 0;
+        done_flag1 = 0;
+        done_flag2 = 0;
+        crc_passed=0;
 
-    while(!done) {
-        //store data into character array if crc checks.
-        temp_data = read_byte(BYTE); //store successfully transmitted data
+        while(!done_flag1) {
+            //read input clock pulse and data checking for preamble.
+            //preamble while loop
+            check_byte(PREAMBLE);
+            myled=0;//Turn LED On
+            //clear lcd screen, print current build message
+            lcdClear();
+            print("Pre RXed");
 
-        //check for postamble
-        if(temp_data == POSTAMBLE) {
-            //break out of while loop - data finished sending
-            done = 1;
-            //clear lcd screen, print postamble message
-            lcd.cls();
-            lcd.locate(0,3);
-            lcd.printf("Postamble Received");
-        }
-        //store data in character array if not postamble - check crc when appropriate
-        else {//recieves hh instead of h 0x06
-            //byte1, crc1, byte2, crc2
-            data[i]=0;
-            data[i] = temp_data;
-            temp_crc=temp_data<<4;
-            //////////////////////////////////////////////////////////doesnt seem to be reading in fast enough
-            FCS = read_byte(BYTE); //store successfully transmitted data
-            c[0]=(FCS & 0x0F)+0x30;
-            lcd.cls();
-            lcd.locate(0,3);
-            lcd.printf(c);
-//            t.start();
-////wait until the timer has reached the set time.
-//            while(t.read_ms() < 1000) {
-//            }
-////stop and reset the timer
-//            t.stop();
-//            t.reset();
-            temp_crc=temp_crc+(FCS & 0x0F);//grab the last 4 bits from crc value byte
-            if(get_crc(temp_crc)==0) {
-                crc_passed=1;
-                lcd.cls();
-                lcd.locate(0,3);
-                lcd.printf("Data passes CRC verification.");
-            } else {
-                crc_passed=crc_passed & 0;
-                lcd.cls();
-                lcd.locate(0,3);
-                lcd.printf("Data fails CRC verification, Int Data: %x, CRC Byte %x.", temp_crc, crc_calc);
+            //preamble RXed check address (next byte), returns to preamble check if not addressed to station
+            if(check_abyte())
+                done_flag1 = 1;
+            else {
+                //clear lcd screen, print current build message
+                lcdClear();
+                print("Wait for pre");
             }
         }
-        i++; //increment array position
-        //zero out crc temp variables
-        temp_crc = 0;
-    }
-//pause after displaying postamble received and then display data.
-    t.start();
-//wait until the timer has reached the set time.
-    while(t.read_ms() < 1000) {
+
+        while(!done_flag2) {
+            //store data into character array if crc checks.
+            temp_data = read_byte(BYTE); //store successfully transmitted data
+
+            //check for postamble
+            if(temp_data == POSTAMBLE) {
+                //break out of while loop - data finished sending
+                done_flag2 = 1;
+                //clear lcd screen, print current build message
+                lcdClear();
+                print("Post RXed");
+            }
 
+            //store data in character array if not postamble - check crc when appropriate
+            else {
+                //byte1, crc1, byte2, crc2
+                data[i]=0;
+                data[i] = temp_data;
+                temp_crc=temp_data<<4;
+                FCS = read_byte(BYTE); //store successfully transmitted data
+                temp_crc=temp_crc+(FCS & 0x0F);//grab the last 4 bits from crc value byte
+                if(get_crc(temp_crc)==0) {
+                    crc_passed=1;
+                    lcdClear();
+                    print("pass CRC");
+                } else {
+                    crc_passed=crc_passed & 0;//needs to be fixed
+                    lcdClear();
+                    print("fail CRC");
+                }
+            }
+            i++; //increment array position
+            temp_crc = 0;//zero out crc temp variables
+        }
+        //pause after displaying postamble RXed and then display data.
+        //Ms_Delay(1000);//Display Postamble Message
+        if(crc_passed) { //if crc passes display data, send ACK
+            //clear debugging messages - and reset lcd to original position before printing data.
+            //send ACK
+            lcdClear();
+            print("RXed: ");
+            print(data);
+            send_ACK(0x1);
+//        for(k=0; k<=i; k++)
+//            print("%c", data[k]);
+        } else { //if crc fails, send NOACK
+            send_ACK(0x0);
+        }
+        myled=1;
+        //Ms_Delay(1000);
     }
-//stop and reset the timer
-    t.stop();
-    t.reset();
-//if(crc_passed){//if crc passes display data, send ACK
-//clear debugging messages - and reset lcd to original position before printing data.
-//send ACK
-    lcd.cls();
-    lcd.locate(0,3);
-    lcd.printf("Received: ");
-    for(k=0; k<=i; k++)
-        lcd.printf("%c", data[k]);
-
 }
 
 void check_byte(int value)
@@ -200,21 +180,25 @@
     }
 
     //clear lcd screen, print current build message
-    lcd.cls();
-    lcd.locate(0,3);
+    lcdClear();
+
     if(temp == ADDRESS) {
         rflag = 1;
-        lcd.printf("Address Received");
+        print("Addrss RXed");
     } else if(temp == BROADCAST) {
         rflag = 1;
-        lcd.printf("Broadcast received");
-    } else if(((temp & 0xF0) == NETWORK) && ((temp & 0x0F) == 0)) {
+        print("Brdcst RXed");
+    } else if(((temp & 0xF0) == (ADDRESS & 0xF0)) && ((temp & 0x0F) == 0)) {
+        rflag = 1;
+        print("Multicst1 RXed");
+    } else if(((temp & 0xF0) == 0) && ((temp & 0x0F) == (ADDRESS & 0x0F))) {
         rflag = 1;
-        lcd.printf("Multicast received");
-    }//can add if Network==0 and address==x send to x in every network
-    else
-        lcd.printf("Wrong address received");
-
+        print("Multicst2 RXed");
+        //can add if Network==0 and address==x send to x in every network
+    } else {
+        print("Wrng addrss RXed");
+    }
+    Ms_Delay(1000);
     return rflag;
 }
 
@@ -231,7 +215,7 @@
             //each new data bit is moved into the least significant bit afater the rest of the bits are shifted to the left
             //data must be sent from the other microcontroller shifted out from the most significant bit to the least significant bit.
             temp = (temp << 1) + serial_in;
-            //increment j (tracks bits received) - turn off data_flag until clock changes.
+            //increment j (tracks bits RXed) - turn off data_flag until clock changes.
             j++;
             data_flag = 0;
         }
@@ -242,6 +226,7 @@
     return temp;
 }
 
+
 int get_crc(int temp_crc)
 {
     int j = 11, b = 0, z = 0, Y = 0, C0 = 0, C1 = 0, C2 = 0, C3 = 0;
@@ -259,4 +244,38 @@
     z=z+C1<<1;
     z=z+C0;
     return z;
+}
+
+void Ms_Delay(int msec)//mS Delay
+{
+    t.start();
+    //wait until the timer has reached the set time.
+    while(t.read_ms() < msec) {
+    }
+    //stop and reset the timer
+    t.stop();
+    t.reset();
+}
+
+void lcdClear() //Clear LCD, for LPC,     lcd.cls();,     lcd.locate(0,3);
+{
+    lcd.cls();
+    lcd.locate(0,3);
+}
+
+void print(char str[])// print String to LCD Display, for LPC,     printf(str);
+{
+    lcd.printf(str);
+}
+
+void send_ACK(int ACK)
+{
+    serial_in = ACK;
+    Ms_Delay(1500);///////////////can reduce time when Arduino Postamble delay is reduced
+//        if(clock_pin) {
+//            //if(!clock_pin && skew_flag && t.read_ms() > sksecs) {//output data before clock high
+//            serial_in = (byte / j) % 2;
+//            j /= 2; //decrement j to get to next bit location
+//        }
+    //reset skew flag
 }
\ No newline at end of file