Diff: main.cpp

Revision:

0:544b5f6ad832

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Dec 01 04:39:00 2010 +0000
@@ -0,0 +1,203 @@
+#include "mbed.h"
+#include "pt.h"
+
+#define numsamples 1
+#define sizeofpattern 30    // max size of string length
+
+
+//  function declartion
+int touchSense(int Num_Charger);
+void displayString(int* String);
+void displayMessage(int NumMes);
+
+//  I/O declarations
+DigitalOut myled(LED1);
+AnalogIn input1(p20), input0(p17);
+DigitalIn charger1(p19), charger0(p16);
+DigitalOut ground(p18);
+Serial pc(USBTX, USBRX); // tx, rx
+
+
+//  variable definitions
+int hostString[sizeofpattern];
+//int currentState = S_idle;
+//int nextState = S_idle;
+
+int i, j, token;
+int NewTokenFlag, StateFlag;   //  NewTokenFlag is 1 when a token is received, otherwise 0
+//  StateFlag is 1 when a state transition decision is made, it is sets to 2 when the system should be reset
+
+//  threads declarations
+static struct pt pt_1, pt_2;
+
+
+//  FSM_transition executes FSM transition
+static int FSM_transition(struct pt *pt) {
+
+    PT_BEGIN(pt);
+
+    StateFlag = 1;  // let IO_handler run first
+
+    while (1) {
+        PT_WAIT_UNTIL(pt, (NewTokenFlag==1));
+        if (token == 'S') {
+            NewTokenFlag = 0;
+            break;
+        } else { // handle the case when the input is not S
+            displayMessage(1);
+            NewTokenFlag = 0;
+            StateFlag = 1;
+        }
+    }
+
+    //
+    //printf("S_HostInput \n");
+    //
+
+    //  currentState = S_HostInput
+    i = 0;
+    while (1) {
+        StateFlag = 1;
+        PT_WAIT_UNTIL(pt, NewTokenFlag);
+        NewTokenFlag = 0;
+        if (token=='E')  break;
+        else if ((token=='0'||token=='1')&& i<sizeofpattern) {
+            hostString[i] = token;
+            i++;
+        }
+
+        else {
+            displayMessage(1);  // currentState = S_HostError
+            i = 0;
+            StateFlag =2;   //  indicate the system should be reset
+            break;
+        }
+    }
+
+    if (StateFlag!=2) {     // skip S_UserInput if the sysetem should be reset
+        //    currentState = S_UserInput
+        //
+        //printf("S_UserInput ------- \n");
+        //
+        j =0;
+        while (1) {
+            StateFlag = 1;
+            PT_WAIT_UNTIL(pt, NewTokenFlag);
+            NewTokenFlag = 0;
+
+            if (hostString[j]==token) {
+                j++;
+                if (j==i) {
+                    displayMessage(2);  //  currentState = S_Match
+                    break;
+                }
+            } else {
+                displayMessage(0);  //  currentState = S_UserError
+                j = 0;
+                continue;           //   returns S_UserInput
+            }
+
+            StateFlag = 2;  //  indicates the system should be reset
+        }   //  end of while
+    }   // end of skip
+
+    PT_END(pt);
+}
+
+
+//  IO_handler polls the I/O ports
+static int IO_Handler(struct pt *pt) {
+    PT_BEGIN(pt);
+    while (1) {
+        if (StateFlag == 2) break;  //  reacts when the system is rest
+
+        PT_WAIT_UNTIL(pt, StateFlag==1);
+        //
+        //printf("CP 2 ------- \n");
+        //
+        if (pc.readable()) {
+            token = pc.getc();
+            pc.putc(token);
+            NewTokenFlag = 1;
+            StateFlag = 0;
+        } else if (touchSense(0)) {
+            myled=1;
+            token = '0';
+            pc.putc('0');
+            NewTokenFlag = 1;
+            StateFlag = 0;
+        } else if (touchSense(1)) {
+            myled=1;
+            token = '1';
+            pc.putc('1');
+            NewTokenFlag = 1;
+            StateFlag = 0;
+        } else myled =0;
+        wait(0.1);
+        //
+        //printf("CP 3 ------- \n");
+        //
+    }
+
+    PT_END(pt);
+}
+
+
+
+int main() {
+    PT_INIT(&pt_1);
+    PT_INIT(&pt_2);
+    StateFlag =0;
+    NewTokenFlag =0;
+
+    while (1) {
+
+        FSM_transition(&pt_1);
+        IO_Handler(&pt_2);
+    }
+    return 0;
+}   //  end of main
+
+
+int touchSense(int Num_Charger) {
+    float sample1, sample2;
+    ground = 0;
+    if (Num_Charger ==1) {
+        charger1.mode(PullUp);
+        charger1.mode(PullNone);
+        sample1=input1.read();  // take two samples to avoid the random jump on voltage on touch sensor
+        wait(0.1);
+        sample2=input1.read();
+    } else {
+        charger0.mode(PullUp);
+        charger0.mode(PullNone);
+        sample1=input0.read();  // take two samples to ignore temp jump
+        wait(0.1);
+        sample2=input0.read();
+    }
+
+    if (sample1 < 0.3 && sample2 < 0.3) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+
+
+void displayString(int* String) {
+    for (int j=0; j<sizeofpattern; j++)
+        pc.putc(String[j]);
+
+    pc.putc('\n');
+
+}
+
+void displayMessage(int NumMes) {
+    if (NumMes == 1)
+        printf("HOST ERROR : Host must send string in the form of Sxxxx...E X=0 or 1 \n");
+    else if (NumMes == 0)  printf("TOUCH ERROR: Please enter the string that matched host string exactly through touchsensor\n");
+    else   printf("MATCH: Host will send another string\n");
+
+}
+