Diff: main.cpp

Revision:

0:af56c309135b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Jun 08 15:17:47 2017 +0000
@@ -0,0 +1,139 @@
+#include "mbed.h"
+#include "MCP23017.h"
+
+const unsigned __int64 FORWARD = 1;
+const unsigned __int64 BACKWARD = 0;
+const unsigned __int64 LIGHTON = 1;
+const unsigned __int64 LIGHTOFF = 0;
+const unsigned __int64 SLOW = 0x4; //0100 = step 5
+const unsigned __int64 NORM = 0x9; //1001 = step 15
+const unsigned __int64 FAST = 0xE; //1110 = step 25
+const unsigned __int64 STOP = 0x1; //0001 = E-STOP
+
+const unsigned __int64 train1 = 0x1; 
+const unsigned __int64 train3 = 0x3;
+const unsigned __int64 def_repeat_count = 5;
+
+int interrupted = 0;
+    
+DigitalOut Track(p20);
+DigitalOut led(LED1);
+InterruptIn int0(p8);
+InterruptIn int1(p9);
+MCP23017 *mcp;
+
+void initialize_mcp() {
+    mcp = new MCP23017(p28, p27, 0x40);  // Connect to mbed int pins 27 and 28,
+                                        // MCP address is 0x40
+    mcp->reset();
+    mcp->writeRegister(0x00, (unsigned char )0xff);
+    mcp->writeRegister(0x01, (unsigned char )0xff);
+    mcp->writeRegister(0x02, (unsigned char )0x00);
+    mcp->writeRegister(0x03, (unsigned char )0x00);
+    mcp->writeRegister(0x04, (unsigned char )0xff);
+    mcp->writeRegister(0x05, (unsigned char )0xff);
+    mcp->writeRegister(0x06, (unsigned char )0xff); 
+    mcp->writeRegister(0x07, (unsigned char )0xff);
+    mcp->writeRegister(0x08, (unsigned char )0xff);
+    mcp->writeRegister(0x09, (unsigned char )0xff);
+    mcp->writeRegister(0x0a, (unsigned char )0x42);
+    mcp->writeRegister(0x0b, (unsigned char )0x42);
+    mcp->writeRegister(0x0c, (unsigned char )0x00);
+    mcp->writeRegister(0x0d, (unsigned char )0x00);
+    
+    wait_ms(100);
+    mcp->readRegister(GPIO);
+}
+
+void DCC_send_command(unsigned int address, unsigned int inst, unsigned int repeat_count){
+    unsigned __int64 command = 0x0000000000000000; // this is a 64-bit integer type, due to the packet size
+    unsigned __int64 temp_command = 0x0000000000000000;
+    unsigned __int64 prefix = 0x3FFF; // 14 1 bits as in the preamble of the data packet
+    unsigned int error = 0x00; // error byte
+    //calculate error detection byte with xor
+    error = address ^ inst;
+    // combine packet bits in basic DCC format
+    command = (prefix<<28)|(address<<19)|(inst<<10)|((error)<<1)|0x01;
+
+    int i = 0;
+
+    // repeat DCC command lots of times
+     while(i < repeat_count) {
+        temp_command = command;
+
+    //loops throught packet bits enconding and sending out digital pulses for a DCC command
+        for (int j=0; j<64; j++) {
+            if((temp_command&0x8000000000000000)==0) { //test packet bit
+
+                Track=0;
+                wait_us(100);
+                Track=1;
+                wait_us(100);
+
+            } else {
+
+                Track=0;
+                wait_us(58);
+                Track=1;
+                wait_us(58);
+
+            }
+
+            temp_command = temp_command<<1;
+        }
+        i++;
+    }
+}
+
+unsigned __int64 create_instruction(){
+    unsigned __int64 instruction = 0x0;
+    unsigned __int64 direction = FORWARD;
+    unsigned __int64 lights = LIGHTON;
+    unsigned __int64 speed = NORM;   
+    
+    return instruction = (0x01<<6)|(direction<<5)|(lights<<4)|speed;
+}
+
+void interrupt_handler(){
+     interrupted = 1;
+}
+
+int main(){
+    initialize_mcp();
+    int0.fall(&interrupt_handler);
+    int1.fall(&interrupt_handler);
+    unsigned __int64 instruction = 0x0;  
+     
+    while(1){    
+        if(interrupted){
+            printf("interrupted\n");
+            mcp->readRegister(INTCAP);
+            int data = mcp->readRegister(GPIO); // value of GPIO is 0x12 
+            //modify instructions
+            printf("%d", data);
+            led = 1; 
+            interrupted = 0; 
+        } else {
+            led = 0;
+        }
+        instruction = (0x01<<6)|(FORWARD<<5)|(LIGHTON<<4)|NORM;
+        DCC_send_command(train3, instruction, def_repeat_count);
+    }
+}
+
+/*
+Interrupts
+INT0 - pin 8
+
+clock en data pins for I2C communication - data sync - hier lezen na een interrupt
+SDA - pin 9
+SCL - pin 10
+
+Sending command signals to train tracks
+DAT - pin 20
+EN - VOUT
+
+
+        instruction = (0x01<<6)|(FORWARD<<5)|(LIGHTON<<4)|STOP;
+        DCC_send_command(train3, instruction, def_repeat_count);
+*/