Diff: main.cpp

Revision:

1:38815edb0ecb

Parent:

0:547c5459faa6

Child:

2:b38d6345dd14

--- a/main.cpp	Sun Sep 25 03:44:08 2011 +0000
+++ b/main.cpp	Sun Sep 25 16:22:03 2011 +0000
@@ -48,7 +48,7 @@
 #include "mbed.h"
 #include "stdint.h"
 #include "usbhid.h"
-
+#include "IOMacros.h"
 
 USBJoystick joystick;
 
@@ -118,13 +118,43 @@
 DigitalInOut inout(p14);            // Connect controller here
 // using 220 ohm pull-up
 Serial pc(USBTX, USBRX);
-
+DigitalOut led(LED1);
 uint8_t x, y;
+volatile char bit_count;
 union controls { /* A definition and a declaration */
     uint8_t array[4];
     uint32_t result_32;
 } controls;
 
+/** EINT3_IRQHandler
+ */
+void ISR(void);
+extern "C" void EINT3_IRQHandler(void) {
+
+    // The "event" is connected to pin p10 which is LPC1768 P0_1
+    // so lets trap that and ignore all other GPIO interrupts.    
+    // Test for IRQ on Port0.
+
+    if (LPC_GPIOINT->IntStatus & 0x1) {
+    // If P0_16/p14 rises, call atint()
+        if (LPC_GPIOINT->IO0IntStatF & (1 << 16))  ISR();
+    }
+    // Clear this and all other possible GPIO generated interrupts as they don't concern us.    
+    LPC_GPIOINT->IO2IntClr = (LPC_GPIOINT->IO2IntStatR | LPC_GPIOINT->IO2IntStatF);
+    LPC_GPIOINT->IO0IntClr = (LPC_GPIOINT->IO0IntStatR | LPC_GPIOINT->IO0IntStatF);
+
+}
+
+void event_irq_init(void) {
+    // Use macro to set p10 as an input.
+    //p10_AS_INPUT; 
+    // Enable P0_16/p14 for falling edge interrupt generation.
+    LPC_GPIOINT->IO0IntEnF |= (1UL << 16);
+    // Enable the interrupt.
+    //NVIC_EnableIRQ(EINT3_IRQn);
+}
+
+
 // Temp array for controller data
 
 /* void delay(unsigned int n) is used as a short delay to
@@ -136,6 +166,13 @@
         ;
 }
 
+void ISR(){
+    delay(48);
+    if (inout.read()) controls.result_32 |= (1UL<< bit_count);
+    else controls.result_32  &= ~(1UL << bit_count);
+    bit_count++;
+}
+
 /* int receive(char *data_array, unsigned char n) is used to
    receive a bit stream of bits into an array of n bytes coming
    from the controller. This must be called immediately after
@@ -143,36 +180,18 @@
  */
 
 int receive(uint8_t *data_array, unsigned char n) {
-    unsigned char sample, previous_sample;
-    unsigned char bit, byte;
+       
     int i;
-
+    bit_count=0;
 
-    //inout.input();                // Not sure about this..
+    NVIC_EnableIRQ(EINT3_IRQn);
 
-    sample = inout.read();
-    for (i=0;i < n ;i++) {
-        byte = 0;
-        bit  = 0;
-        while (bit<8) {
-            previous_sample = sample;
-            sample = inout.read();
-            if ((previous_sample ^ sample) & previous_sample) {
+    while(bit_count<33){
+        ;//Wait for Interrupts
+        }
+       led=1;
+    NVIC_DisableIRQ(EINT3_IRQn);
 
-                delay(60);
-                sample=inout.read();
-                if (sample)
-                    byte = byte  | (1<<bit);
-                bit++;
-            }
-
-            data_array[i]= byte;
-        }
-
-    }
-     /* The for loop here is used to reverse the bits for the x and y values retured
-           by the controller. I am not entirely sure of the format. I'm missing a bit
-           somewhere.. Values don't range from -127..128. */
         x=y=0;
         for (i=0;i<=7;i++) {
             if (controls.array[2] & (1 << i))
@@ -184,6 +203,8 @@
         data_array[3]=y;
     return n;
 }
+
+
 /* void send_byte(unsigned char byte) is used to send a single
    byte to the controller.
  */
@@ -216,8 +237,8 @@
 
 int main() {
     inout.mode(OpenDrain);           // Must use open-drain for N64 Controller!
-
-    uint32_t i, previous_result=0;                           // Used for the bit-shifting for x and y values
+    event_irq_init();
+    uint32_t previous_result=0;                           // Used for the bit-shifting for x and y values
     send_byte(RESET_CONTROLLER);
               wait_ms(10);
     while (1) {