Diff: nine_ring/nine_ring.cpp

Revision:

0:c050eb7b0c10

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nine_ring/nine_ring.cpp	Mon Jul 13 07:54:11 2015 +0000
@@ -0,0 +1,94 @@
+#include "mbed.h"
+#include "nine_ring.h"
+/*
+J.J.Trinder, based on original code for midi projects 199X
+updateded sometime to the MBED
+
+Yeh its atad klunky, it works and is useful to explain things to people...
+*/
+#define _PC
+NRing::NRing()
+{
+   ring_init();
+}
+
+
+
+/*======================================================================*/
+/* implementation of Ringbuffer                     */
+/*======================================================================*/
+ /** Init the indexes
+        
+*/
+void NRing::ring_init(void)
+{
+    inIndex = 0;
+    inCount = 0;
+}
+
+/*======================================================================*/
+/* RingWriteToBuffer                     */
+/*======================================================================*/
+/**
+Write value (long) into the ring buffer
+@param <n> A long value to store in the ring buffer
+*/
+//add critical section ie disable interrupts while fiddling with buffers
+int NRing::RingWriteToBuffer(long n)
+{
+   // printf("WriteInBuffer%d",inCount);
+__disable_irq();    // Disable Interrupts
+ 
+// do something that can't be interrupted
+   opBuffer[inIndex] = n;
+    inCount++;
+    inIndex++;
+    if (inIndex >= buff_size)
+        inIndex = 0;
+   
+ 
+__enable_irq();     // Enable Interrupts 
+  //printf("ZWriteInBuffer%d\n",inCount);       
+    return 0;
+}
+
+
+//todo fix this as we dont want to do this
+/*======================================================================*/
+/* return current count of stuff in buffer           */
+/*======================================================================*/
+int NRing::ring_count()
+{
+   // printf("InCount %d",inCount);
+    return (inCount);
+}
+
+
+//todo fix this as we dont want to do this
+/*======================================================================*/
+/* Output whats remaining....            */
+/*======================================================================*/
+long NRing::get_next()
+{
+   
+    long toSend;
+#ifdef _PC
+    printf("\nCall in %x out %x count %x",inIndex,outIndex, inCount);
+#endif
+    if (inCount == 0)
+        return -1;     /* nowt to send */
+    __disable_irq();    // Disable Interrupts    
+    toSend = opBuffer[outIndex];
+
+#ifdef _PC
+    printf(" <%i> ",toSend);
+#endif
+ 
+    inCount--;
+    outIndex++;
+    if (outIndex >=buff_size)
+        outIndex = 0;
+    __enable_irq();     // Enable Interrupts       
+    return toSend;
+}
+