Revision 0:3c704483eb79, committed 2014-05-21

Comitter:

gert_lauritsen

Date:

Wed May 21 18:30:45 2014 +0000

Commit message:

Just a simple Fifo

Changed in this revision

diff -r 000000000000 -r 3c704483eb79 fifo.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fifo.cpp	Wed May 21 18:30:45 2014 +0000
@@ -0,0 +1,49 @@
+#include "fifo.h"
+
+fifo::fifo()
+{
+    this->head = 0;
+    this->tail = 0;
+}
+uint32_t fifo::available()
+{
+    return (FIFO_SIZE + this->head - this->tail) % FIFO_SIZE;
+}
+uint32_t fifo::free()
+{
+    return (FIFO_SIZE - 1 - available());
+}
+uint8_t fifo::put(FIFO_TYPE data)
+{
+    uint32_t next;
+
+    // check if FIFO has room
+    next = (this->head + 1) % FIFO_SIZE;
+    if (next == this->tail)
+    {
+        // full
+        return 1;
+    }
+
+    this->buffer[this->head] = data;
+    this->head = next;
+
+    return 0;
+}
+uint8_t fifo::get(FIFO_TYPE* data)
+{
+    uint32_t next;
+
+    // check if FIFO has data
+    if (this->head == this->tail)
+    {
+        return 1; // FIFO empty
+    }
+
+    next = (this->tail + 1) % FIFO_SIZE;
+
+    *data = this->buffer[this->tail];
+    this->tail = next;
+
+    return 0;
+}

diff -r 000000000000 -r 3c704483eb79 fifo.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fifo.h	Wed May 21 18:30:45 2014 +0000
@@ -0,0 +1,23 @@
+#ifndef FIFO_H_
+#define FIFO_H_
+
+#include "LPC17xx.h"
+
+#define FIFO_SIZE 256
+#define FIFO_TYPE uint8_t
+
+class fifo
+{
+    FIFO_TYPE buffer[FIFO_SIZE];
+    uint32_t head, tail;
+
+public:
+    fifo();
+    uint8_t put(FIFO_TYPE data);// returns 0 on success
+    uint8_t get(FIFO_TYPE* data);
+    uint32_t available();
+    uint32_t free();
+};
+
+
+#endif /* FIFO_H_ */