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authorYves Fischer <yvesf-git@xapek.org>2011-10-11 21:50:49 +0200
committerYves Fischer <yvesf-git@xapek.org>2011-10-11 21:50:49 +0200
commit324c5ba9098c1010d0aa8c1e26b95509878ce9f2 (patch)
treef6ef2d537decaa2e1af6d4b9c4c31161b22333ec /firmware/fifo.h
downloadmini-octopus-324c5ba9098c1010d0aa8c1e26b95509878ce9f2.tar.gz
mini-octopus-324c5ba9098c1010d0aa8c1e26b95509878ce9f2.zip
Mini-Octopus build from r@171
Diffstat (limited to 'firmware/fifo.h')
-rw-r--r--firmware/fifo.h75
1 files changed, 75 insertions, 0 deletions
diff --git a/firmware/fifo.h b/firmware/fifo.h
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--- /dev/null
+++ b/firmware/fifo.h
@@ -0,0 +1,75 @@
+#ifndef _FIFO_H_
+#define _FIFO_H_
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+typedef struct
+{
+ uint8_t volatile count; // # Zeichen im Puffer
+ uint8_t size; // Puffer-Größe
+ uint8_t *pread; // Lesezeiger
+ uint8_t *pwrite; // Schreibzeiger
+ uint8_t read2end, write2end; // # Zeichen bis zum Überlauf Lese-/Schreibzeiger
+} fifo_t;
+
+extern void fifo_init (fifo_t*, uint8_t* buf, const uint8_t size);
+extern uint8_t fifo_put (fifo_t*, const uint8_t data);
+extern uint8_t fifo_get_wait (fifo_t*);
+extern int fifo_get_nowait (fifo_t*);
+
+static inline uint8_t
+_inline_fifo_put (fifo_t *f, const uint8_t data)
+{
+ if (f->count >= f->size)
+ return 0;
+
+ uint8_t * pwrite = f->pwrite;
+
+ *(pwrite++) = data;
+
+ uint8_t write2end = f->write2end;
+
+ if (--write2end == 0)
+ {
+ write2end = f->size;
+ pwrite -= write2end;
+ }
+
+ f->write2end = write2end;
+ f->pwrite = pwrite;
+
+ uint8_t sreg = SREG;
+ cli();
+ f->count++;
+ SREG = sreg;
+
+ return 1;
+}
+
+static inline uint8_t
+_inline_fifo_get (fifo_t *f)
+{
+ uint8_t *pread = f->pread;
+ uint8_t data = *(pread++);
+ uint8_t read2end = f->read2end;
+
+ if (--read2end == 0)
+ {
+ read2end = f->size;
+ pread -= read2end;
+ }
+
+ f->pread = pread;
+ f->read2end = read2end;
+
+ uint8_t sreg = SREG;
+ cli();
+ f->count--;
+ SREG = sreg;
+
+ return data;
+}
+
+#endif /* _FIFO_H_ */
+