Initial commit

util/CRC-CCIT.c

@@ -0,0 +1,36 @@
+#include "CRC-CCIT.h"
+
+const uint16_t crc_ccit_table[256] PROGMEM = {
+    0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
+    0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
+    0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
+    0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
+    0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
+    0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
+    0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
+    0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
+    0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
+    0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
+    0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
+    0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
+    0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
+    0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
+    0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
+    0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
+    0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
+    0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
+    0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
+    0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
+    0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
+    0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
+    0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
+    0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
+    0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
+    0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
+    0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
+    0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
+    0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
+    0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
+    0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
+    0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78,
+};

util/CRC-CCIT.h

@@ -0,0 +1,18 @@
+// CRC-CCIT Implementation based on work by Francesco Sacchi
+
+#ifndef CRC_CCIT_H
+#define CRC_CCIT_H
+
+#include <stdint.h>
+#include <avr/pgmspace.h>
+
+#define CRC_CCIT_INIT_VAL ((uint16_t)0xFFFF)
+
+extern const uint16_t crc_ccit_table[256];
+
+inline uint16_t update_crc_ccit(uint8_t c, uint16_t prev_crc) {
+    return (prev_crc >> 8) ^ pgm_read_word(&crc_ccit_table[(prev_crc ^ c) & 0xff]);
+}
+
+
+#endif

util/FIFO.h

@@ -0,0 +1,85 @@
+#ifndef UTIL_FIFO_H
+#define UTIL_FIFO_H
+
+#include <stddef.h>
+#include <util/atomic.h>
+
+typedef struct FIFOBuffer
+{
+  unsigned char *begin;
+  unsigned char *end;
+  unsigned char * volatile head;
+  unsigned char * volatile tail;
+} FIFOBuffer;
+
+inline bool fifo_isempty(const FIFOBuffer *f) {
+  return f->head == f->tail;
+}
+
+inline bool fifo_isfull(const FIFOBuffer *f) {
+  return ((f->head == f->begin) && (f->tail == f->end)) || (f->tail == f->head - 1);
+}
+
+inline void fifo_push(FIFOBuffer *f, unsigned char c) {
+  *(f->tail) = c;
+  
+  if (f->tail == f->end) {
+    f->tail = f->begin;
+  } else {
+    f->tail++;
+  }
+}
+
+inline unsigned char fifo_pop(FIFOBuffer *f) {
+  if(f->head == f->end) {
+    f->head = f->begin;
+    return *(f->end);
+  } else {
+    return *(f->head++);
+  }
+}
+
+inline void fifo_flush(FIFOBuffer *f) {
+  f->head = f->tail;
+}
+
+inline bool fifo_isempty_locked(const FIFOBuffer *f) {
+  bool result;
+  ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+    result = fifo_isempty(f);
+  }
+  return result;
+}
+
+inline bool fifo_isfull_locked(const FIFOBuffer *f) {
+  bool result;
+  ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+    result = fifo_isfull(f);
+  }
+  return result;
+}
+
+inline void fifo_push_locked(FIFOBuffer *f, unsigned char c) {
+  ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+    fifo_push(f, c);
+  }
+}
+
+inline unsigned char fifo_pop_locked(FIFOBuffer *f) {
+  unsigned char c;
+  ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+    c = fifo_pop(f);
+  }
+  return c;
+}
+
+inline void fifo_init(FIFOBuffer *f, unsigned char *buffer, size_t size) {
+  f->head = f->tail = f->begin = buffer;
+  f->end = buffer + size -1;
+}
+
+inline size_t fifo_len(FIFOBuffer *f) {
+  return f->end - f->begin;
+}
+
+#endif

util/time.h

@@ -0,0 +1,34 @@
+#ifndef UTIL_TIME_H
+#define UTIL_TIME_H
+
+#include "device.h"
+
+#define DIV_ROUND(dividend, divisor)  (((dividend) + (divisor) / 2) / (divisor))
+#define CLOCK_TICKS_PER_SEC CONFIG_AFSK_DAC_SAMPLERATE
+
+typedef int32_t ticks_t;
+typedef int32_t mtime_t;
+
+volatile ticks_t _clock;
+
+inline ticks_t timer_clock(void) {
+    ticks_t result;
+
+    ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+        result = _clock;
+    }
+
+    return result;
+}
+
+
+inline ticks_t ms_to_ticks(mtime_t ms) {
+    return ms * DIV_ROUND(CLOCK_TICKS_PER_SEC, 1000);
+}
+
+inline void cpu_relax(void) {
+    // Do nothing!
+}
+
+
+#endif