First version of the AX25 TX functionality.

AX25Defines.h

@@ -0,0 +1,36 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#if !defined(AX25DEFINES_H)
+#define  AX25DEFINES_H
+
+const uint8_t AX25_RADIO_SYMBOL_LENGTH = 20U;      // At 24 kHz sample rate
+
+const uint8_t AX25_FRAME_START = 0x7EU;
+const uint8_t AX25_FRAME_END   = 0x7EU;
+const uint8_t AX25_FRAME_ABORT = 0xFEU;
+
+const uint8_t AX25_MAX_ONES    = 5U;
+
+const uint16_t AX25_MIN_FRAME_LENGTH = 17U;        // Callsign (7) + Callsign (7) + Control (1) + Checksum (2)
+
+const uint16_t AX25_MAX_FRAME_LENGTH = 294U;       // Callsign (7) + Callsign (7) + 3 Digipeaters (21) +
+                                                   // Control (1) + Data (256) + Checksum (2)
+
+#endif
+