--- /dev/null
+/*---------------------------------------------------------------------------*\
+
+ FILE........: fmfsk.h
+ AUTHOR......: Brady O'Brien
+ DATE CREATED: 6 February 2016
+
+ C Implementation of 2FSK+Manchester over FM modulator/demodulator, based
+ on mancyfsk.m and fmfsk.m
+
+\*---------------------------------------------------------------------------*/
+
+/*
+ Copyright (C) 2016 David Rowe
+
+ All rights reserved.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License version 2.1, as
+ published by the Free Software Foundation. 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 Lesser General Public License
+ along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __C2FMFSK_H
+#define __C2FMFSK_H
+#include <stdint.h>
+#include "comp.h"
+
+/*
+ * fm-me-2fsk state
+ */
+struct FMFSK{
+ /* Static fmfsk parameters */
+ int Rb; /* Manchester-encoded bitrate */
+ int Rs; /* Raw modem symbol rate */
+ int Fs; /* Sample rate */
+ int Ts; /* Samples-per-symbol */
+ int N; /* Sample processing buffer size */
+ int nsym; /* Number of raw modem symbols processed per demod call */
+ int nbit; /* Number of bits spit out per demod call */
+ int nmem; /* Number of samples kept around between demod calls */
+
+ /* State kept by demod */
+ int nin; /* Number of samples to be demod-ed the next cycle */
+ int lodd; /* Last integrated sample for odd bitstream generation */
+ float * oldsamps; /* Memory of old samples to make clock-offset-tolerance possible */
+
+};
+
+/*
+ * Create a new fmfsk modem instance.
+ *
+ * int Fs - sample rate
+ * int Rb - non-manchester bitrate
+ * returns - new struct FMFSK on sucess, NULL on failure
+ */
+struct FMFSK * fmfsk_create(int Fs,int Rb);
+
+/*
+ * Destroys an fmfsk modem and deallocates memory
+ */
+void fmfsk_destroy(struct FMFSK *fmfsk);
+
+/*
+ * Returns the number of samples that must be fed to fmfsk_demod the next
+ * cycle
+ */
+uint32_t fmfsk_nin(struct FMFSK *fmfsk);
+
+/*
+ * Modulates nbit bits into N samples to be sent through an FM radio
+ *
+ * struct FSK *fsk - FSK config/state struct, set up by fsk_create
+ * float mod_out[] - Buffer for N samples of modulated FMFSK
+ * uint8_t tx_bits[] - Buffer containing Nbits unpacked bits
+ */
+void fmfsk_mod(struct FMFSK *fmfsk, float fmfsk_out[],uint8_t bits_in[]);
+
+
+/*
+ * Demodulate some number of FMFSK samples. The number of samples to be
+ * demodulated can be found by calling fmfsk_nin().
+ *
+ * struct FMFSK *fsk - FMFSK config/state struct, set up by fsk_create
+ * uint8_t rx_bits[] - Buffer for nbit unpacked bits to be written
+ * float fsk_in[] - nin samples of modualted FMFSK from an FM radio
+ */
+void fmfsk_demod(struct FMFSK *fmfsk, uint8_t rx_bits[],float fmfsk_in[]);
+
+#endif