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diff --git a/bootloader/midi/sysex_tools.h b/bootloader/midi/sysex_tools.h
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+//midi for embedded chips,
+//Copyright 2010 Alex Norman
+//
+//This file is part of avr-midi.
+//
+//avr-midi 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 3 of the License, or
+//(at your option) any later version.
+//
+//avr-midi 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 avr-midi.  If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef SYSEX_TOOLS_H
+#define SYSEX_TOOLS_H
+
+#include <inttypes.h>
+
+/**
+ * These functions are for converting data to and from a "midi-safe" format,
+ * which can be use to send data with sysex messages.  Sysex messages may only
+ * contain data where the to bit is not set. 
+ *
+ * A bit "packed" midi message is one that contains all of the data from its
+ * original state, but does not have any of the top bits set.
+ *
+ * Every 7 bytes of unpacked data is converted into 8 bytes of packed data and
+ * visa-versa.  If you'd like to operate on small segments, make sure that you
+ * pack in 7 byte increments and unpack in 8 byte increments.
+ *
+ */
+
+/**
+ * Compute the length of a message after it is packed.
+ *
+ * @param unpacked_length The length, in bytes, of the message to pack.
+ *
+ * @return The length, in bytes, of the message after packing.
+ */
+uint16_t sysex_bit_packed_length(uint16_t unpacked_length);
+
+/**
+ * Compute the length of a message after it is unpacked.
+ *
+ * @param packed_length The length, in bytes, of the packed message.
+ *
+ * @return The length, in bytes, of the message after it is unpacked.
+ */
+uint16_t sysex_bit_unpacked_length(uint16_t packed_length);
+
+/**
+ * Pack data so that it can be transmitted safely in a sysex message.
+ *
+ * @param packed The output data buffer, must be at least sysex_bit_packed_length(length) bytes long.
+ * @param source The input buffer of data to be packed.
+ * @param length The number of bytes from the input buffer to pack.
+ * 
+ * @return number of bytes packed.
+ */
+uint16_t sysex_bit_pack(uint8_t *packed, const uint8_t *source, uint16_t length);
+
+/**
+ * Unpack packed data.
+ *
+ * @param unpacked The output data buffer, must be at least sysex_bit_unpacked_length(length) bytes long.
+ * @param source The input buffer of data to be unpacked.
+ * @param length The number of bytes from the input buffer to unpack.
+ * 
+ * @return number of bytes unpacked.
+ */
+uint16_t sysex_bit_unpack(uint8_t *unpacked, const uint8_t *source, uint16_t length);
+
+#endif