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Diffstat (limited to 'protocol/lufa/midi/sysex_tools.c')
-rwxr-xr-xprotocol/lufa/midi/sysex_tools.c99
1 files changed, 99 insertions, 0 deletions
diff --git a/protocol/lufa/midi/sysex_tools.c b/protocol/lufa/midi/sysex_tools.c
new file mode 100755
index 0000000000..7563a3e2aa
--- /dev/null
+++ b/protocol/lufa/midi/sysex_tools.c
@@ -0,0 +1,99 @@
+//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/>.
+
+#include "sysex_tools.h"
+
+uint16_t sysex_encoded_length(uint16_t decoded_length){
+ uint8_t remainder = decoded_length % 7;
+ if (remainder)
+ return (decoded_length / 7) * 8 + remainder + 1;
+ else
+ return (decoded_length / 7) * 8;
+}
+
+uint16_t sysex_decoded_length(uint16_t encoded_length){
+ uint8_t remainder = encoded_length % 8;
+ if (remainder)
+ return (encoded_length / 8) * 7 + remainder - 1;
+ else
+ return (encoded_length / 8) * 7;
+}
+
+uint16_t sysex_encode(uint8_t *encoded, const uint8_t *source, const uint16_t length){
+ uint16_t encoded_full = length / 7; //number of full 8 byte sections from 7 bytes of input
+ uint16_t i,j;
+
+ //fill out the fully encoded sections
+ for(i = 0; i < encoded_full; i++) {
+ uint16_t encoded_msb_idx = i * 8;
+ uint16_t input_start_idx = i * 7;
+ encoded[encoded_msb_idx] = 0;
+ for(j = 0; j < 7; j++){
+ uint8_t current = source[input_start_idx + j];
+ encoded[encoded_msb_idx] |= (0x80 & current) >> (1 + j);
+ encoded[encoded_msb_idx + 1 + j] = 0x7F & current;
+ }
+ }
+
+ //fill out the rest if there is any more
+ uint8_t remainder = length % 7;
+ if (remainder) {
+ uint16_t encoded_msb_idx = encoded_full * 8;
+ uint16_t input_start_idx = encoded_full * 7;
+ encoded[encoded_msb_idx] = 0;
+ for(j = 0; j < remainder; j++){
+ uint8_t current = source[input_start_idx + j];
+ encoded[encoded_msb_idx] |= (0x80 & current) >> (1 + j);
+ encoded[encoded_msb_idx + 1 + j] = 0x7F & current;
+ }
+ return encoded_msb_idx + remainder + 1;
+ } else {
+ return encoded_full * 8;
+ }
+}
+
+uint16_t sysex_decode(uint8_t *decoded, const uint8_t *source, const uint16_t length){
+ uint16_t decoded_full = length / 8;
+ uint16_t i,j;
+
+ if (length < 2)
+ return 0;
+
+ //fill out the fully encoded sections
+ for(i = 0; i < decoded_full; i++) {
+ uint16_t encoded_msb_idx = i * 8;
+ uint16_t output_start_index = i * 7;
+ for(j = 0; j < 7; j++){
+ decoded[output_start_index + j] = 0x7F & source[encoded_msb_idx + j + 1];
+ decoded[output_start_index + j] |= (0x80 & (source[encoded_msb_idx] << (1 + j)));
+ }
+ }
+ uint8_t remainder = length % 8;
+ if (remainder) {
+ uint16_t encoded_msb_idx = decoded_full * 8;
+ uint16_t output_start_index = decoded_full * 7;
+ for(j = 0; j < (remainder - 1); j++) {
+ decoded[output_start_index + j] = 0x7F & source[encoded_msb_idx + j + 1];
+ decoded[output_start_index + j] |= (0x80 & (source[encoded_msb_idx] << (1 + j)));
+ }
+ return decoded_full * 7 + remainder - 1;
+ } else {
+ return decoded_full * 7;
+ }
+}
+