MIDIMessage.h

00001 /* Copyright (c) 2010-2011 mbed.org, MIT License
00002 *
00003 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00004 * and associated documentation files (the "Software"), to deal in the Software without
00005 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
00006 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
00007 * Software is furnished to do so, subject to the following conditions:
00008 *
00009 * The above copyright notice and this permission notice shall be included in all copies or
00010 * substantial portions of the Software.
00011 *
00012 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00013 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00014 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00015 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00016 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00017 */
00018 
00019 #ifndef MIDIMESSAGE_H
00020 #define MIDIMESSAGE_H
00021 
00022 #include "mbed.h"
00023 
00024 #define MAX_MIDI_MESSAGE_SIZE 256 // Max message size. SysEx can be up to 65536 but 256 should be fine for most usage
00025 
00026 // MIDI Message Format
00027 //
00028 // [ msg(4) | channel(4) ] [ 0 | n(7) ] [ 0 | m(7) ]
00029 //
00030 // MIDI Data Messages (Channel Specific)
00031 //
00032 // Message               msg n          m
00033 // ---------------------------------------------
00034 // Note Off              0x8 Key        Velocity
00035 // Note On               0x9 Key        Velocity
00036 // Polyphonic Aftertouch 0xA Key        Pressure
00037 // Control Change        0xB Controller Value
00038 // Program Change        0xC Program    -
00039 // Channel Aftertouch    0xD Pressure   -
00040 // Pitch Wheel           0xE LSB        MSB
00041 
00042 #define CABLE_NUM (0<<4)
00043 
00044 /** A MIDI message container */
00045 class MIDIMessage {
00046 public:
00047     MIDIMessage() : length(4) {}
00048 
00049     MIDIMessage(uint8_t *buf) : length(4) {
00050         for (int i = 0; i < 4; i++)
00051             data[i] = buf[i];
00052     }
00053 
00054     // New constructor, buf is a true MIDI message (not USBMidi message) and buf_len true message length.
00055     MIDIMessage(uint8_t *buf, int buf_len) {
00056         length=buf_len+1;
00057         // first byte keeped for retro-compatibility
00058         data[0]=0;
00059 
00060         for (int i = 0; i < buf_len; i++)
00061             data[i+1] = buf[i];
00062     }
00063 
00064     // create messages
00065 
00066     /** Create a NoteOff message
00067      * @param key Key ID
00068      * @param velocity Key velocity (0-127, default = 127)
00069      * @param channel Key channel (0-15, default 0)
00070      * @returns A MIDIMessage
00071      */
00072     static MIDIMessage NoteOff(int key, int velocity = 127, int channel = 0) {
00073         MIDIMessage msg;
00074         msg.data[0] = CABLE_NUM | 0x08;
00075         msg.data[1] = 0x80 | (channel & 0x0F);
00076         msg.data[2] = key & 0x7F;
00077         msg.data[3] = velocity & 0x7F;
00078         return msg;
00079     }
00080 
00081     /** Create a NoteOn message
00082      * @param key Key ID
00083      * @param velocity Key velocity (0-127, default = 127)
00084      * @param channel Key channel (0-15, default 0)
00085      * @returns A MIDIMessage
00086      */
00087     static MIDIMessage NoteOn(int key, int velocity = 127, int channel = 0) {
00088         MIDIMessage msg;
00089         msg.data[0] = CABLE_NUM | 0x09;
00090         msg.data[1] = 0x90 | (channel & 0x0F);
00091         msg.data[2] = key & 0x7F;
00092         msg.data[3] = velocity & 0x7F;
00093         return msg;
00094     }
00095 
00096     /** Create a PolyPhonic Aftertouch message
00097      * @param key Key ID
00098      * @param pressure Aftertouch pressure (0-127)
00099      * @param channel Key channel (0-15, default 0)
00100      * @returns A MIDIMessage
00101      */
00102     static MIDIMessage PolyphonicAftertouch(int key, int pressure, int channel = 0) {
00103         MIDIMessage msg;
00104         msg.data[0] = CABLE_NUM | 0x0A;
00105         msg.data[1] = 0xA0 | (channel & 0x0F);
00106         msg.data[2] = key & 0x7F;
00107         msg.data[3] = pressure & 0x7F;
00108         return msg;
00109     }
00110 
00111     /** Create a Control Change message
00112      * @param control Controller ID
00113      * @param value Controller value (0-127)
00114      * @param channel Controller channel (0-15, default 0)
00115      * @returns A MIDIMessage
00116      */
00117     static MIDIMessage ControlChange(int control, int value, int channel = 0) {
00118         MIDIMessage msg;
00119         msg.data[0] = CABLE_NUM | 0x0B;
00120         msg.data[1] = 0xB0 | (channel & 0x0F);
00121         msg.data[2] = control & 0x7F;
00122         msg.data[3] = value & 0x7F;
00123         return msg;
00124     }
00125 
00126     /** Create a Program Change message
00127      * @param program Program ID
00128      * @param channel Channel (0-15, default 0)
00129      * @returns A MIDIMessage
00130      */
00131     static MIDIMessage ProgramChange(int program, int channel = 0) {
00132         MIDIMessage msg;
00133         msg.data[0] = CABLE_NUM | 0x0C;
00134         msg.data[1] = 0xC0 | (channel & 0x0F);
00135         msg.data[2] = program & 0x7F;
00136         msg.data[3] = 0x00;
00137         return msg;
00138     }
00139 
00140     /** Create a Channel Aftertouch message
00141      * @param pressure Pressure
00142      * @param channel Key channel (0-15, default 0)
00143      * @returns A MIDIMessage
00144      */
00145     static MIDIMessage ChannelAftertouch(int pressure, int channel = 0) {
00146         MIDIMessage msg;
00147         msg.data[0] = CABLE_NUM | 0x0D;
00148         msg.data[1] = 0xD0 | (channel & 0x0F);
00149         msg.data[2] = pressure & 0x7F;
00150         msg.data[3] = 0x00;
00151         return msg;
00152     }
00153 
00154     /** Create a Pitch Wheel message
00155      * @param pitch Pitch (-8192 - 8191, default = 0)
00156      * @param channel Channel (0-15, default 0)
00157      * @returns A MIDIMessage
00158      */
00159     static MIDIMessage PitchWheel(int pitch = 0, int channel = 0) {
00160         MIDIMessage msg;
00161         int p = pitch + 8192;    // 0 - 16383, 8192 is center
00162         msg.data[0] = CABLE_NUM | 0x0E;
00163         msg.data[1] = 0xE0 | (channel & 0x0F);
00164         msg.data[2] = p & 0x7F;
00165         msg.data[3] = (p >> 7) & 0x7F;
00166         return msg;
00167     }
00168 
00169     /** Create an All Notes Off message
00170      * @param channel Channel (0-15, default 0)
00171      * @returns A MIDIMessage
00172      */
00173     static MIDIMessage AllNotesOff(int channel = 0) {
00174         return ControlChange(123, 0, channel);
00175     }
00176 
00177      /** Create a SysEx message
00178      * @param data SysEx data (including 0xF0 .. 0xF7)
00179      * @param len SysEx data length
00180      * @returns A MIDIMessage
00181      */
00182     static MIDIMessage SysEx(uint8_t *data, int len) {
00183         MIDIMessage msg=MIDIMessage(data,len);
00184         return msg;
00185     }
00186 
00187     // decode messages
00188 
00189     /** MIDI Message Types */
00190     enum MIDIMessageType {
00191         ErrorType,
00192         NoteOffType,
00193         NoteOnType,
00194         PolyphonicAftertouchType,
00195         ControlChangeType,
00196         ProgramChangeType,
00197         ChannelAftertouchType,
00198         PitchWheelType,
00199         AllNotesOffType,
00200         SysExType
00201     };
00202 
00203     /** Read the message type
00204      * @returns MIDIMessageType
00205      */
00206     MIDIMessageType type() {
00207         switch((data[1] >> 4) & 0xF) {
00208             case 0x8: return NoteOffType;
00209             case 0x9: return NoteOnType;
00210             case 0xA: return PolyphonicAftertouchType;
00211             case 0xB:
00212                 if(controller() < 120) { // standard controllers
00213                     return ControlChangeType;
00214                 } else if(controller() == 123) {
00215                     return AllNotesOffType;
00216                 } else {
00217                     return ErrorType; // unsupported atm
00218                 }
00219             case 0xC: return ProgramChangeType;
00220             case 0xD: return ChannelAftertouchType;
00221             case 0xE: return PitchWheelType;
00222             case 0xF: return SysExType;
00223             default: return ErrorType;
00224         }
00225     }
00226 
00227     /** Read the channel number */
00228     int channel() {
00229         return (data[1] & 0x0F);
00230     }
00231 
00232     /** Read the key ID */
00233     int key() {
00234         return (data[2] & 0x7F);
00235     }
00236 
00237     /** Read the velocity */
00238     int velocity() {
00239         return (data[3] & 0x7F);
00240     }
00241 
00242     /** Read the controller value */
00243     int value() {
00244         return (data[3] & 0x7F);
00245     }
00246 
00247     /** Read the aftertouch pressure */
00248     int pressure() {
00249         if(type() == PolyphonicAftertouchType) {
00250             return (data[3] & 0x7F);
00251         } else {
00252             return (data[2] & 0x7F);
00253         }
00254     }
00255 
00256     /** Read the controller number */
00257     int controller() {
00258         return (data[2] & 0x7F);
00259     }
00260 
00261     /** Read the program number */
00262     int program() {
00263         return (data[2] & 0x7F);
00264     }
00265 
00266     /** Read the pitch value */
00267     int pitch() {
00268         int p = ((data[3] & 0x7F) << 7) | (data[2] & 0x7F);
00269         return p - 8192; // 0 - 16383, 8192 is center
00270     }
00271 
00272     uint8_t data[MAX_MIDI_MESSAGE_SIZE+1];
00273     uint8_t length;
00274 };
00275 
00276 #endif