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How to divide the decimal value of the MIDI tonal bend into 2 divided 7-bit values?

I'm trying to create a kind of custom midi player, for this I use an array that has already correctly memorized the data of midi messages, for example:

int array[3000][4]={{time,status,data1,data2},{...},...}

when I want my program to send a midi message (so that it can be played) I call this array and make the necessary differences between note / shutdown, tone skew, etc. The value of the pitch (in the range from 0 to 16383, but usually around 8192, which means there is no pitch shift), is stored in data1 (array [i] [2]). To convert from int to two 7 bit values ​​to go to midiOutShortMsg (), I used the code I found here . Here is the code I'm actually using:

union { unsigned long word; unsigned char data[4]; } message;
int main(int argc, char** argv) {
    int midiport; // select which MIDI output port to open
    uint16_t bend;
    int flag,u;    // monitor the status of returning functions
    uint16_t mask = 0x007F;
    HMIDIOUT device;    // MIDI device interface for sending MIDI output
    message.data[0] = 0x90;  
    message.data[1] = 60;    
    message.data[2] = 100;   
    message.data[3] = 0;     // Unused parameter


// Assign the MIDI output port number (from input or default to 0)
if (!midiOutGetNumDevs()){
    printf("non ci sono devices");
}
if (argc < 2) {
    midiport = 0;
}
else {
    midiport = 0;
}
printf("MIDI output port set to %d.\n", midiport);

// Open the MIDI output port
flag = midiOutOpen(&device, midiport, 0, 0, CALLBACK_NULL);
if (flag != MMSYSERR_NOERROR) {
    printf("Error opening MIDI Output.\n");
    return 1;
}i = 0;
message.data[0] = 0xC0;
message.data[1] = 25;
message.data[2] = 0;
flag = midiOutShortMsg(device, message.word); //program change to steel guitar
if (flag != MMSYSERR_NOERROR) {
    printf("Warning: MIDI Output is not open.\n");
}
while (1){
    if (array[i][1] == 1) { //note on 
        this_works();i++;
    }
    else if (array[i][1] == 0){//note off
        this_also_works();i++;
    }
    else if (array[i][1] == 2){//pitch bend
        while (array[i][1] == 2){
            Sleep(10);
            message.data[0] = 0xE0;
            bend = (uint16_t) array[i][2];
            message.data[1] = bend & mask;
            message.data[2] = (bend & (mask << 7)) >> 7;
            printf("bending %d, %d\n", message.data[1],message.data[2]); 
            flag = midiOutShortMsg(device, message.word);
            if (flag != MMSYSERR_NOERROR) {
                printf("Warning: MIDI Output is not open.\n");
            }i++;
        }
    }
}}

printf ( "bending% d,% d" ) % d 0, , . , midi, 7- , , .

+4
1

( message.data [1]) LSB, data2 (message.data [2]) MSB. C, - :

(byte) data2 = pitchbend >> 7
(byte) data1 = pitchbend & 0x7F

:

  • MSB: 7
  • LSB: pitchbend AND 127

, ( , , ), :

pitchbend = (data2 * 128) + data1

: , , , . IE:

uint16_t mask = 0x007F;
bend = (uint16_t) array[i][2];

message.data[1] = bend & mask;
message.data[2] = (bend & (mask << 7)) >> 7;

array[i][2] ? , 128, , LSB (message.data[1]) . , , MIDI .

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