c/ghetto-sound-system/ftdi-midi.c

   1 #include <stdio.h>
   2 #include <unistd.h>
   3 #include <alsa/asoundlib.h>
   4 #include <ftdi.h>
   5
   6
   7 #define BAUD 31250
   8 #define BUFFER_SIZE 1
   9 #define LATENCY 0
  10
  11 static snd_rawmidi_t *midi_in, *midi_out;
  12 struct ftdi_context ftdi;
  13
  14 int main(void) {
  15
  16
  17         snd_rawmidi_open(&midi_in, &midi_out, "virtual", SND_RAWMIDI_NONBLOCK);
  18         //snd_rawmidi_open(&midi_in, &midi_out, "virtual", 0);
  19
  20
  21         if (ftdi_init( &ftdi )) {
  22                 fprintf(stderr,  "usb - init error !\n");
  23                 return 1;
  24         }
  25
  26         if (ftdi_usb_open(&ftdi, 0x0403, 0x6001)) {
  27                 fprintf(stderr,  "usb - open error (cannot find?) !\n");
  28                 fprintf(stderr, "ftdi_usb_open failed, error (%s)\n", ftdi_get_error_string(&ftdi));
  29                 ftdi_deinit( &ftdi );
  30                 return 2;
  31         }
  32
  33         if (ftdi_usb_reset( &ftdi )) {
  34                 fprintf(stderr,  "usb - reset error !\n");
  35                 ftdi_usb_close( &ftdi );
  36                 ftdi_deinit( &ftdi );
  37                 return 3;
  38         }
  39
  40         ftdi_disable_bitbang( &ftdi );
  41         ftdi_set_baudrate(&ftdi, BAUD);
  42
  43         unsigned char buf[BUFFER_SIZE];
  44         int ret;
  45         while(1) {
  46                 //FTDI2MIDI
  47                 ret = ftdi_read_data(&ftdi, buf, BUFFER_SIZE);
  48                 if(ret < 0) break;
  49                 if(ret > 0) snd_rawmidi_write(midi_out, buf, BUFFER_SIZE);
  50
  51                 //MIDI2FTDI
  52                 /*
  53                 ret = snd_rawmidi_read(midi_in, buf,BUFFER_SIZE);
  54                 if(ret < 0 && ret != -EAGAIN) break;
  55                 if(ret > 0) ftdi_write_data(&ftdi, buf,BUFFER_SIZE);
  56                 */
  57                 usleep(LATENCY);
  58         }
  59         exit(0);
  60 }