Pitch control for Recorder

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@2267 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Linus Nielsen Feltzing 2002-09-12 12:25:44 +00:00
parent 174f4945f3
commit 5ed78ea80c
2 changed files with 23 additions and 0 deletions

View file

@ -1787,6 +1787,26 @@ void mpeg_sound_channel_config(int configuration)
#endif
}
#ifdef HAVE_MAS3587F
/* This function works by telling the decoder that we have another
crystal frequency than we actually have. It will adjust its internal
parameters and the result is that the audio is played at another pitch */
void mpeg_set_pitch(int percent)
{
unsigned long val;
/* Calculate the new (bogus) frequency */
val = 18432 + (18432*percent/100);
mas_writemem(MAS_BANK_D0,0x7f3,&val,1);
/* We must tell the MAS that the frequency has changed.
This will unfortunately cause a short silence. */
val = 0x25;
mas_writemem(MAS_BANK_D0,0x7f1,&val,1);
}
#endif
void mpeg_init(int volume, int bass, int treble, int balance, int loudness, int bass_boost, int avc)
{
#ifdef SIMULATOR

View file

@ -41,6 +41,9 @@ char *mpeg_sound_unit(int setting);
int mpeg_sound_numdecimals(int setting);
struct mp3entry* mpeg_current_track(void);
bool mpeg_has_changed_track(void);
#ifdef HAVE_MAS3587F
void mpeg_set_pitch(int percent);
#endif
#define SOUND_VOLUME 0
#define SOUND_BASS 1