diff options
| author | Keith Packard <keithp@keithp.com> | 2010-10-31 22:51:48 -0700 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2010-10-31 22:51:48 -0700 |
| commit | c983b2d670dfe6bace2c6d776e34eaafa25db9bb (patch) | |
| tree | 97c4fc61432b0a09b7a31211cbc08e6496f6ba4c /src/ao_audio.c | |
| parent | 6b17b75ed5dc4e4fcc7278c715479bb921b644d5 (diff) | |
teleterra: audio amp is enabled by bringing audio_en (P2_4) high
The external audio amplifier is placed in 'suspend' mode most of the
time to save power. When audio is being sent, turn it on.
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src/ao_audio.c')
| -rw-r--r-- | src/ao_audio.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/src/ao_audio.c b/src/ao_audio.c index 0d521973..5d8fdfb5 100644 --- a/src/ao_audio.c +++ b/src/ao_audio.c @@ -584,6 +584,12 @@ ao_audio_send(__xdata uint8_t *samples, uint16_t nsamples) __reentrant { ao_mutex_get(&ao_audio_mutex); +#if AUDIO_STANDBY_ON_P2_4 + /* + * Turn on the audio amp + */ + P2_4 = 1; +#endif /* * Turn on timer 4. Free running from 0 to 0xff, with P2_0 * 'on' interval controlled by the value in T4CC0. Run this @@ -641,6 +647,12 @@ ao_audio_send(__xdata uint8_t *samples, uint16_t nsamples) __reentrant P2_0 = 0; P2SEL = (P2SEL & ~P2SEL_SELP2_0_MASK) | P2SEL_SELP2_0_GPIO; +#if AUDIO_STANDBY_ON_P2_4 + /* + * Turn off the audio amp + */ + P2_4 = 0; +#endif ao_mutex_put(&ao_audio_mutex); } @@ -665,6 +677,12 @@ ao_audio_init(void) P2SEL = (P2SEL & ~P2SEL_SELP2_0_MASK) | P2SEL_SELP2_0_GPIO; PERCFG = (PERCFG & ~PERCFG_T4CFG_ALT_MASK) | PERCFG_T4CFG_ALT_2; +#if AUDIO_STANDBY_ON_P2_4 + P2_4 = 0; + P2SEL &= ~P2SEL_SELP2_4_PERIPHERAL; + P2DIR |= (1 << 4); +#endif + /* Timer 3 is used to clock the DMA transfers from the audio data buffer * to the timer 4 */ |