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Diffstat (limited to 'src/mame/audio/geebee.c')
-rw-r--r--src/mame/audio/geebee.c32
1 files changed, 15 insertions, 17 deletions
diff --git a/src/mame/audio/geebee.c b/src/mame/audio/geebee.c
index a30cb82cc94..59a51e537a1 100644
--- a/src/mame/audio/geebee.c
+++ b/src/mame/audio/geebee.c
@@ -50,28 +50,28 @@ WRITE8_DEVICE_HANDLER( geebee_sound_w )
if( state->m_sound_latch & 8 )
{
/*
- * R24 is 10k, Rb is 0, C57 is 1uF
- * charge time t1 = 0.693 * (R24 + Rb) * C57 -> 0.22176s
- * discharge time t2 = 0.693 * (Rb) * C57 -> 0
- * Then C33 is only charged via D6 (1N914), not discharged!
- * Decay:
- * discharge C33 (1uF) through R50 (22k) -> 0.14058s
- */
+ * R24 is 10k, Rb is 0, C57 is 1uF
+ * charge time t1 = 0.693 * (R24 + Rb) * C57 -> 0.22176s
+ * discharge time t2 = 0.693 * (Rb) * C57 -> 0
+ * Then C33 is only charged via D6 (1N914), not discharged!
+ * Decay:
+ * discharge C33 (1uF) through R50 (22k) -> 0.14058s
+ */
attotime period = attotime::from_hz(32768) * 14058 / 100000;
state->m_volume_timer->adjust(period, 0, period);
}
else
{
/*
- * discharge only after R49 (100k) in the amplifier section,
- * so the volume shouldn't very fast and only when the signal
- * is gated through 6N (4066).
- * I can only guess here that the decay should be slower,
- * maybe half as fast?
- */
+ * discharge only after R49 (100k) in the amplifier section,
+ * so the volume shouldn't very fast and only when the signal
+ * is gated through 6N (4066).
+ * I can only guess here that the decay should be slower,
+ * maybe half as fast?
+ */
attotime period = attotime::from_hz(32768) * 29060 / 100000;
state->m_volume_timer->adjust(period, 0, period);
- }
+ }
}
static STREAM_UPDATE( geebee_sound_update )
@@ -147,7 +147,7 @@ const device_type GEEBEE = &device_creator<geebee_sound_device>;
geebee_sound_device::geebee_sound_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
: device_t(mconfig, GEEBEE, "Gee Bee Custom", tag, owner, clock),
- device_sound_interface(mconfig, *this)
+ device_sound_interface(mconfig, *this)
{
m_token = global_alloc_clear(geebee_sound_state);
}
@@ -180,5 +180,3 @@ void geebee_sound_device::sound_stream_update(sound_stream &stream, stream_sampl
// should never get here
fatalerror("sound_stream_update called; not applicable to legacy sound devices\n");
}
-
-