diff options
Diffstat (limited to 'src/mame/audio/beezer.c')
-rw-r--r-- | src/mame/audio/beezer.c | 33 |
1 files changed, 16 insertions, 17 deletions
diff --git a/src/mame/audio/beezer.c b/src/mame/audio/beezer.c index 69a5326f5d2..0b8cce14277 100644 --- a/src/mame/audio/beezer.c +++ b/src/mame/audio/beezer.c @@ -62,9 +62,9 @@ * *************************************/ -#define CRYSTAL_OSC (XTAL_12MHz) -#define SH6840_CLOCK (CRYSTAL_OSC / 12) -#define MULTIPLEX_FREQ (SH6840_CLOCK / 16) +#define CRYSTAL_OSC (XTAL_12MHz) +#define SH6840_CLOCK (CRYSTAL_OSC / 12) +#define MULTIPLEX_FREQ (SH6840_CLOCK / 16) /************************************* * @@ -75,12 +75,12 @@ /* 6840 variables */ struct sh6840_timer_channel { - UINT8 cr; - UINT8 state; - UINT8 leftovers; - UINT16 timer; - UINT32 clocks; - UINT8 int_flag; + UINT8 cr; + UINT8 state; + UINT8 leftovers; + UINT16 timer; + UINT32 clocks; + UINT8 int_flag; union { #ifdef LSB_FIRST @@ -217,7 +217,7 @@ INLINE int sh6840_update_noise(beezer_sound_state *state, int clocks) { state->m_sh6840_LFSR_clocks = 0; /* shift the LFSR. finally or in the result and see if we've - * had a 0->1 transition */ + * had a 0->1 transition */ newxor = (((state->m_sh6840_LFSR&0x10000)?1:0) ^ ((state->m_sh6840_LFSR&0x2000)?1:0))?1:0; state->m_sh6840_LFSR <<= 1; state->m_sh6840_LFSR |= newxor; @@ -353,11 +353,11 @@ static STREAM_UPDATE( beezer_stream_update ) /* stash */ /* each sample feeds an xor bit on the sign bit of a sign-magnitude (NOT 2'S COMPLEMENT) - * DAC. This requires some rather convoluted processing: - * samplex*0x80 brings the sample to the sign bit - * state->m_sh6840_volume[x]&0x80 pulls the sign bit from the dac sample - * state->m_sh6840_volume[x]&0x7F pulls the magnitude from the dac sample - */ + * DAC. This requires some rather convoluted processing: + * samplex*0x80 brings the sample to the sign bit + * state->m_sh6840_volume[x]&0x80 pulls the sign bit from the dac sample + * state->m_sh6840_volume[x]&0x7F pulls the magnitude from the dac sample + */ sample += (((sample0*0x80)^(state->m_sh6840_volume[0]&0x80))?-1:1)*(state->m_sh6840_volume[0]&0x7F); sample += (((sample1*0x80)^(state->m_sh6840_volume[1]&0x80))?-1:1)*(state->m_sh6840_volume[1]&0x7F); sample += (((sample2*0x80)^(state->m_sh6840_volume[2]&0x80))?-1:1)*(state->m_sh6840_volume[2]&0x7F); @@ -398,7 +398,7 @@ const device_type BEEZER = &device_creator<beezer_sound_device>; beezer_sound_device::beezer_sound_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : device_t(mconfig, BEEZER, "beezer SFX", tag, owner, clock), - device_sound_interface(mconfig, *this) + device_sound_interface(mconfig, *this) { m_token = global_alloc_clear(beezer_sound_state); } @@ -602,4 +602,3 @@ WRITE8_DEVICE_HANDLER( beezer_sfxctrl_w ) state->m_stream->update(); state->m_sh6840_volume[offset] = data; } - |