Sprinter/mame
2
0
Fork 0
mirror of https://github.com/holub/mame synced 2025-04-20 15:32:45 +03:00
Code Issues Actions 6 Packages Projects Releases Wiki Activity

dkong.c

Browse Source 
* added equivalence circuit for Sanyo EZV audio amplifier
* Set DK_C159 = 0 to avoid over-aggressive high-pass filter. Solely based on observations. 
* added comment on above to source
* Added define DK_NO_FILTERS to turn of DAC filters and post-mixer filters for debugging
This commit is contained in:
Couriersud 2008-01-13 22:05:46 +00:00
parent 066fa9c096
commit 6113493440
1 changed files with 37 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

55
src/mame/audio/dkong.c
View File

@ -17,6 +17,10 @@
*
****************************************************************/
/* Set to 1 to disable DAC and post-mixer filters */
#define DK_NO_FILTERS (0)
#define ACTIVELOW_PORT_BIT(P,A,D) (((P) & (~(1 << (A)))) | (((D) ^ 1) << (A)))
/* Needed for dkongjr ... FIXME */
@ -99,10 +103,6 @@
*
****************************************************************/
/* Variable components */
#define DK_VR1 RES_K(10)
/* Resistors */
#define DK_R1 RES_K(47)
@ -166,7 +166,7 @@
#define DK_C30 CAP_U(10)
#define DK_C32 CAP_U(10)
#define DK_C34 CAP_N(10)
#define DK_C160 CAP_N(100)
#define DK_C159 CAP_N(0) /* 100nF in Schematics but sound is way off */
/*
@ -215,8 +215,8 @@ static const discrete_mixer_desc dkong_mixer_desc =
{DK_R2, DK_R24, DK_R1, DK_R14},
{0,0,0}, // no variable resistors
{0,0,0}, // no node capacitors
0, DK_VR1,
DK_C160,
0, 0,
DK_C159,
DK_C12,
0, 1};
@ -345,7 +345,11 @@ static DISCRETE_SOUND_START(dkong2b)
DISCRETE_FILTER2(NODE_73, 1, NODE_71, 1916, (1.0/0.74), DISC_FILTER_LOWPASS)
/* Adjustment VR2 */
#if DK_NO_FILTERS
DISCRETE_MULTIPLY(DS_OUT_DAC, 1, NODE_71, DS_ADJ_DAC)
#else
DISCRETE_MULTIPLY(DS_OUT_DAC, 1, NODE_73, DS_ADJ_DAC)
#endif
/************************************************/
/* Amplifier */
@ -356,9 +360,16 @@ static DISCRETE_SOUND_START(dkong2b)
// Amplifier: internal amplifier
DISCRETE_ADDER2(NODE_289,1,NODE_288,5.0*43.0/(100.0+43.0))
DISCRETE_RCINTEGRATE(NODE_294,1,NODE_289,0,150,1000, CAP_U(33),DK_SUP_V,DISC_RC_INTEGRATE_TYPE3)
DISCRETE_CRFILTER(NODE_295,1,NODE_294, 1000, DK_C13)
DISCRETE_OUTPUT(NODE_295, 32767.0/5.0 * 3)
DISCRETE_CRFILTER(NODE_295,1,NODE_294, RES_K(50), DK_C13)
// EZV20 equivalent filter circuit ...
DISCRETE_CRFILTER(NODE_296,1,NODE_295, RES_K(1), CAP_U(4.7))
#if DK_NO_FILTERS
DISCRETE_OUTPUT(NODE_288, 32767.0/5.0 * 10)
#else
DISCRETE_OUTPUT(NODE_296, 32767.0/5.0 * 3)
#endif
DISCRETE_SOUND_END
/****************************************************************
@ -635,6 +646,8 @@ DISCRETE_SOUND_END
#define JR_R9 RES_K(47)
#define JR_R10 RES_K(10)
#define JR_R11 RES_K(20)
#define JR_R12 RES_K(10)
#define JR_R13 RES_K(47)
#define JR_R14 RES_K(30)
#define JR_R17 RES_K(47)
#define JR_R18 RES_K(100)
@ -645,6 +658,7 @@ DISCRETE_SOUND_END
#define JR_R27 RES_K(10)
#define JR_R28 RES_K(100)
#define JR_C13 CAP_U(4.7)
#define JR_C14 CAP_U(4.7)
#define JR_C15 CAP_U(22)
@ -656,6 +670,7 @@ DISCRETE_SOUND_END
#define JR_C21 CAP_N(56)
#define JR_C22 CAP_N(220)
#define JR_C23 CAP_U(0.47)
#define JR_C24 CAP_U(47)
#define JR_C25 CAP_U(1)
#define JR_C26 CAP_U(47)
#define JR_C27 CAP_U(22)
@ -687,15 +702,11 @@ static const discrete_mixer_desc dkongjr_mixer_desc =
{JR_R5, JR_R3, JR_R6, JR_R4, JR_R25},
{0,0,0,0,0}, // no variable resistors
{0,0,0,0,0}, // no node capacitors
0, RES_M(1), // Dummy,
0, 0,
JR_C155,
JR_C161,
0, 1};
#define JR_R12 RES_K(10)
#define JR_R13 RES_K(47)
#define JR_C24 CAP_U(47)
static const discrete_mixer_desc dkongjr_s1_mixer_desc =
{DISC_MIXER_IS_RESISTOR,
{JR_R13, JR_R12},
@ -866,12 +877,20 @@ static SOUND_RESET( dkong )
dkong_state *state = machine->driver_data;
state->mcustatus = 0;
state->page = 0;
state->page = 0x47;
state->portT = 0;
I8035_T_W_AL(0,0);
I8035_T_W_AL(1,0);
I8035_P1_W(255);
I8035_P2_W(255);
I8035_P1_W(0xFF);
I8035_P2_W(0xFF);
soundlatch_w(0,0x0F);
}
static SOUND_RESET( dkongjr )
{
sound_reset_dkong(machine);
soundlatch_w(0,0x00);
}
/****************************************************************
@ -1311,7 +1330,7 @@ MACHINE_DRIVER_START( dkongjr_audio )
MDRV_CPU_IO_MAP(dkongjr_sound_io_map, 0)
MDRV_SOUND_START(dkong)
MDRV_SOUND_RESET(dkong)
MDRV_SOUND_RESET(dkongjr)
MDRV_SPEAKER_STANDARD_MONO("mono")