diff options
Diffstat (limited to 'src/mame/audio/timeplt.c')
-rw-r--r-- | src/mame/audio/timeplt.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/src/mame/audio/timeplt.c b/src/mame/audio/timeplt.c new file mode 100644 index 00000000000..32d4daa37ca --- /dev/null +++ b/src/mame/audio/timeplt.c @@ -0,0 +1,138 @@ +/*************************************************************************** + + This code is used by the following module: + + timeplt.c + pooyan.c + locomotn.c + tutankhm.c + rocnrope.c + +***************************************************************************/ + +#include "driver.h" +#include "sound/ay8910.h" +#include "sound/flt_rc.h" +#include "timeplt.h" + +static READ8_HANDLER( timeplt_portB_r ); +static WRITE8_HANDLER( timeplt_filter_w ); + +ADDRESS_MAP_START( timeplt_sound_readmem, ADDRESS_SPACE_PROGRAM, 8 ) + AM_RANGE(0x0000, 0x1fff) AM_READ(MRA8_ROM) + AM_RANGE(0x2000, 0x23ff) AM_READ(MRA8_RAM) + AM_RANGE(0x3000, 0x33ff) AM_READ(MRA8_RAM) + AM_RANGE(0x4000, 0x4000) AM_READ(AY8910_read_port_0_r) + AM_RANGE(0x6000, 0x6000) AM_READ(AY8910_read_port_1_r) +ADDRESS_MAP_END + +ADDRESS_MAP_START( timeplt_sound_writemem, ADDRESS_SPACE_PROGRAM, 8 ) + AM_RANGE(0x0000, 0x1fff) AM_WRITE(MWA8_ROM) + AM_RANGE(0x2000, 0x23ff) AM_WRITE(MWA8_RAM) + AM_RANGE(0x3000, 0x33ff) AM_WRITE(MWA8_RAM) + AM_RANGE(0x4000, 0x4000) AM_WRITE(AY8910_write_port_0_w) + AM_RANGE(0x5000, 0x5000) AM_WRITE(AY8910_control_port_0_w) + AM_RANGE(0x6000, 0x6000) AM_WRITE(AY8910_write_port_1_w) + AM_RANGE(0x7000, 0x7000) AM_WRITE(AY8910_control_port_1_w) + AM_RANGE(0x8000, 0x8fff) AM_WRITE(timeplt_filter_w) +ADDRESS_MAP_END + +ADDRESS_MAP_START( locomotn_sound_readmem, ADDRESS_SPACE_PROGRAM, 8 ) + AM_RANGE(0x0000, 0x1fff) AM_READ(MRA8_ROM) + AM_RANGE(0x2000, 0x23ff) AM_READ(MRA8_RAM) + AM_RANGE(0x4000, 0x4000) AM_READ(AY8910_read_port_0_r) + AM_RANGE(0x6000, 0x6000) AM_READ(AY8910_read_port_1_r) +ADDRESS_MAP_END + +ADDRESS_MAP_START( locomotn_sound_writemem, ADDRESS_SPACE_PROGRAM, 8 ) + AM_RANGE(0x0000, 0x1fff) AM_WRITE(MWA8_ROM) + AM_RANGE(0x2000, 0x23ff) AM_WRITE(MWA8_RAM) + AM_RANGE(0x3000, 0x3fff) AM_WRITE(timeplt_filter_w) + AM_RANGE(0x4000, 0x4000) AM_WRITE(AY8910_write_port_0_w) + AM_RANGE(0x5000, 0x5000) AM_WRITE(AY8910_control_port_0_w) + AM_RANGE(0x6000, 0x6000) AM_WRITE(AY8910_write_port_1_w) + AM_RANGE(0x7000, 0x7000) AM_WRITE(AY8910_control_port_1_w) +ADDRESS_MAP_END + + +struct AY8910interface timeplt_ay8910_interface = +{ + soundlatch_r, + timeplt_portB_r +}; + + +/* The timer clock which feeds the upper 4 bits of */ +/* AY-3-8910 port A is based on the same clock */ +/* feeding the sound CPU Z80. It is a divide by */ +/* 5120, formed by a standard divide by 512, */ +/* followed by a divide by 10 using a 4 bit */ +/* bi-quinary count sequence. (See LS90 data sheet */ +/* for an example). */ +/* */ +/* Bit 4 comes from the output of the divide by 1024 */ +/* 0, 1, 0, 1, 0, 1, 0, 1, 0, 1 */ +/* Bit 5 comes from the QC output of the LS90 producing a sequence of */ +/* 0, 0, 1, 1, 0, 0, 1, 1, 1, 0 */ +/* Bit 6 comes from the QD output of the LS90 producing a sequence of */ +/* 0, 0, 0, 0, 1, 0, 0, 0, 0, 1 */ +/* Bit 7 comes from the QA output of the LS90 producing a sequence of */ +/* 0, 0, 0, 0, 0, 1, 1, 1, 1, 1 */ + +static int timeplt_timer[10] = +{ + 0x00, 0x10, 0x20, 0x30, 0x40, 0x90, 0xa0, 0xb0, 0xa0, 0xd0 +}; + +static READ8_HANDLER( timeplt_portB_r ) +{ + /* need to protect from totalcycles overflow */ + static int last_totalcycles = 0; + + /* number of Z80 clock cycles to count */ + static int clock; + + int current_totalcycles; + + current_totalcycles = activecpu_gettotalcycles(); + clock = (clock + (current_totalcycles-last_totalcycles)) % 5120; + + last_totalcycles = current_totalcycles; + + return timeplt_timer[clock/512]; +} + + +static void filter_w(int chip, int channel, int data) +{ + int C = 0; + + if (data & 1) C += 220000; /* 220000pF = 0.220uF */ + if (data & 2) C += 47000; /* 47000pF = 0.047uF */ + filter_rc_set_RC(3*chip + channel,FLT_RC_LOWPASS, 1000,5100,0,CAP_P(C)); +} + +static WRITE8_HANDLER( timeplt_filter_w ) +{ + filter_w(0, 0, (offset >> 6) & 3); + filter_w(0, 1, (offset >> 8) & 3); + filter_w(0, 2, (offset >> 10) & 3); + filter_w(1, 0, (offset >> 0) & 3); + filter_w(1, 1, (offset >> 2) & 3); + filter_w(1, 2, (offset >> 4) & 3); +} + + +WRITE8_HANDLER( timeplt_sh_irqtrigger_w ) +{ + static int last; + + if (last == 0 && data) + { + /* setting bit 0 low then high triggers IRQ on the sound CPU */ + cpunum_set_input_line_and_vector(1,0,HOLD_LINE,0xff); + } + + last = data; +} + |