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/***************************************************************************

  ISA 8/16 bit Creative Labs Sound Blaster Sound Card

  TODO:
  - implement DAC
  - DSP type is a MCS-51 family, it has an internal ROM that needs decapping;
  - implement jumpers DIP-SWs;

***************************************************************************/

#include "emu.h"
#include "isa_sblaster.h"
#include "sound/speaker.h"
#include "sound/3812intf.h"
#include "sound/262intf.h"
#include "sound/saa1099.h"
#include "sound/dac.h"
#include "machine/pic8259.h"

/*
  adlib (YM3812/OPL2 chip), part of many many soundcards (soundblaster)
  soundblaster: YM3812 also accessible at 0x228/9 (address jumperable)
  soundblaster pro version 1: 2 YM3812 chips
   at 0x388 both accessed,
   at 0x220/1 left?, 0x222/3 right? (jumperable)
  soundblaster pro version 2: 1 OPL3 chip

  pro audio spectrum +: 2 OPL2
  pro audio spectrum 16: 1 OPL3

  2 x saa1099 chips
    also on sound blaster 1.0
    option on sound blaster 1.5

  jumperable? normally 0x220
*/
#define ym3812_StdClock XTAL_3_579545MHz
#define ymf262_StdClock XTAL_14_31818MHz

static const int m_cmd_fifo_length[256] =
{
/*   0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F        */
	-1, -1, -1, -1,  1,  3, -1, -1, -1, -1, -1,	-1, -1, -1,  2,  1, /* 0x */
	 2, -1, -1, -1,  3, -1,  3,  3, -1, -1, -1,	-1,  1, -1, -1,  1, /* 1x */
	-1, -1, -1, -1,  3, -1, -1, -1, -1, -1, -1,	-1, -1, -1, -1, -1, /* 2x */
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,	-1, -1, -1, -1, -1, /* 3x */
	 2,  3,  3, -1, -1, -1, -1, -1,  3, -1, -1,	-1, -1, -1, -1, -1, /* 4x */
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,	-1, -1, -1, -1, -1, /* 5x */
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,	-1, -1, -1, -1, -1, /* 6x */
	-1, -1, -1, -1,  3,  3,  3,  3, -1, -1, -1,	-1, -1,  1, -1,  1, /* 7x */
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,	-1, -1, -1, -1, -1, /* 8x */
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,	-1, -1, -1, -1, -1, /* 9x */
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,	-1, -1, -1, -1, -1, /* Ax */
	 4, -1, -1, -1, -1, -1,  4, -1,  4, -1, -1,	-1, -1, -1,  4, -1, /* Bx */
	 4, -1, -1, -1, -1, -1,  4, -1,  4, -1, -1,	-1, -1, -1,  4, -1, /* Cx */
	 1,  1, -1,  1, -1,  1,  1, -1,  1,  1,  1,	-1, -1, -1, -1, -1, /* Dx */
	 2,  1,  2,  1,  2, -1, -1, -1,  1, -1, -1,	-1, -1, -1, -1, -1, /* Ex */
	-1, -1,  1, -1, -1, -1, -1, -1,  1, -1, -1,	-1,  1, -1, -1, -1  /* Fx */
};

static const int protection_magic[4] = { 0x96, 0xa5, 0x69, 0x5a };

static const ym3812_interface pc_ym3812_interface =
{
	NULL
};

static const ymf262_interface pc_ymf262_interface =
{
	NULL
};

static MACHINE_CONFIG_FRAGMENT( sblaster1_0_config )
	MCFG_SPEAKER_STANDARD_STEREO("lspeaker", "rspeaker")
	MCFG_SOUND_ADD("ym3812", YM3812, ym3812_StdClock)
	MCFG_SOUND_CONFIG(pc_ym3812_interface)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", 3.00)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", 3.00)
	MCFG_SOUND_ADD("saa1099.1", SAA1099, 4772720)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", 0.50)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", 0.50)
	MCFG_SOUND_ADD("saa1099.2", SAA1099, 4772720)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", 0.50)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", 0.50)

	MCFG_SOUND_ADD("sbdacl", DAC, 0)
    MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", 1.00)
	MCFG_SOUND_ADD("sbdacr", DAC, 0)
    MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", 1.00)

	MCFG_PC_JOY_ADD("joy")
MACHINE_CONFIG_END

static MACHINE_CONFIG_FRAGMENT( sblaster1_5_config )
	MCFG_SPEAKER_STANDARD_STEREO("lspeaker", "rspeaker")
	MCFG_SOUND_ADD("ym3812", YM3812, ym3812_StdClock)
	MCFG_SOUND_CONFIG(pc_ym3812_interface)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", 1.00)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", 1.00)
	/* no CM/S support (empty sockets) */

	MCFG_SOUND_ADD("sbdacl", DAC, 0)
    MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", 1.00)
	MCFG_SOUND_ADD("sbdacr", DAC, 0)
    MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", 1.00)

	MCFG_PC_JOY_ADD("joy")
MACHINE_CONFIG_END

static MACHINE_CONFIG_FRAGMENT( sblaster_16_config )
	MCFG_SPEAKER_STANDARD_STEREO("lspeaker", "rspeaker")
	MCFG_SOUND_ADD("ymf262", YMF262, ymf262_StdClock)
	MCFG_SOUND_CONFIG(pc_ymf262_interface)
	MCFG_SOUND_ROUTE(0, "lspeaker", 1.00)
	MCFG_SOUND_ROUTE(1, "rspeaker", 1.00)
	MCFG_SOUND_ROUTE(2, "lspeaker", 1.00)
	MCFG_SOUND_ROUTE(3, "rspeaker", 1.00)
	MCFG_SOUND_ADD("sbdacl", DAC, 0)
    MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", 1.00)
	MCFG_SOUND_ADD("sbdacr", DAC, 0)
    MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", 1.00)

	MCFG_PC_JOY_ADD("joy")
MACHINE_CONFIG_END

static READ8_DEVICE_HANDLER( ym3812_16_r )
{
	UINT8 retVal = 0xff;
	switch(offset)
	{
		case 0 : retVal = ym3812_status_port_r( device, offset ); break;
	}
	return retVal;
}

static WRITE8_DEVICE_HANDLER( ym3812_16_w )
{
	switch(offset)
	{
		case 0 : ym3812_control_port_w( device, offset, data ); break;
		case 1 : ym3812_write_port_w( device, offset, data ); break;
	}
}

static READ8_DEVICE_HANDLER( saa1099_16_r )
{
	return 0xff;
}

static WRITE8_DEVICE_HANDLER( saa1099_16_w )
{
	switch(offset)
	{
		case 0 : saa1099_control_w( device, offset, data ); break;
		case 1 : saa1099_data_w( device, offset, data ); break;
	}
}

void sb_device::queue(UINT8 data)
{
	if (m_dsp.fifo_ptr < 15)
	{
		m_dsp.fifo[m_dsp.fifo_ptr] = data;

		m_dsp.fifo_ptr++;
	}
	else
	{
		// FIFO gets to la-la-land
		//logerror("FIFO?\n");
	}
}

void sb_device::queue_r(UINT8 data)
{
	m_dsp.rbuf_status |= 0x80;

	if (m_dsp.fifo_r_ptr < 52)
	{
		m_dsp.fifo_r[m_dsp.fifo_r_ptr] = data;

		m_dsp.fifo_r_ptr++;
	}
	else
	{
		// FIFO gets to la-la-land
		//logerror("FIFO?\n");
	}
}

UINT8 sb_device::dequeue_r()
{
	UINT8 data = m_dsp.fifo_r[0];

	if (m_dsp.fifo_r_ptr > 0)
	{
		for (int i = 0; i < 51; i++)
			m_dsp.fifo_r[i] = m_dsp.fifo_r[i + 1];

		m_dsp.fifo_r[51] = 0;

		m_dsp.fifo_r_ptr--;
	}

	if(m_dsp.fifo_r_ptr == 0)
		m_dsp.rbuf_status &= ~0x80;

	return data;
}


READ8_MEMBER( sb_device::dsp_reset_r )
{
//    printf("read DSP reset @ %x\n", offset);
	if(offset)
		return 0xff;
	logerror("Soundblaster DSP Reset port undocumented read\n");
	return 0xff;
}

WRITE8_MEMBER( sb_device::dsp_reset_w )
{
//    printf("%02x to DSP reset @ %x\n", data, offset);
	if(offset)
		return;

	if(data == 0 && m_dsp.reset_latch == 1)
	{
		// reset routine
		m_dsp.fifo_ptr = 0;
		m_dsp.fifo_r_ptr = 0;
		for(int i=0;i < 15; i++)
		{
			m_dsp.fifo[i] = 0;
			m_dsp.fifo_r[i] = 0;
		}
		queue_r(0xaa); // reset OK ID
	}

	m_dsp.reset_latch = data;
	drq_w(0);
	m_dsp.dma_autoinit = 0;
	irq_w(0, IRQ_ALL);
	m_timer->adjust(attotime::never, 0);
    m_dsp.d_rptr = 0;
    m_dsp.d_wptr = 0;
    m_dsp.dma_throttled = false;
    m_dsp.dma_timer_started = false;

	//printf("%02x\n",data);
}

READ8_MEMBER( sb_device::dsp_data_r )
{
//    printf("read DSP data @ %x\n", offset);
	if(offset)
		return 0xff;

	return dequeue_r();
}

WRITE8_MEMBER( sb_device::dsp_data_w )
{
//    printf("%02x to DSP data @ %x\n", data, offset);
	if(offset)
		return;
	logerror("Soundblaster DSP data port undocumented write\n");
}

READ8_MEMBER(sb_device::dsp_rbuf_status_r)
{
//    printf("read Rbufstat @ %x\n", offset);

    if(offset)
	{
		if(m_dsp.version > 0x0400)
			irq_w(0, IRQ_DMA16);
		return 0xff;
	}

//    printf("Clear IRQ5\n");
    irq_w(0, IRQ_DMA8);   // reading this port ACKs the card's IRQ, 8-bit dma only?

	return m_dsp.rbuf_status;
}

READ8_MEMBER(sb_device::dsp_wbuf_status_r)
{
//    printf("read Wbufstat @ %x\n", offset);
	if(offset)
		return 0xff;

	return m_dsp.wbuf_status;
}

WRITE8_MEMBER(sb_device::dsp_rbuf_status_w)
{
//    printf("%02x to Rbufstat @ %x\n", data, offset);
	if(offset)
		return;

	logerror("Soundblaster DSP Read Buffer status undocumented write\n");
}

void sb_device::process_fifo(UINT8 cmd)
{
	if (m_cmd_fifo_length[cmd] == -1)
	{
		logerror("SB: unemulated or undefined fifo command %02x\n",cmd);
		m_dsp.fifo_ptr = 0;
	}
	else if(m_dsp.fifo_ptr == m_cmd_fifo_length[cmd])
	{
		/* get FIFO params */
//        printf("SB FIFO command: %02x\n", cmd);
		switch(cmd)
		{
            case 0x10:  // Direct DAC
                break;

            case 0x14:  // 8-bit DMA, no autoinit
                m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
//                printf("Start DMA (not autoinit, size = %x)\n", m_dsp.dma_length);
                m_dsp.dma_transferred = 0;
                m_dsp.dma_autoinit = 0;
                m_dsp.dma_timer_started = false;
                m_dsp.dma_throttled = false;
                drq_w(1);
				m_dsp.flags = 0;
                break;

			case 0x17:  // 2-bit ADPCM w/new reference
				m_dsp.adpcm_new_ref = true;
				m_dsp.adpcm_step = 0;
			case 0x16:  // 2-bit ADPCM
				m_dsp.adpcm_count = 0;
				m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
				m_dsp.dma_transferred = 0;
				m_dsp.dma_autoinit = 0;
				m_dsp.dma_timer_started = false;
				m_dsp.dma_throttled = false;
				drq_w(1);
				m_dsp.flags = ADPCM2;
				break;

			case 0x1c:  // 8-bit DMA with autoinit
				//              printf("Start DMA (autoinit, size = %x)\n", m_dsp.dma_length);
				m_dsp.dma_transferred = 0;
				m_dsp.dma_autoinit = 1;
				m_dsp.dma_timer_started = false;
				m_dsp.dma_throttled = false;
				drq_w(1);
				m_dsp.flags = 0;
				break;

			case 0x24: // 8-bit ADC DMA
				m_dsp.adc_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
				//                printf("Start DMA (not autoinit, size = %x)\n", m_dsp.adc_length);
				m_dsp.adc_transferred = 0;
				m_dsp.dma_autoinit = 0;
				drq_w(1);
				logerror("SB: ADC capture unimplemented\n");
				break;

			case 0x40:  // set time constant
				m_dsp.frequency = (1000000 / (256 - m_dsp.fifo[1]));
				//printf("Set time constant: %02x -> %d\n", m_dsp.fifo[1], m_dsp.frequency);
				break;

			case 0x48:	// set DMA block size (for auto-init)
				m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
				break;

			case 0x75:  // 4-bit ADPCM w/new reference
				m_dsp.adpcm_new_ref = true;
				m_dsp.adpcm_step = 0;
			case 0x74:  // 4-bit ADPCM
				m_dsp.adpcm_count = 0;
				m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
				m_dsp.dma_transferred = 0;
				m_dsp.dma_autoinit = 0;
				m_dsp.dma_timer_started = false;
				m_dsp.dma_throttled = false;
				drq_w(1);
				m_dsp.flags = ADPCM4;
				break;

			case 0x77:  // 2.6-bit ADPCM w/new reference
				m_dsp.adpcm_new_ref = true;
				m_dsp.adpcm_step = 0;
			case 0x76:  // 2.6-bit ADPCM
				m_dsp.adpcm_count = 0;
				m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
				m_dsp.dma_transferred = 0;
				m_dsp.dma_autoinit = 0;
				m_dsp.dma_timer_started = false;
				m_dsp.dma_throttled = false;
				drq_w(1);
				m_dsp.flags = ADPCM3;
				break;

            case 0xd0:  // halt 8-bit DMA
                m_timer->adjust(attotime::never, 0);
                drq_w(0);   // drop DRQ
                m_dsp.dma_throttled = false;
                m_dsp.dma_timer_started = false;
                break;

            case 0xd1: // speaker on
				// ...
				m_dsp.speaker_on = 1;
				break;

			case 0xd3: // speaker off
				// ...
				m_dsp.speaker_on = 0;
				break;

			case 0xd8: // speaker status
				queue_r(m_dsp.speaker_on ? 0xff : 0x00);
				break;

			case 0xe0: // get DSP identification
				queue_r(m_dsp.fifo[1] ^ 0xff);
				break;

			case 0xe1: // get DSP version
				queue_r(m_dsp.version >> 8);
				queue_r(m_dsp.version & 0xff);
				break;

            case 0xe2: // DSP protection
                m_dsp.prot_value += protection_magic[m_dsp.prot_count++] ^ m_dsp.fifo[1];
                m_dsp.prot_count &= 3;
				m_dsp.adc_transferred = 0;
				m_dsp.adc_length = 1;
				m_dsp.wbuf_status = 0x80;
				m_dsp.dma_no_irq = true;
                m_dack_out = (UINT8)(m_dsp.prot_value & 0xff);
                drq_w(1);
                break;

			case 0xe4: // write test register
				m_dsp.test_reg = m_dsp.fifo[1];
				break;

			case 0xe8: // read test register
				queue_r(m_dsp.test_reg);
				break;

			case 0xf2: // send PIC irq
				irq_w(1, IRQ_DMA8);
				break;

			case 0xf8: // ???
				logerror("SB: Unknown command write 0xf8\n");
				queue_r(0);
				break;
			default:
				if(m_dsp.version >= 0x0201) // SB 2.0
				{
					switch(cmd)
					{
						case 0x1f:  // 2-bit autoinit ADPCM w/new reference
							m_dsp.adpcm_new_ref = true;
							m_dsp.adpcm_step = 0;
							m_dsp.adpcm_count = 0;
							m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
							m_dsp.dma_transferred = 0;
							m_dsp.dma_autoinit = 1;
							m_dsp.dma_timer_started = false;
							m_dsp.dma_throttled = false;
							drq_w(1);
							m_dsp.flags = ADPCM2;
							break;
						case 0x7d:  // 4-bit autoinit ADPCM w/new reference
							m_dsp.adpcm_new_ref = true;
							m_dsp.adpcm_step = 0;
							m_dsp.adpcm_count = 0;
							m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
							m_dsp.dma_transferred = 0;
							m_dsp.dma_autoinit = 1;
							m_dsp.dma_timer_started = false;
							m_dsp.dma_throttled = false;
							drq_w(1);
							m_dsp.flags = ADPCM4;
							break;
						case 0x7f:  // 2.6-bit autoinit ADPCM w/new reference
							m_dsp.adpcm_new_ref = true;
							m_dsp.adpcm_step = 0;
							m_dsp.adpcm_count = 0;
							m_dsp.dma_length = (m_dsp.fifo[1] + (m_dsp.fifo[2]<<8)) + 1;
							m_dsp.dma_transferred = 0;
							m_dsp.dma_autoinit = 1;
							m_dsp.dma_timer_started = false;
							m_dsp.dma_throttled = false;
							drq_w(1);
							m_dsp.flags = ADPCM3;
							break;
						case 0xda: // stop 8-bit autoinit
							m_dsp.dma_autoinit = 0;
							break;
					}
				}
				if(m_dsp.version >= 0x0301) // SB Pro 2
				{
					switch(cmd)
					{
						case 0xe3: // copyright notice, check if in pro 2
							const char* copyright = "NOT COPYRIGHT (C) CREATIVE TECHNOLOGY LTD, 1992.";
							int j = strlen(copyright);
							for(int k = 4; k <= j; k++)
								queue_r(copyright[k]);
							break;
					}
				}
				if(m_dsp.version >= 0x0400) // SB16
				{
					int mode;
					switch(cmd)
					{
						case 0x0f:  // read asp reg
							queue_r(0);
						case 0x0e:  // write asp reg
						case 0x02:  // get asp version
						case 0x04:  // set asp mode register
						case 0x05:  // set asp codec param
							logerror("SB16: unimplemented ASP command\n");
							break;
						case 0x41: // set output sample rate
							m_dsp.frequency = m_dsp.fifo[2] + (m_dsp.fifo[1] << 8);
							break;
						case 0x42: // set input sample rate
							m_dsp.adc_freq = m_dsp.fifo[2] + (m_dsp.fifo[1] << 8);
							break;
						case 0xd5: // pause 16-bit dma
							m_timer->adjust(attotime::never, 0);
							drq16_w(0);   // drop DRQ
							m_dsp.dma_throttled = false;
							m_dsp.dma_timer_started = false;
							break;
						case 0xd6: // resume 16-bit dma
							logerror("SB: 16-bit dma resume\n");
							break;
						case 0xd9: // stop 16-bit autoinit
							m_dsp.dma_autoinit = 0;
							break;
						case 0xb0:
						case 0xb6:
						case 0xc0:
						case 0xc6:
							mode = m_dsp.fifo[1];
							m_dsp.flags = 0;
							m_dsp.dma_length = (m_dsp.fifo[2] + (m_dsp.fifo[3]<<8)) + 1;
							if((cmd & 0xf0) == 0xb0)
							{
								m_dsp.flags |= SIXTEENBIT;
								m_dsp.dma_length <<= 1;
								drq16_w(1);
							}
							else
								drq_w(1);
							if(cmd & 0x04)
								m_dsp.dma_autoinit = 1;
							if(mode & 0x10)
								m_dsp.flags |= SIGNED;
							if(mode & 0x20)
							{
								m_dsp.flags |= STEREO;
								m_dsp.dma_length <<= 1;
							}
							m_dsp.dma_transferred = 0;
							m_dsp.dma_timer_started = false;
							m_dsp.dma_throttled = false;
							break;
						case 0xb8:
						case 0xbe:
						case 0xc8:
						case 0xce:
							mode = m_dsp.fifo[1];
							m_dsp.adc_length = (m_dsp.fifo[2] + (m_dsp.fifo[3]<<8)) + 1;
							m_dsp.adc_transferred = 0;
							if(cmd & 0x04)
								m_dsp.dma_autoinit = 1;
							if(mode & 0x20)
								m_dsp.adc_length <<= 1;
							if((cmd & 0xf0) == 0xb0)
							{
								m_dsp.adc_length <<= 1;
								drq16_w(1);
							}
							else
								drq_w(1);
							logerror("SB: ADC capture unimplemented\n");
							break;
						case 0xf3: // send PIC irq
							irq_w(1, IRQ_DMA16);
							break;
						case 0xfc:
							queue_r((((m_dsp.flags & SIXTEENBIT) && m_dsp.dma_autoinit) << 4) | ((!(m_dsp.flags & SIXTEENBIT) && m_dsp.dma_autoinit) << 2));
							break;
					}
				}
		}
		m_dsp.fifo_ptr = 0;
	}
}

WRITE8_MEMBER(sb_device::dsp_cmd_w)
{
//  printf("%02x to DSP command @ %x\n", data, offset);

    if(offset)
		return;

	queue(data);

	process_fifo(m_dsp.fifo[0]);
}

void sb_device::adpcm_decode(UINT8 sample, int size)
{
	const UINT8 adpcm_2_table[] =  {0, 1, 1, 3, 2, 6, 4, 12, 8, 24, 16, 48};
	const UINT8 step_2_table[] =   {0, 2, 0, 4, 2, 6, 4,  8, 6, 10,  8, 10};

	const UINT8 adpcm_3_table[] =  {0,  1,  2,  3,  1,  3,  5,  7,
									2,  6, 10, 14,  4, 12, 20, 28,
									8, 24, 40, 56};
	const UINT8 step_3_table[] =   {0,  0,  0,  4,  0,  4,  4,  8,
									4,  8,  8, 12,  8, 12, 12, 16,
									12, 16, 16, 16};

	const UINT8 adpcm_4_table[] =  {0,  1,  2,  3,  4,  5,  6,  7,
									1,  3,  5,  7,  9, 11, 13, 15,
									2,  6, 10, 14, 18, 22, 26, 30,
									4, 12, 20, 28, 36, 44, 52, 60};
	const UINT8 step_4_table[]  =  {0,  0,  0,  0,  0,  8,  8,  8,
									0,  8,  8,  8,  8, 16, 16, 16,
									8, 16, 16, 16, 16, 24, 24, 24,
									16, 24, 24, 24, 24, 24, 24, 24};

	INT16 dec_sample = m_dsp.adpcm_ref;
	UINT8 index;
	switch(size)
	{
		case 2:
			index = (sample & 1) | m_dsp.adpcm_step;
			dec_sample += ((sample & 2)?-1:1) * adpcm_2_table[index];
			m_dsp.adpcm_step = step_2_table[index];
			break;
		case 3:
			index = (sample & 3) | m_dsp.adpcm_step;
			dec_sample += ((sample & 4)?-1:1) * adpcm_3_table[index];
			m_dsp.adpcm_step = step_3_table[index];
			break;
		case 4:
			index = (sample & 7) | m_dsp.adpcm_step;
			dec_sample += ((sample & 8)?-1:1) * adpcm_4_table[index];
			m_dsp.adpcm_step = step_4_table[index];
			break;
	}

	if(dec_sample > 255)
		dec_sample = 255;
	else if(dec_sample < 0)
		dec_sample = 0;
	m_dsp.adpcm_ref = dec_sample;
	m_dacl->write_unsigned8(m_dsp.adpcm_ref);
	m_dacr->write_unsigned8(m_dsp.adpcm_ref);
}

READ8_MEMBER( sb16_device::mpu401_r )
{
	UINT8 res;

	irq_w(0, IRQ_MPU);
	if(offset == 0) // data
	{
		if(m_head != m_tail)
		{
			res = m_mpu_queue[m_tail++];
			m_tail %= 16;
		}
		else
			res = 0xff;
	}
	else // status
	{
		res = ((m_head != m_tail)?0:0x80) | 0x3f; // bit 7 queue empty (DSR), bit 6 DRR (Data Receive Ready?)
	}

	return res;
}

WRITE8_MEMBER( sb16_device::mpu401_w )
{
	if(offset == 0) // data
	{
		logerror("SB MPU401:%02x %02x\n",offset,data);
	}
	else // command
	{
		logerror("SB MPU401:%02x %02x\n",offset,data);

		switch(data)
		{
			case 0xff: // reset
				irq_w(1, IRQ_MPU);
				m_head = m_tail = 0;
				m_mpu_queue[m_head++] = 0xfe;
				break;
		}
	}

}

READ8_MEMBER( sb_device::mixer_r )
{
	if(offset == 0)
		return m_mixer_index;
	switch(m_mixer_index)
	{
		case 0: // reset
			return 0;
		default:
			if(m_dsp.version >= 0x0400)
			{
				switch(m_mixer_index)
				{
					case 0x82: // irqs
						return m_dsp.irq_active;
				}
			}
	}
	logerror("SB: Unimplemented read mixer command %02x\n", m_mixer_index);
	return 0;
}

WRITE8_MEMBER( sb_device::mixer_w )
{
	if(offset == 0)
	{
		m_mixer_index = data;
		return;
	}
	switch(m_mixer_index)
	{
		case 0: // reset
			return;
	}
	logerror("SB: Unimplemented write mixer command %02x\n", m_mixer_index);
	return;
}

//**************************************************************************
//  GLOBAL VARIABLES
//**************************************************************************

const device_type ISA8_SOUND_BLASTER_1_0 = &device_creator<isa8_sblaster1_0_device>;
const device_type ISA8_SOUND_BLASTER_1_5 = &device_creator<isa8_sblaster1_5_device>;
const device_type ISA16_SOUND_BLASTER_16 = &device_creator<isa16_sblaster16_device>;

//-------------------------------------------------
//  machine_config_additions - device-specific
//  machine configurations
//-------------------------------------------------

machine_config_constructor isa8_sblaster1_0_device::device_mconfig_additions() const
{
	return MACHINE_CONFIG_NAME( sblaster1_0_config );
}

machine_config_constructor isa8_sblaster1_5_device::device_mconfig_additions() const
{
	return MACHINE_CONFIG_NAME( sblaster1_5_config );
}

machine_config_constructor isa16_sblaster16_device::device_mconfig_additions() const
{
	return MACHINE_CONFIG_NAME( sblaster_16_config );
}

//**************************************************************************
//  LIVE DEVICE
//**************************************************************************

sb_device::sb_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, UINT32 clock, const char *name) :
    device_t(mconfig, type, name, tag, owner, clock),
    m_dacl(*this, "sbdacl"),
    m_dacr(*this, "sbdacr"),
	m_joy(*this, "joy")
{
}

sb8_device::sb8_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, UINT32 clock, const char *name) :
	sb_device(mconfig, type, tag, owner, clock, name),
    device_isa8_card_interface(mconfig, *this)
{
}

sb16_device::sb16_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, UINT32 clock, const char *name) :
	sb_device(mconfig, type, tag, owner, clock, name),
	device_isa16_card_interface(mconfig, *this)
{
}

//-------------------------------------------------
//  isa8_sblaster_device - constructor
//-------------------------------------------------

isa8_sblaster1_0_device::isa8_sblaster1_0_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
    sb8_device(mconfig, ISA8_SOUND_BLASTER_1_0, tag, owner, clock, "Sound Blaster 1.0")
{
}

isa8_sblaster1_5_device::isa8_sblaster1_5_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
    sb8_device(mconfig, ISA8_SOUND_BLASTER_1_5, tag, owner, clock, "Sound Blaster 1.5")
{
}

isa16_sblaster16_device::isa16_sblaster16_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
    sb16_device(mconfig, ISA16_SOUND_BLASTER_16, tag, owner, clock, "Sound Blaster 16")
{
}

//-------------------------------------------------
//  device_start - device-specific startup
//-------------------------------------------------

void sb8_device::device_start()
{
	m_isa->install_device(                   0x0200, 0x0207, 0, 0, read8_delegate(FUNC(pc_joy_device::joy_port_r), subdevice<pc_joy_device>("joy")), write8_delegate(FUNC(pc_joy_device::joy_port_w), subdevice<pc_joy_device>("joy")));
	m_isa->install_device(                   0x0226, 0x0227, 0, 0, read8_delegate(FUNC(sb_device::dsp_reset_r), this), write8_delegate(FUNC(sb_device::dsp_reset_w), this));
	m_isa->install_device(                   0x022a, 0x022b, 0, 0, read8_delegate(FUNC(sb_device::dsp_data_r), this), write8_delegate(FUNC(sb_device::dsp_data_w), this) );
	m_isa->install_device(                   0x022c, 0x022d, 0, 0, read8_delegate(FUNC(sb_device::dsp_wbuf_status_r), this), write8_delegate(FUNC(sb_device::dsp_cmd_w), this) );
	m_isa->install_device(                   0x022e, 0x022f, 0, 0, read8_delegate(FUNC(sb_device::dsp_rbuf_status_r), this), write8_delegate(FUNC(sb_device::dsp_rbuf_status_w), this) );
	if(m_dsp.version >= 0x0301)
	{
		m_isa->install_device(0x0224, 0x0225, 0, 0, read8_delegate(FUNC(sb_device::mixer_r), this), write8_delegate(FUNC(sb_device::mixer_w), this));
		m_isa->install_device(subdevice("ymf262"),    0x0388, 0x038b, 0, 0, FUNC(ymf262_r), FUNC(ymf262_w) );
		m_isa->install_device(subdevice("ymf262"),    0x0220, 0x0223, 0, 0, FUNC(ymf262_r), FUNC(ymf262_w) );
		m_isa->install_device(subdevice("ymf262"),    0x0228, 0x0229, 0, 0, FUNC(ymf262_r), FUNC(ymf262_w) );
	}
	else
	{
		m_isa->install_device(subdevice("ym3812"),    0x0388, 0x0389, 0, 0, FUNC(ym3812_16_r), FUNC(ym3812_16_w) );
		m_isa->install_device(subdevice("ym3812"),    0x0228, 0x0229, 0, 0, FUNC(ym3812_16_r), FUNC(ym3812_16_w) );
	}

    m_timer = timer_alloc(0, NULL);
}

void isa8_sblaster1_0_device::device_start()
{
    set_isa_device();
    // 1.0 always has the SAA1099s for CMS back-compatibility
	m_isa->install_device(subdevice("saa1099.1"), 0x0220, 0x0221, 0, 0, FUNC(saa1099_16_r), FUNC(saa1099_16_w) );
	m_isa->install_device(subdevice("saa1099.2"), 0x0222, 0x0223, 0, 0, FUNC(saa1099_16_r), FUNC(saa1099_16_w) );
	m_isa->set_dma_channel(1, this, FALSE);
	m_dsp.version = 0x0105;
    sb8_device::device_start();
}

void isa8_sblaster1_5_device::device_start()
{
    set_isa_device();
	/* 1.5 makes CM/S support optional (empty sockets, but they work if the user populates them!) */
	m_isa->set_dma_channel(1, this, FALSE);
	m_dsp.version = 0x0200;
    sb8_device::device_start();
}

void sb16_device::device_start()
{
	m_isa->install_device(                   0x0200, 0x0207, 0, 0, read8_delegate(FUNC(pc_joy_device::joy_port_r), subdevice<pc_joy_device>("joy")), write8_delegate(FUNC(pc_joy_device::joy_port_w), subdevice<pc_joy_device>("joy")));
	m_isa->install_device(                   0x0224, 0x0225, 0, 0, read8_delegate(FUNC(sb_device::mixer_r), this), write8_delegate(FUNC(sb_device::mixer_w), this));
	m_isa->install_device(                   0x0226, 0x0227, 0, 0, read8_delegate(FUNC(sb_device::dsp_reset_r), this), write8_delegate(FUNC(sb_device::dsp_reset_w), this));
	m_isa->install_device(                   0x022a, 0x022b, 0, 0, read8_delegate(FUNC(sb_device::dsp_data_r), this), write8_delegate(FUNC(sb_device::dsp_data_w), this) );
	m_isa->install_device(                   0x022c, 0x022d, 0, 0, read8_delegate(FUNC(sb_device::dsp_wbuf_status_r), this), write8_delegate(FUNC(sb_device::dsp_cmd_w), this) );
	m_isa->install_device(                   0x022e, 0x022f, 0, 0, read8_delegate(FUNC(sb_device::dsp_rbuf_status_r), this), write8_delegate(FUNC(sb_device::dsp_rbuf_status_w), this) );
	m_isa->install_device(                   0x0330, 0x0331, 0, 0, read8_delegate(FUNC(sb16_device::mpu401_r), this), write8_delegate(FUNC(sb16_device::mpu401_w), this));
	m_isa->install_device(subdevice("ymf262"),    0x0388, 0x038b, 0, 0, FUNC(ymf262_r), FUNC(ymf262_w) );
	m_isa->install_device(subdevice("ymf262"),    0x0220, 0x0223, 0, 0, FUNC(ymf262_r), FUNC(ymf262_w) );
	m_isa->install_device(subdevice("ymf262"),    0x0228, 0x0229, 0, 0, FUNC(ymf262_r), FUNC(ymf262_w) );

	m_head = 0;
	m_tail = 0;
	m_timer = timer_alloc(0, NULL);
}

void isa16_sblaster16_device::device_start()
{
	set_isa_device();
	m_isa->set_dma_channel(1, this, FALSE);
	m_isa->set_dma_channel(5, this, FALSE);
	m_dsp.version = 0x0405; // diagnose.exe rejects anything lower than 0x0402
    sb16_device::device_start();
}

//-------------------------------------------------
//  device_reset - device-specific reset
//-------------------------------------------------

void sb_device::device_reset()
{
    m_dsp.prot_value = 0xaa;
    m_dsp.prot_count = 0;
    m_dack_out = 0;
    m_dsp.fifo_ptr = 0;
    m_dsp.fifo_r_ptr = 0;
    m_dsp.wbuf_status = 0;
    m_dsp.rbuf_status = 0;
	m_dsp.frequency = 8000; // per stereo-fx
	m_dsp.irq_active = 0;
	m_mixer_index = 0;
	m_dsp.dma_no_irq = false;
}

UINT8 sb_device::dack_r(int line)
{
	m_dsp.adc_transferred++;
	if(m_dsp.adc_transferred >= m_dsp.adc_length)
	{
		drq_w(0);

		if (m_dsp.dma_autoinit)
		{
			m_dsp.adc_transferred = 0;
            drq_w(1);
		}
		else
			m_dsp.wbuf_status = 0;
		if(!m_dsp.dma_no_irq)
			irq_w(1, IRQ_DMA8);
		else
			m_dsp.dma_no_irq = false;
	}
	else
		drq_w(1);
    return m_dack_out;
}

UINT16 sb16_device::dack16_r(int line)
{
	m_dsp.adc_transferred += 2;
	if (m_dsp.adc_transferred >= m_dsp.adc_length)
    {
        drq16_w(0);

        if (m_dsp.dma_autoinit)
        {
            m_dsp.adc_transferred = 0;
			drq16_w(1);
        }
        irq_w(1, IRQ_DMA16);
	}
	else
		drq16_w(1);
	return m_dack_out;
}

void sb16_device::dack16_w(int line, UINT16 data)
{
    // set the transfer timer on the 1st byte
    if (!m_dsp.dma_timer_started)
    {
        m_timer->adjust(attotime::from_hz((double)m_dsp.frequency), 0, attotime::from_hz((double)m_dsp.frequency));
        m_dsp.d_rptr = m_dsp.d_wptr = 0;
        m_dsp.dma_timer_started = true;
    }

    m_dsp.data[m_dsp.d_wptr++] = data & 0xff;
    m_dsp.data[m_dsp.d_wptr++] = data >> 8;
    m_dsp.d_wptr %= 128;

    if (m_dsp.d_wptr == m_dsp.d_rptr)
    {
//        printf("throttling DRQ\n");
        drq16_w(0);	// drop DRQ here
        m_dsp.dma_throttled = true;
    }

    m_dsp.dma_transferred += 2;
    if (m_dsp.dma_transferred >= m_dsp.dma_length)
    {
//        printf("DMA fill completed (%d out of %d)\n", m_dsp.dma_transferred, m_dsp.dma_length);

        drq16_w(0);	// drop DRQ here

        if (m_dsp.dma_autoinit)
        {
//            printf("autoinit reset\n");
            m_dsp.dma_transferred = 0;
            if (!m_dsp.dma_throttled)   // if we're not throttled, re-raise DRQ right now
            {
                drq16_w(1);   // raise DRQ again (page 3-15 of the Creative manual indicates auto-init will keep going until you stop it)
            }
        }

        irq_w(1, IRQ_DMA16);	// raise IRQ as per the Creative manual
    }
}

/* TODO: this mustn't be instant! */
void sb_device::dack_w(int line, UINT8 data)
{
//    printf("dack_w: line %x data %02x\n", line, data);
//  if(data != 0x80)
//      printf("%02x\n",data);

    // set the transfer timer on the 1st byte
    if (!m_dsp.dma_timer_started)
    {
        m_timer->adjust(attotime::from_hz((double)m_dsp.frequency), 0, attotime::from_hz((double)m_dsp.frequency));
        m_dsp.d_rptr = m_dsp.d_wptr = 0;
        m_dsp.dma_timer_started = true;
    }

    m_dsp.data[m_dsp.d_wptr++] = data;
    m_dsp.d_wptr %= 128;

    if (m_dsp.d_wptr == m_dsp.d_rptr)
    {
//        printf("throttling DRQ\n");
        drq_w(0);	// drop DRQ here
        m_dsp.dma_throttled = true;
    }

    m_dsp.dma_transferred++;
    if (m_dsp.dma_transferred >= m_dsp.dma_length)
    {
//        printf("DMA fill completed (%d out of %d)\n", m_dsp.dma_transferred, m_dsp.dma_length);

        drq_w(0);	// drop DRQ here

        if (m_dsp.dma_autoinit)
        {
//            printf("autoinit reset\n");
            m_dsp.dma_transferred = 0;
            if (!m_dsp.dma_throttled)   // if we're not throttled, re-raise DRQ right now
            {
                drq_w(1);   // raise DRQ again (page 3-15 of the Creative manual indicates auto-init will keep going until you stop it)
            }
        }

        irq_w(1, IRQ_DMA8);	// raise IRQ as per the Creative manual
    }
}

void sb_device::device_timer(emu_timer &timer, device_timer_id tid, int param, void *ptr)
{
//    printf("DMA timer expire\n");

	UINT16 lsample, rsample;
	switch (m_dsp.flags) {
		case 0: // 8-bit unsigned mono
			m_dacl->write_unsigned8(m_dsp.data[m_dsp.d_rptr]);
			m_dacr->write_unsigned8(m_dsp.data[m_dsp.d_rptr]);
			m_dsp.data[m_dsp.d_rptr++] = 0x80;
			break;
		case SIGNED: // 8-bit signed mono
			m_dacl->write_unsigned8(m_dsp.data[m_dsp.d_rptr] + 128);
			m_dacr->write_unsigned8(m_dsp.data[m_dsp.d_rptr] + 128);
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			break;
		case STEREO: // 8-bit unsigned stereo
			m_dacl->write_unsigned8(m_dsp.data[m_dsp.d_rptr]);
		    m_dsp.data[m_dsp.d_rptr++] = 0x80;
			m_dacr->write_unsigned8(m_dsp.data[m_dsp.d_rptr]);
		    m_dsp.data[m_dsp.d_rptr++] = 0x80;
			break;
		case SIGNED | STEREO: // 8-bit signed stereo
			m_dacl->write_unsigned8(m_dsp.data[m_dsp.d_rptr] + 128);
		    m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dacr->write_unsigned8(m_dsp.data[m_dsp.d_rptr] + 128);
		    m_dsp.data[m_dsp.d_rptr++] = 0x00;
			break;
		case SIXTEENBIT: // 16-bit unsigned mono
			lsample = m_dsp.data[m_dsp.d_rptr] | (m_dsp.data[m_dsp.d_rptr+1] << 8);
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dsp.data[m_dsp.d_rptr++] = 0x80;
			m_dacl->write_unsigned16(lsample);
			m_dacr->write_unsigned16(lsample);
			break;
		case SIXTEENBIT | SIGNED: // 16-bit signed mono
			lsample = m_dsp.data[m_dsp.d_rptr] | (m_dsp.data[m_dsp.d_rptr+1] << 8);
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dacl->write_unsigned16(lsample + 32768);
			m_dacr->write_unsigned16(lsample + 32768);
			break;
		case SIXTEENBIT | STEREO: // 16-bit unsigned stereo
			lsample = m_dsp.data[m_dsp.d_rptr] | (m_dsp.data[m_dsp.d_rptr+1] << 8);
    		m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dsp.data[m_dsp.d_rptr++] = 0x80;
			m_dsp.d_rptr %= 128;
			rsample = m_dsp.data[m_dsp.d_rptr] | (m_dsp.data[m_dsp.d_rptr+1] << 8);
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dsp.data[m_dsp.d_rptr++] = 0x80;
			m_dacl->write_unsigned16(lsample);
			m_dacr->write_unsigned16(rsample);
			break;
		case SIXTEENBIT | SIGNED | STEREO: // 16-bit signed stereo
			lsample = m_dsp.data[m_dsp.d_rptr] | (m_dsp.data[m_dsp.d_rptr+1] << 8);
    		m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dsp.d_rptr %= 128;
			rsample = m_dsp.data[m_dsp.d_rptr] | (m_dsp.data[m_dsp.d_rptr+1] << 8);
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dsp.data[m_dsp.d_rptr++] = 0x00;
			m_dacl->write_unsigned16(lsample + 32768);
			m_dacr->write_unsigned16(rsample + 32768);
			break;
		case ADPCM2:
			if(m_dsp.adpcm_new_ref)
			{
				m_dsp.adpcm_ref = m_dsp.data[m_dsp.d_rptr++];
				m_dsp.adpcm_new_ref = false;
				m_dacl->write_unsigned8(m_dsp.adpcm_ref);
				m_dacr->write_unsigned8(m_dsp.adpcm_ref);
				break;
			}
			lsample = m_dsp.data[m_dsp.d_rptr];
			switch(m_dsp.adpcm_count++)
			{
				case 0:
					adpcm_decode(lsample >> 6, 2);
					break;
				case 1:
					adpcm_decode((lsample >> 4) & 3, 2);
					break;
				case 2:
					adpcm_decode((lsample >> 2) & 3, 2);
					break;
				case 3:
					adpcm_decode(lsample & 3, 2);
					m_dsp.data[m_dsp.d_rptr++] = 0x80;
					m_dsp.adpcm_count = 0;
					break;
			}
			break;
		case ADPCM3:
			if(m_dsp.adpcm_new_ref)
			{
				m_dsp.adpcm_ref = m_dsp.data[m_dsp.d_rptr++];
				m_dsp.adpcm_new_ref = false;
				m_dacl->write_unsigned8(m_dsp.adpcm_ref);
				m_dacr->write_unsigned8(m_dsp.adpcm_ref);
				break;
			}
			lsample = m_dsp.data[m_dsp.d_rptr];
			switch(m_dsp.adpcm_count++)
			{
				case 0:
					adpcm_decode(lsample >> 5, 3);
					break;
				case 1:
					adpcm_decode((lsample >> 2) & 7, 3);
					break;
				case 2:
					adpcm_decode(((lsample & 2) << 1) | (lsample & 1), 3);
					m_dsp.data[m_dsp.d_rptr++] = 0x80;
					m_dsp.adpcm_count = 0;
					break;
			}
			break;
		case ADPCM4:
			if(m_dsp.adpcm_new_ref)
			{
				m_dsp.adpcm_ref = m_dsp.data[m_dsp.d_rptr++];
				m_dsp.adpcm_new_ref = false;
				m_dacl->write_unsigned8(m_dsp.adpcm_ref);
				m_dacr->write_unsigned8(m_dsp.adpcm_ref);
				break;
			}
			lsample = m_dsp.data[m_dsp.d_rptr];
			switch(m_dsp.adpcm_count++)
			{
				case 0:
					adpcm_decode(lsample >> 4, 4);
					break;
				case 1:
					adpcm_decode(lsample & 15, 4);
					m_dsp.data[m_dsp.d_rptr++] = 0x80;
					m_dsp.adpcm_count = 0;
					break;
			}
			break;
		default:
			logerror("SB: unimplemented sample type %x\n", m_dsp.flags);
	}
    m_dsp.d_rptr %= 128;

    if (m_dsp.dma_throttled)
    {
        if (m_dsp.d_rptr == m_dsp.d_wptr)
        {
//            printf("unthrottling DRQ\n");
            if(m_dsp.flags & SIXTEENBIT) // 16-bit audio through 8-bit dma?
				drq16_w(1);
			else
				drq_w(1);   // raise DRQ
            m_dsp.dma_throttled = false;
        }
    }
}