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-rw-r--r--src/devices/sound/roland_lp.cpp381
1 files changed, 381 insertions, 0 deletions
diff --git a/src/devices/sound/roland_lp.cpp b/src/devices/sound/roland_lp.cpp
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+++ b/src/devices/sound/roland_lp.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Valley Bell
+
+// register write:
+// 00/01 - ??
+// 02/03 - ROM bank (bits 10-13) / loop mode (bits 14-15)
+// 04/05 - frequency (2.14 fixed point, 0x4000 = 32000 Hz)
+// 06/07 - volume
+// 08/09 - sample start address, fraction (2.14 fixed point, i.e. 1 byte = 0x4000)
+// 0A/0B - sample start address (high word, i.e. address bits 2..17)
+// 0C/0D - sample end address (high word)
+// 0E/0F - sample loop address (high word)
+// 10/12 - ?? (sometimes value 1F is written)
+// 11/13/15/17 - voice enable mask (11 = least significant 8 bits, 17 = most significant 8 bits)
+// 19/1B/1D - ?? (written at init time)
+// 1A - ??
+// 1F - voice select
+//
+// register read:
+// 01 - last sample data (used by main CPU to read sample table from PCM ROM)
+// 02/03 - ?? (read after writing to 10/12)
+
+#include "emu.h"
+#include "roland_lp.h"
+
+
+DEFINE_DEVICE_TYPE(MB87419_MB87420, mb87419_mb87420_device, "mb87419_mb87420", "Roland LP MB87419/MB87420 PCM")
+
+mb87419_mb87420_device::mb87419_mb87420_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+ : device_t(mconfig, MB87419_MB87420, tag, owner, clock)
+ , device_sound_interface(mconfig, *this)
+ , device_rom_interface(mconfig, *this)
+ , m_int_callback(*this)
+ , m_clock(0)
+ , m_rate(0)
+ , m_stream(nullptr)
+ , m_sel_chn(0)
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void mb87419_mb87420_device::device_start()
+{
+ m_clock = clock() / 2;
+ m_rate = m_clock / 512; // usually 32 KHz
+
+ m_stream = stream_alloc(0, 2, m_rate);
+
+ logerror("Roland PCM: Clock %u, Rate %u\n", m_clock, m_rate);
+}
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void mb87419_mb87420_device::device_reset()
+{
+ m_int_callback(CLEAR_LINE);
+}
+
+//-------------------------------------------------
+// rom_bank_pre_change - refresh the stream if the
+// ROM banking changes
+//-------------------------------------------------
+
+void mb87419_mb87420_device::rom_bank_pre_change()
+{
+ // unused right now
+ m_stream->update();
+}
+
+
+u8 mb87419_mb87420_device::read(offs_t offset)
+{
+ // Note: only offset 0x01 is verified, the rest is probably all wrong
+ if (offset != 0x01)
+ logerror("Reading Reg %02X\n", offset);
+ if (offset < 0x10)
+ {
+ pcm_channel& chn = m_chns[m_sel_chn];
+ switch(offset)
+ {
+ case 0x00:
+ return (chn.mode >> 0) & 0xFF;
+ case 0x01:
+ m_stream->update();
+ {
+ offs_t addr = (chn.addr >> 14) | ((chn.bank & 0x3C00) << 8);
+ return read_byte(addr); // return sample data
+ }
+ case 0x02: // ROM bank LSB
+ return (chn.bank >> 0) & 0xFF;
+ case 0x03: // ROM bank MSB
+ return (chn.bank >> 8) & 0xFF;
+ case 0x04: // sample step LSB
+ return (chn.step >> 0) & 0xFF;
+ case 0x05: // sample step LSB
+ return (chn.step >> 8) & 0xFF;
+ case 0x06: // volume LSB
+ return (chn.volume >> 0) & 0xFF;
+ case 0x07: // volume MSB
+ return (chn.volume >> 8) & 0xFF;
+ case 0x08: // current address, fraction LSB
+ return (chn.start >> 0) & 0xFF;
+ case 0x09: // current address, fraction MSB
+ return (chn.start >> 8) & 0xFF;
+ case 0x0A: // current address LSB
+ return (chn.start >> 16) & 0xFF;
+ case 0x0B: // current address MSB
+ return (chn.start >> 24) & 0xFF;
+ case 0x0C: // sample end address LSB
+ return (chn.end >> 0) & 0xFF;
+ case 0x0D: // sample end address MSB
+ return (chn.end >> 8) & 0xFF;
+ case 0x0E: // sample loop address LSB
+ return (chn.loop >> 0) & 0xFF;
+ case 0x0F: // sample loop address MSB
+ return (chn.loop >> 8) & 0xFF;
+ }
+ }
+ else
+ {
+ switch(offset)
+ {
+ case 0x11:
+ case 0x13:
+ case 0x15:
+ case 0x17:
+ m_stream->update();
+ {
+ uint8_t basechn = ((offset >> 1) & 0x03) * 8;
+ uint8_t result = 0x00;
+ for (uint8_t ch_id = 0; ch_id < 8; ch_id ++)
+ result |= (m_chns[basechn + ch_id].enable << ch_id);
+ return result;
+ }
+ break;
+ case 0x1F:
+ return m_sel_chn;
+ }
+ }
+ return 0x00;
+}
+
+void mb87419_mb87420_device::write(offs_t offset, u8 data)
+{
+ logerror("Reg %02X = %02X\n", offset, data);
+ if (offset < 0x10)
+ {
+ pcm_channel& chn = m_chns[m_sel_chn];
+ switch(offset)
+ {
+ case 0x00:
+ chn.mode = (chn.mode & 0xFF00) | (data << 0);
+ break;
+ case 0x01:
+ chn.mode = (chn.mode & 0x00FF) | (data << 8);
+ break;
+ case 0x02: // ROM bank LSB
+ chn.bank = (chn.bank & 0xFF00) | (data << 0);
+ break;
+ case 0x03: // ROM bank MSB / loop mode
+ chn.bank = (chn.bank & 0x00FF) | (data << 8);
+ break;
+ case 0x04: // sample step LSB
+ chn.step = (chn.step & 0xFF00) | (data << 0);
+ break;
+ case 0x05: // sample step LSB
+ chn.step = (chn.step & 0x00FF) | (data << 8);
+ break;
+ case 0x06: // volume LSB
+ chn.volume = (chn.volume & 0xFF00) | (data << 0);
+ break;
+ case 0x07: // volume MSB
+ chn.volume = (chn.volume & 0x00FF) | (data << 8);
+ break;
+ case 0x08: // current address, fraction LSB
+ chn.start = (chn.start & 0xFFFFFF00) | (data << 0);
+ if (chn.enable)
+ logerror("Roland PCM, channel %u: changing start address while playing!\n", m_sel_chn);
+ break;
+ case 0x09: // current address, fraction MSB
+ chn.start = (chn.start & 0xFFFF00FF) | (data << 8);
+ if (chn.enable)
+ logerror("Roland PCM, channel %u: changing start address while playing!\n", m_sel_chn);
+ break;
+ case 0x0A: // current address LSB
+ chn.start = (chn.start & 0xFF00FFFF) | (data << 16);
+ if (chn.enable)
+ logerror("Roland PCM, channel %u: changing start address while playing!\n", m_sel_chn);
+ break;
+ case 0x0B: // current address MSB
+ chn.start = (chn.start & 0x00FFFFFF) | (data << 24);
+ if (chn.enable)
+ logerror("Roland PCM, channel %u: changing start address while playing!\n", m_sel_chn);
+ break;
+ case 0x0C: // sample end address, LSB
+ chn.end = (chn.end & 0xFF00) | (data << 0);
+ break;
+ case 0x0D: // sample end address MSB
+ chn.end = (chn.end & 0x00FF) | (data << 8);
+ break;
+ case 0x0E: // sample loop address LSB
+ chn.loop = (chn.loop & 0xFF00) | (data << 0);
+ break;
+ case 0x0F: // sample loop address MSB
+ chn.loop = (chn.loop & 0x00FF) | (data << 8);
+ break;
+ }
+ }
+ else
+ {
+ switch(offset)
+ {
+ case 0x11:
+ case 0x13:
+ case 0x15:
+ case 0x17:
+ {
+ uint8_t basechn = ((offset >> 1) & 0x03) * 8;
+ for (uint8_t ch_id = 0; ch_id < 8; ch_id ++)
+ {
+ pcm_channel& chn = m_chns[basechn + ch_id];
+ bool play = static_cast<bool>((data >> ch_id) & 1);
+
+ if (play && ! chn.enable)
+ {
+ chn.addr = chn.start;
+ offs_t addr = (chn.addr >> 14) | ((chn.bank & 0x3C00) << 8);
+ chn.smpl_cur = 0;
+ chn.smpl_nxt = decode_sample((int8_t)read_byte(addr));
+ chn.play_dir = +1;
+ logerror("Starting channel %u, bank 0x%04X, addr 0x%05X.%03X\n",
+ basechn + ch_id, chn.bank, chn.start >> 14, (chn.start & 0x3FFF) << 2);
+ logerror("Smpl End Ofs: 0x%04X, Loop Ofs 0x%04X, Step 0x%04X, Volume %04X\n",
+ chn.end << 2, chn.loop << 2, chn.step, chn.volume);
+ }
+ chn.enable = play;
+ }
+ }
+ break;
+ case 0x1F:
+ m_sel_chn = data & 0x1F;
+ break;
+ default:
+ logerror("Writing unknown reg %02X = %02X\n", offset, data);
+ break;
+ }
+ }
+}
+
+//-------------------------------------------------
+// sound_stream_update - handle a stream update
+//-------------------------------------------------
+
+void mb87419_mb87420_device::sound_stream_update(sound_stream &stream)
+{
+ for (auto& chn : m_chns)
+ {
+ if (! chn.enable || chn.play_dir == 0)
+ continue;
+
+ for (int smpl = 0; smpl < stream.samples(); smpl ++)
+ {
+ s32 smp_data;
+ if (chn.play_dir > 0)
+ smp_data = sample_interpolate(chn.smpl_cur, chn.smpl_nxt, chn.addr & 0x3FFF);
+ else
+ smp_data = sample_interpolate(chn.smpl_nxt, chn.smpl_cur, chn.addr & 0x3FFF);
+ smp_data = smp_data * chn.volume;
+ stream.add_int(0, smpl, smp_data, 32768 << 14); // >>14 results in a good overall volume
+ stream.add_int(1, smpl, smp_data, 32768 << 14);
+
+ uint32_t old_addr = chn.addr;
+ if (chn.play_dir > 0)
+ chn.addr += chn.step;
+ else if (chn.play_dir < 0)
+ chn.addr -= chn.step;
+
+ // Note: The sample data is read after incrementing the address, but before handling loop points.
+ // Reading the sample data after loop point handling breaks the test mode square wave.
+ // (Sample 0xA7 on the CM-32P.)
+ if ((chn.addr >> 14) != (old_addr >> 14))
+ {
+ offs_t addr = (chn.addr >> 14) | ((chn.bank & 0x3C00) << 8);
+ //logerror("Chn %u: sample addr 0x%05X.%03X\n", &chn - &m_chns[0], chn.addr >> 14, (chn.addr & 0x3FFF) << 2);
+ chn.smpl_cur = chn.smpl_nxt;
+ chn.smpl_nxt += decode_sample((int8_t)read_byte(addr)); // This was verified to be independent from play_dir.
+
+ // until the decoding is fixed, we prevent overflow bugs (due to DC offsets when looping) this way
+ chn.smpl_nxt = std::clamp<int16_t>(chn.smpl_nxt, -0x7FF, +0x7FF);
+ }
+
+ bool reachedEnd = false;
+ if (chn.play_dir > 0)
+ {
+ // This works well with the test mode sine/square wave samples.
+ if ((chn.addr >> 16) >= chn.end)
+ reachedEnd = true;
+ }
+ else if (chn.play_dir < 0)
+ {
+ if ((chn.addr >> 16) < chn.loop)
+ reachedEnd = true;
+ }
+ if (reachedEnd)
+ {
+ offs_t oldAddr = chn.addr;
+ logerror("Chn %u: Sample End at addr 0x%05X.%03X. (Dir %d, Loop Mode %u)\n",
+ &chn - &m_chns[0], chn.addr >> 14, (chn.addr & 0x3FFF) << 2,
+ chn.play_dir, chn.bank >> 14);
+ switch(chn.bank >> 14)
+ {
+ case 0: // normal loop
+ chn.addr = chn.addr + ((chn.loop - chn.end) << 16);
+ logerror("addr 0x%05X.%03X -> addr 0x%05X.%03X\n",
+ oldAddr >> 14, (oldAddr & 0x3FFF) << 2,
+ chn.addr >> 14, (chn.addr & 0x3FFF) << 2);
+ break;
+ case 1: // no loop
+ case 3: // invalid, assume "no loop"
+ chn.play_dir = 0;
+ break;
+ case 2: // ping-pong
+ // CM-32P samples with ping-pong loop mode:
+ // 0x00 (low piano note), 0x58..0x67, 0x69..0x6C (choir/strings), 0x9F..0xA4 (brass)
+ // Note: These formulae are probably incorrect, as they cause some DC offset in most samples.
+ // Reference sample rate for C5 @ Sample 9F: 34290 Hz.
+ if (chn.play_dir > 0)
+ chn.addr = (chn.end << 16) - chn.addr + (chn.end << 16);
+ else if (chn.play_dir < 0)
+ chn.addr = (chn.loop << 16) - chn.addr + (chn.loop << 16);
+ chn.play_dir = -chn.play_dir;
+ break;
+ }
+ if (chn.play_dir == 0)
+ break;
+ }
+ }
+ }
+
+ return;
+}
+
+int16_t mb87419_mb87420_device::decode_sample(int8_t data)
+{
+ int16_t val;
+ int16_t sign;
+ uint8_t shift;
+ int16_t result;
+
+ if (data < 0)
+ {
+ sign = -1;
+ val = -data;
+ }
+ else
+ {
+ sign = +1;
+ val = data;
+ }
+
+ // thanks to Sarayan for figuring out the decoding formula
+ shift = val >> 4;
+ val &= 0x0F;
+ if (! shift)
+ result = val;
+ else
+ result = (0x10 + val) << (shift - 1);
+ return result * sign;
+}
+
+int16_t mb87419_mb87420_device::sample_interpolate(int16_t smp1, int16_t smp2, uint16_t frac)
+{
+ int32_t smpfrac0 = (int32_t)smp1 * (0x4000 - frac);
+ int32_t smpfrac1 = (int32_t)smp2 * frac;
+ return (int16_t)((smpfrac0 + smpfrac1) >> 14);
+}