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psr60: Figured out more YM2154 including start/end and more realistic timer computations

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This commit is contained in:
Aaron Giles 2021-05-27 09:07:50 -07:00
parent b9a8f82133
commit 0c415fa923
1 changed files with 30 additions and 18 deletions
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48
src/mame/drivers/ympsr60.cpp
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@ -122,6 +122,7 @@ private:
u8 ym2154_r(offs_t offset);
void ym2154_w(offs_t offset, u8 data);
attotime ym2154_period(u32 tempo) const { return attotime::from_hz(2250000 / 12 / 8) * (2048 - tempo); }
public:
INPUT_CHANGED_MEMBER(drvif_changed);
@ -140,10 +141,19 @@ void psr60_state::psr60_map(address_map &map)
//
// YM2154 - ROMpler with I/O ports
//
// Chip is clocked at 2.25MHz
//
// Some of this looks suspiciously like 2x the ADPCM-A attached to the
// YM2608: 6 channels (x2), total level and instrument levels behave
// YM2608: 6 channels (2 banks), total level and instrument levels behave
// the same.
//
// Start/end addresses are 9 bits to address 32k ROMs (15 bits) so
// presume a left shift of 6 (actually 7 if 4-bit ADPCM data).
//
// Two serial ROMs are connected, containing 32k of sample data each.
// It appears that the channel bank (0-5 vs 6-11) implies which of the
// two ROMs is read.
//
// System-wide registers:
// 01 -------- Unknown ($00 written at init)
// 02 1xxxxxxx Timer upper bits latch
@ -151,22 +161,24 @@ void psr60_state::psr60_map(address_map &map)
// 03 -x------ Unknown (IRQ enable?)
// -----x-- Timer enable
// 04 --xxxxxx Master volume (0=min, 3F=max)
// 05 --xxxxxx Channels 6-11 key on/off
// 06 --xxxxxx Channels 0-5 key on/off
// 05 --xxxxxx Bank 2 key on/off
// 06 --xxxxxx Bank 1 key on/off
// 07 -------x Unknown ($01 written at init)
//
// Per-channel registers (channel in address bits 0-2)
// 08-0D -------- Unknown (written after others; ch 0-5 overlaps 6-11 here)
// 10-15 ---xxxxx Ch 0-5 Instrument volume (0=min, 1F=max)
// 18-1D ---xxxxx Ch 6-11 Instrument volume (0=min, 1F=max)
// 20-25 ---xxxxx Ch 0-5 Start address?
// 28-2D xx------ Ch 0-5 ???
// -------x Ch 0-5 ???
// 30-35 xxxxxxx Ch 0-5 ???
// 38-3D ---xxxxx Ch 6-11 Start address?
// 40-45 xx------ Ch 6-11 ???
// -------x Ch 6-11 ???
// 48-4D xxxxxxx Ch 6-11 ???
// 08-0D -------- Unknown; written as two nibbles so shared between banks
// 10-15 -xx----- Bank 1 Write 11 here to disable?
// ---xxxxx Bank 1 Instrument volume (0=min, 1F=max)
// 18-1D -xx----- Bank 2 Write 11 here to disable?
// ---xxxxx Bank 2 Instrument volume (0=min, 1F=max)
// 20-25 ---xxxxx Bank 1 Start address upper bits
// 28-2D xxxx---- Bank 1 Start address lower bits
// -------x Bank 1 End address upper bits
// 30-35 xxxxxxxx Bank 1 End address lower bits
// 38-3D ---xxxxx Bank 2 Start address upper bits
// 40-45 xxxx---- Bank 2 Start address lower bits
// -------x Bank 2 End address upper bits
// 48-4D xxxxxxxx Bank 2 End address lower bits
//
// Reads:
// 01-0A xxxxxxxx AN1-10 digital values
@ -217,7 +229,7 @@ void psr60_state::ym2154_w(offs_t offset, u8 data)
if (BIT(old ^ data, 2) != 0)
{
if (BIT(data, 2) != 0)
m_ym2154_timer->adjust(attotime::from_msec(512 * 1024) / m_ym2154_tempo);
m_ym2154_timer->adjust(ym2154_period(m_ym2154_tempo));
else
m_ym2154_timer->enable(false);
}
@ -233,13 +245,13 @@ void psr60_state::ym2154_w(offs_t offset, u8 data)
{
for (int bit = 0; bit < 6; bit++)
if (BIT(data, bit) != 0)
printf("YM2154: Ch%2d on: %02X %02X %02X vol=%02X low=%02X\n", 6 + bit, m_ym2154_regs[0x38+bit], m_ym2154_regs[0x40+bit], m_ym2154_regs[0x48+bit], m_ym2154_regs[0x18+bit], m_ym2154_regs[0x08+bit]);
printf("YM2154: Bank 2 Ch %d on: %03X-%03X vol=%02X low=%X\n", bit, (m_ym2154_regs[0x38+bit] << 4) | (m_ym2154_regs[0x40+bit] >> 4), ((m_ym2154_regs[0x40+bit] & 0x0f) << 8) | m_ym2154_regs[0x48+bit], m_ym2154_regs[0x18+bit], m_ym2154_regs[0x08+bit] >> 4);
}
else if (offset == 6)
{
for (int bit = 0; bit < 6; bit++)
if (BIT(data, bit) != 0)
printf("YM2154: Ch%2d on: %02X %02X %02X vol=%02X low=%02X\n", bit, m_ym2154_regs[0x20+bit], m_ym2154_regs[0x28+bit], m_ym2154_regs[0x30+bit], m_ym2154_regs[0x10+bit], m_ym2154_regs[0x08+bit]);
printf("YM2154: Bank 1 Ch %d on: %03X-%03X vol=%02X low=%X\n", bit, (m_ym2154_regs[0x20+bit] << 4) | (m_ym2154_regs[0x28+bit] >> 4), ((m_ym2154_regs[0x28+bit] & 0x0f) << 8) | m_ym2154_regs[0x30+bit], m_ym2154_regs[0x10+bit], m_ym2154_regs[0x08+bit] & 0xf);
}
else if (offset < 8 || offset >= 0x50)
printf("YM2154: Write %02X = %02X\n", offset, data);
@ -250,7 +262,7 @@ TIMER_CALLBACK_MEMBER(psr60_state::ym2154_timer)
m_ym2154_irq = 1;
recalc_irqs();
if (BIT(m_ym2154_regs[3], 2) != 0)
m_ym2154_timer->adjust(attotime::from_msec(512 * 1024 / 16) / m_ym2154_tempo);
m_ym2154_timer->adjust(ym2154_period(m_ym2154_tempo));
}
INPUT_CHANGED_MEMBER(psr60_state::ryp4_changed)