void nes_exrom_device::update_prg()
{
int bank0, bank1, bank2, bank3;
switch (m_prg_mode)
{
case 0: // 32k banks
bank3 = m_prg_regs[3] >> 2;
prg32(bank3);
break;
case 1: // 16k banks
bank1 = m_prg_regs[1] >> 1;
bank3 = m_prg_regs[3] >> 1;
if (m_prg_ram_mapped[1])
{
prgram_bank8_x(0, ((bank1 << 1) & 0x07));
prgram_bank8_x(1, ((bank1 << 1) & 0x07) | 1);
}
else
prg16_89ab(bank1);
prg16_cdef(bank3);
break;
case 2: // 16k-8k banks
bank1 = m_prg_regs[1] >> 1;
bank2 = m_prg_regs[2];
bank3 = m_prg_regs[3];
if (m_prg_ram_mapped[1])
{
prgram_bank8_x(0, ((bank1 << 1) & 0x07));
prgram_bank8_x(1, ((bank1 << 1) & 0x07) | 1);
}
else
prg16_89ab(bank1);
if (m_prg_ram_mapped[2])
prgram_bank8_x(2, bank2 & 0x07);
else
prg8_cd(bank2);
prg8_ef(bank3);
break;
case 3: // 8k banks
bank0 = m_prg_regs[0];
bank1 = m_prg_regs[1];
bank2 = m_prg_regs[2];
bank3 = m_prg_regs[3];
if (m_prg_ram_mapped[0])
prgram_bank8_x(0, bank0 & 0x07);
else
prg8_89(bank0);
if (m_prg_ram_mapped[1])
prgram_bank8_x(1, bank1 & 0x07);
else
prg8_ab(bank1);
if (m_prg_ram_mapped[2])
prgram_bank8_x(2, bank2 & 0x07);
else
prg8_cd(bank2);
prg8_ef(bank3);
break;
}
}
void nes_exrom_device::update_prg()
{
int bank0, bank1, bank2, bank3;
switch (m_prg_mode)
{
case 0: // 32k banks
bank3 = m_prg_regs[3];
prg32(bank3 >> 2);
break;
case 1: // 16k banks
bank1 = m_prg_regs[1];
bank3 = m_prg_regs[3];
if (!BIT(bank1, 7)) // PRG RAM
{
prgram_bank8_x(0, (bank1 & 0x06));
prgram_bank8_x(1, (bank1 & 0x06) + 1);
}
else
prg16_89ab(bank1 >> 1);
prg16_cdef(bank3);
break;
case 2: // 16k-8k banks
bank1 = m_prg_regs[1];
bank2 = m_prg_regs[2];
bank3 = m_prg_regs[3];
if (!BIT(bank1, 7))
{
prgram_bank8_x(0, (bank1 & 0x06));
prgram_bank8_x(1, (bank1 & 0x06) + 1);
}
else
prg16_89ab((bank1 & 0x7f) >> 1);
if (!BIT(bank2, 7))
prgram_bank8_x(2, bank2 & 0x07);
else
prg8_cd(bank2 & 0x7f);
prg8_ef(bank3);
break;
case 3: // 8k banks
bank0 = m_prg_regs[0];
bank1 = m_prg_regs[1];
bank2 = m_prg_regs[2];
bank3 = m_prg_regs[3];
if (!BIT(bank0, 7))
prgram_bank8_x(0, bank0 & 0x07);
else
prg8_89(bank0 & 0x7f);
if (!BIT(bank1, 7))
prgram_bank8_x(1, bank1 & 0x07);
else
prg8_ab(bank1 & 0x7f);
if (!BIT(bank2, 7))
prgram_bank8_x(2, bank2 & 0x07);
else
prg8_cd(bank2 & 0x7f);
prg8_ef(bank3);
break;
}
}
