public void write(short addr, short data)
{
if (addr > 0x0f)
{
return;
}
regs[addr] = data;
if (locked)
{
return; // Stop program changing time interval
}
// Sync up timer
long cycles;
cycles = m_eventContext.getTime(m_accessClk, m_phase);
m_accessClk += cycles;
ta -= (int)cycles;
if (ta == 0)
{
_event();
}
switch (addr)
{
case 0x4:
ta_latch = SIDEndian.endian_16lo8(ta_latch, data);
break;
case 0x5:
ta_latch = SIDEndian.endian_16hi8(ta_latch, data);
if ((cra & 0x01) == 0) // Reload timer if stopped
{
ta = ta_latch;
}
break;
case 0x0e:
cra = (short)(data | 0x01);
if ((data & 0x10) != 0)
{
cra &= (~0x10 & 0xff);
ta = ta_latch;
}
m_eventContext.schedule(m_taEvent, (long)ta + 1, m_phase);
break;
default:
break;
}
}
public override short read(short addr)
{
long cycles = m_context.getTime(m_accessClk, m_phase);
// > not for debug
m_accessClk += cycles;
if (m_optimisation != 0)
{
if (cycles != 0)
{
m_sid.clock((int)cycles);
}
}
else
{
while ((cycles--) != 0)
{
m_sid.clock();
}
}
// <
return((short)m_sid.read(addr));
}
public override void _event()
{
long cycles = event_context.getTime(m_rasterClk, event_context.phase);
// Cycle already executed check
if (cycles == 0)
{
return;
}
long delay = 1;
int cycle;
// Update x raster
m_rasterClk += cycles;
raster_x += (int)cycles;
cycle = (raster_x + 9) % xrasters;
raster_x %= xrasters;
switch (cycle)
{
case 0:
{
// Calculate sprite DMA
short y = (short)(raster_y & 0xff);
short mask = 1;
sprite_expand_y ^= regs[0x17];
for (int i = 1; i < 0x10; i += 2, mask <<= 1)
{
if (((regs[0x15] & mask) != 0) && (y == regs[i]))
{
sprite_dma |= mask;
sprite_mc_base[i >> 1] = 0;
sprite_expand_y &= (short)(~(regs[0x17] & mask) & 0xff);
}
}
delay = 2;
if ((sprite_dma & 0x01) != 0)
{
addrctrl(false);
}
else
{
addrctrl(true);
// No sprites before next compulsory cycle
if ((sprite_dma & 0x1f) == 0)
{
delay = 9;
}
}
break;
}
case 1:
break;
case 2:
if ((sprite_dma & 0x02) != 0)
{
addrctrl(false);
}
break;
case 3:
if ((sprite_dma & 0x03) == 0)
{
addrctrl(true);
}
break;
case 4:
if ((sprite_dma & 0x04) != 0)
{
addrctrl(false);
}
break;
case 5:
if ((sprite_dma & 0x06) == 0)
{
addrctrl(true);
}
break;
case 6:
if ((sprite_dma & 0x08) != 0)
{
addrctrl(false);
}
break;
case 7:
if ((sprite_dma & 0x0c) == 0)
{
addrctrl(true);
}
break;
case 8:
if ((sprite_dma & 0x10) != 0)
{
addrctrl(false);
}
break;
case 9: // IRQ occurred (xraster != 0)
if (raster_y == (yrasters - 1))
{
vblanking = true;
}
else
{
raster_y++;
// Trigger raster IRQ if IRQ line reached
if (raster_y == raster_irq)
{
trigger(MOS656X_INTERRUPT_RST);
}
}
if ((sprite_dma & 0x18) == 0)
{
addrctrl(true);
}
break;
case 10: // Vertical blank (line 0)
if (vblanking)
{
vblanking = lp_triggered = false;
raster_y = 0;
// Trigger raster IRQ if IRQ in line 0
if (raster_irq == 0)
{
trigger(MOS656X_INTERRUPT_RST);
}
}
if ((sprite_dma & 0x20) != 0)
{
addrctrl(false);
}
// No sprites before next compulsory cycle
else if ((sprite_dma & 0xf8) == 0)
{
delay = 10;
}
break;
case 11:
if ((sprite_dma & 0x30) == 0)
{
addrctrl(true);
}
break;
case 12:
if ((sprite_dma & 0x40) != 0)
{
addrctrl(false);
}
break;
case 13:
if ((sprite_dma & 0x60) == 0)
{
addrctrl(true);
}
break;
case 14:
if ((sprite_dma & 0x80) != 0)
{
addrctrl(false);
}
break;
case 15:
delay = 2;
if ((sprite_dma & 0xc0) == 0)
{
addrctrl(true);
delay = 5;
}
break;
case 16:
break;
case 17:
delay = 2;
if ((sprite_dma & 0x80) == 0)
{
addrctrl(true);
delay = 3;
}
break;
case 18:
break;
case 19:
addrctrl(true);
break;
case 20: // Start bad line
{
// In line $30, the DEN bit controls if Bad Lines can occur
if (raster_y == first_dma_line)
{
bad_lines_enabled = (ctrl1 & 0x10) != 0;
}
// Test for bad line condition
bad_line = (raster_y >= first_dma_line) && (raster_y <= last_dma_line) && ((raster_y & 7) == y_scroll) && bad_lines_enabled;
if (bad_line)
{
// DMA starts on cycle 23
addrctrl(false);
}
delay = 3;
break;
}
case 23:
{
for (int i = 0; i < sprite_mc_base.Length; i++) //for (int i = 0; i < 8; i++)
{
if ((sprite_expand_y & (1 << i)) != 0)
{
sprite_mc_base[i] += 2;
}
}
break;
}
case 24:
{
short mask = 1;
for (int i = 0; i < sprite_mc_base.Length; i++, mask <<= 1) //for (int i = 0; i < 8; i++, mask <<= 1)
{
if ((sprite_expand_y & mask) != 0)
{
sprite_mc_base[i]++;
}
if ((sprite_mc_base[i] & 0x3f) == 0x3f)
{
sprite_dma &= (short)(~mask & 0xff);
}
}
delay = 39;
break;
}
case 63: // End DMA - Only get here for non PAL
addrctrl(true);
delay = xrasters - cycle;
break;
default:
if (cycle < 23)
{
delay = 23 - cycle;
}
else if (cycle < 63)
{
delay = 63 - cycle;
}
else
{
delay = xrasters - cycle;
}
break;
}
event_context.schedule(this, delay - (event_context.phase == event_phase_t.EVENT_CLOCK_PHI1 ? 0 : 1), m_phase);
}
internal void ta_event()
{
// Timer Modes
long cycles;
short mode = (short)(cra & 0x21);
if (mode == 0x21)
{
if ((ta--) != 0)
{
return;
}
}
cycles = event_context.getTime(m_accessClk, m_phase);
m_accessClk += cycles;
ta = ta_latch;
ta_underflow ^= true; // toggle flipflop
if ((cra & 0x08) != 0)
{
// one shot, stop timer A
cra &= (~0x01 & 0xff);
}
else if (mode == 0x01)
{
// Reset event
event_context.schedule(event_ta, (long)ta + 1, m_phase);
}
trigger(INTERRUPT_TA);
// Handle serial port
if ((cra & 0x40) != 0)
{
if (sdr_count != 0)
{
if ((--sdr_count) == 0)
{
trigger(INTERRUPT_SP);
}
}
if ((sdr_count == 0) && sdr_buffered)
{
sdr_out = regs[SDR];
sdr_buffered = false;
sdr_count = 16; // Output rate 8 bits at ta / 2
}
}
switch (crb & 0x61)
{
case 0x01:
tb -= (int)cycles;
break;
case 0x41:
case 0x61:
tb_event();
break;
}
}