static READ16_HANDLER( pitfighb_cheap_slapstic_r )
{
int result = bslapstic_base[offset & 0xfff];
/* the cheap replacement slapstic just triggers on the simple banking */
/* addresses; a software patch ensure that this is good enough */
/* offset 0 primes the chip */
if (offset == 0)
bslapstic_primed = 1;
/* one of 4 bankswitchers produces the result */
else if (bslapstic_primed)
{
if (offset == 0x42)
update_bank(0), bslapstic_primed = 0;
else if (offset == 0x52)
update_bank(1), bslapstic_primed = 0;
else if (offset == 0x62)
update_bank(2), bslapstic_primed = 0;
else if (offset == 0x72)
update_bank(3), bslapstic_primed = 0;
}
return result;
}
void sam6883_device::configure_bank(int bank, UINT8 *memory, UINT32 memory_size, bool is_read_only, read8_delegate rhandler, write8_delegate whandler)
{
assert((bank >= 0) && (bank < sizeof(m_banks) / sizeof(m_banks[0])));
m_banks[bank].m_memory = memory;
m_banks[bank].m_memory_size = memory_size;
m_banks[bank].m_memory_read_only = is_read_only;
m_banks[bank].m_rhandler = rhandler;
m_banks[bank].m_whandler = whandler;
/* if we're configuring a bank that never changes, update it now */
switch(bank)
{
case 4:
update_bank(4, 0xFF00, 0xFF1F, 0x0000);
break;
case 5:
update_bank(5, 0xFF20, 0xFF3F, 0x0000);
break;
case 6:
update_bank(6, 0xFF40, 0xFF5F, 0x0000);
break;
case 7:
update_bank(7, 0xFF60, 0xFFBF, 0x0000);
break;
case 2:
update_bank(2, 0xFFE0, 0xFFFF, 0x1FE0);
break;
}
}
void sam6883_device::set_bank_offset(int bank, offs_t offset)
{
if (m_banks[bank].m_memory_offset != offset)
{
m_banks[bank].m_memory_offset = offset;
update_memory();
update_bank(2, 0xFFE0, 0xFFFF, 0x1FE0);
}
}
void sam6883_device::update_memory(void)
{
/* Memory size - allowed restricting memory accesses to something less than
* 32k
*
* This was a SAM switch that occupied 4 addresses:
*
* $FFDD (set) R1
* $FFDC (clear) R1
* $FFDB (set) R0
* $FFDA (clear) R0
*
* R1:R0 formed the following states:
* 00 - 4k
* 01 - 16k
* 10 - 64k
* 11 - static RAM (??)
*
* If something less than 64k was set, the low RAM would be smaller and
* mirror the other parts of the RAM
*
* TODO: Find out what "static RAM" is
* TODO: This should affect _all_ memory accesses, not just video ram
* TODO: Verify that the CoCo 3 ignored this
*/
/* update $0000-$7FFF */
update_bank(0, 0x0000, 0x7FFF, m_sam_state & SAM_STATE_P1 ? 0x8000 : 0x0000);
if (m_sam_state & SAM_STATE_TY)
{
update_bank(0, 0x8000, 0xFEFF, 0x8000);
}
else
{
update_bank(1, 0x8000, 0x9FFF, 0x0000);
update_bank(2, 0xA000, 0xBFFF, 0x0000);
update_bank(3, 0xC000, 0xFEFF, 0x0000);
}
}
void MEMORY::reset()
{
// reset crtc
lcdadr = 0;
memset(lcdreg, 0, sizeof(lcdreg));
dcr1 = dcr2 = 0;
kj_l = kj_h = kj_ofs = kj_row = 0;
blinkcnt = 0;
// reset memory
mcr1 = 2;
mcr2 = a20 = 0;
update_bank();
}
void MEMORY::write_io8(uint32 addr, uint32 data)
{
switch(addr & 0xffff) {
// memory controller
case 0x1d:
mcr1 = data;
update_bank();
// protect mode ???
// d_cpu->write_signal(SIG_I86_A20, data, 0x10);
break;
case 0x1e:
mcr2 = data;
update_bank();
break;
case 0x26:
a20 = data;
// protect mode ???
d_cpu->write_signal(SIG_I86_A20, data, 0x80);
break;
// dma bank
case 0x120:
case 0x121:
case 0x122:
case 0x123:
d_dma->write_signal(SIG_I8237_BANK0 + (addr & 3), data, 0x0f);
break;
// lcd controller
case 0x300:
lcdadr = data;
break;
case 0x302:
lcdreg[lcdadr & 31] = data;
break;
case 0x308:
dcr1 = (dcr1 & 0xff00) | data;
break;
case 0x309:
dcr1 = (dcr1 & 0xff) | (data << 8);
// bit11-10: vram bank
update_bank();
break;
case 0x30a:
dcr1 = (dcr1 & 0xff00) | data;
break;
case 0x30b:
dcr1 = (dcr1 & 0xff) | (data << 8);
break;
// kanji rom
case 0x30c:
kj_h = data & 0x7f;
break;
case 0x30d:
kj_l = data & 0x7f;
kj_row = 0;
if(kj_h < 0x30) {
kj_ofs = (((kj_l - 0x00) & 0x1f) << 5) | (((kj_l - 0x20) & 0x20) << 9) | (((kj_l - 0x20) & 0x40) << 7) | (((kj_h - 0x00) & 0x07) << 10);
}
else if(kj_h < 0x70) {
kj_ofs = (((kj_l - 0x00) & 0x1f) << 5) + (((kj_l - 0x20) & 0x60) << 9) + (((kj_h - 0x00) & 0x0f) << 10) + (((kj_h - 0x30) & 0x70) * 0xc00) + 0x08000;
}
else {
kj_ofs = (((kj_l - 0x00) & 0x1f) << 5) | (((kj_l - 0x20) & 0x20) << 9) | (((kj_l - 0x20) & 0x40) << 7) | (((kj_h - 0x00) & 0x07) << 10) | 0x38000;
}
break;
case 0x30e:
kanji16[(kj_ofs | ((kj_row & 0x0f) << 1)) & 0x3ffff] = data;
break;
case 0x30f:
kanji16[(kj_ofs | ((kj_row++ & 0x0f) << 1) | 1) & 0x3ffff] = data;
break;
}
}