mame/src/emu/machine/tmp68301.c
2015-05-21 20:06:05 +02:00

333 lines
7.9 KiB
C

// license:BSD-3-Clause
// copyright-holders:Luca Elia
/***************************************************************************
TMP68301 basic emulation + Interrupt Handling
The Toshiba TMP68301 is a 68HC000 + serial I/O, parallel I/O,
3 timers, address decoder, wait generator, interrupt controller,
all integrated in a single chip.
TODO:
- Interrupt generation: handle pending / in-service mechanisms
- Parallel port: handle timing latency
- Serial port: not done at all
- (and many other things)
***************************************************************************/
#include "emu.h"
#include "machine/tmp68301.h"
const device_type TMP68301 = &device_creator<tmp68301_device>;
static ADDRESS_MAP_START( tmp68301_regs, AS_0, 16, tmp68301_device )
// AM_RANGE(0x000,0x3ff) AM_RAM
AM_RANGE(0x094,0x095) AM_READWRITE(imr_r,imr_w)
AM_RANGE(0x098,0x099) AM_READWRITE(iisr_r,iisr_w)
/* Parallel Port */
AM_RANGE(0x100,0x101) AM_READWRITE(pdir_r,pdir_w)
AM_RANGE(0x10a,0x10b) AM_READWRITE(pdr_r,pdr_w)
/* Serial Port */
AM_RANGE(0x18e,0x18f) AM_READWRITE(scr_r,scr_w)
ADDRESS_MAP_END
// IRQ Mask register, 0x94
READ16_MEMBER(tmp68301_device::imr_r)
{
return m_imr;
}
WRITE16_MEMBER(tmp68301_device::imr_w)
{
COMBINE_DATA(&m_imr);
}
// IRQ In-Service Register
READ16_MEMBER(tmp68301_device::iisr_r)
{
return m_iisr;
}
WRITE16_MEMBER(tmp68301_device::iisr_w)
{
COMBINE_DATA(&m_iisr);
}
// Serial Control Register (TODO: 8-bit wide)
READ16_MEMBER(tmp68301_device::scr_r)
{
return m_scr;
}
WRITE16_MEMBER(tmp68301_device::scr_w)
{
/*
*--- ---- CKSE
--*- ---- RES
---- ---* INTM
*/
COMBINE_DATA(&m_scr);
m_scr &= 0xa1;
}
/* Parallel direction: 1 = output, 0 = input */
READ16_MEMBER(tmp68301_device::pdir_r)
{
return m_pdir;
}
WRITE16_MEMBER(tmp68301_device::pdir_w)
{
m_pdir = data;
}
READ16_MEMBER(tmp68301_device::pdr_r)
{
return m_in_parallel_cb(0) & ~m_pdir;
}
WRITE16_MEMBER(tmp68301_device::pdr_w)
{
m_out_parallel_cb(0, data & m_pdir, mem_mask);
}
tmp68301_device::tmp68301_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
: device_t(mconfig, TMP68301, "TMP68301", tag, owner, clock, "tmp68301", __FILE__),
device_memory_interface(mconfig, *this),
m_in_parallel_cb(*this),
m_out_parallel_cb(*this),
m_imr(0),
m_iisr(0),
m_scr(0),
m_pdir(0),
m_space_config("regs", ENDIANNESS_LITTLE, 16, 10, 0, NULL, *ADDRESS_MAP_NAME(tmp68301_regs))
{
memset(m_regs, 0, sizeof(m_regs));
memset(m_IE, 0, sizeof(m_IE));
memset(m_irq_vector, 0, sizeof(m_irq_vector));
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void tmp68301_device::device_start()
{
int i;
for (i = 0; i < 3; i++)
m_tmp68301_timer[i] = machine().scheduler().timer_alloc(timer_expired_delegate(FUNC(tmp68301_device::timer_callback), this));
m_in_parallel_cb.resolve_safe(0);
m_out_parallel_cb.resolve_safe();
save_item(NAME(m_regs));
save_item(NAME(m_IE));
save_item(NAME(m_irq_vector));
save_item(NAME(m_imr));
save_item(NAME(m_iisr));
save_item(NAME(m_scr));
save_item(NAME(m_pdir));
}
//-------------------------------------------------
// device_reset - device-specific reset
//-------------------------------------------------
void tmp68301_device::device_reset()
{
int i;
for (i = 0; i < 3; i++)
m_IE[i] = 0;
m_imr = 0x7f7; // mask all irqs
}
//-------------------------------------------------
// memory_space_config - return a description of
// any address spaces owned by this device
//-------------------------------------------------
const address_space_config *tmp68301_device::memory_space_config(address_spacenum spacenum) const
{
return (spacenum == AS_0) ? &m_space_config : NULL;
}
//**************************************************************************
// INLINE HELPERS
//**************************************************************************
//-------------------------------------------------
// read_byte - read a byte at the given address
//-------------------------------------------------
inline UINT16 tmp68301_device::read_word(offs_t address)
{
return space(AS_0).read_word(address << 1);
}
//-------------------------------------------------
// write_byte - write a byte at the given address
//-------------------------------------------------
inline void tmp68301_device::write_word(offs_t address, UINT16 data)
{
space(AS_0).write_word(address << 1, data);
}
IRQ_CALLBACK_MEMBER(tmp68301_device::irq_callback)
{
int vector = m_irq_vector[irqline];
// logerror("%s: irq callback returns %04X for level %x\n",machine.describe_context(),vector,int_level);
return vector;
}
TIMER_CALLBACK_MEMBER( tmp68301_device::timer_callback )
{
int i = param;
UINT16 TCR = m_regs[(0x200 + i * 0x20)/2];
UINT16 ICR = m_regs[0x8e/2+i]; // Interrupt Controller Register (ICR7..9)
UINT16 IVNR = m_regs[0x9a/2]; // Interrupt Vector Number Register (IVNR)
// logerror("s: callback timer %04X, j = %d\n",machine.describe_context(),i,tcount);
if ( (TCR & 0x0004) && // INT
!(m_imr & (0x100<<i))
)
{
int level = ICR & 0x0007;
// Interrupt Vector Number Register (IVNR)
m_irq_vector[level] = IVNR & 0x00e0;
m_irq_vector[level] += 4+i;
machine().firstcpu->set_input_line(level,HOLD_LINE);
}
if (TCR & 0x0080) // N/1
{
// Repeat
update_timer(i);
}
else
{
// One Shot
}
}
void tmp68301_device::update_timer( int i )
{
UINT16 TCR = m_regs[(0x200 + i * 0x20)/2];
UINT16 MAX1 = m_regs[(0x204 + i * 0x20)/2];
UINT16 MAX2 = m_regs[(0x206 + i * 0x20)/2];
int max = 0;
attotime duration = attotime::zero;
m_tmp68301_timer[i]->adjust(attotime::never,i);
// timers 1&2 only
switch( (TCR & 0x0030)>>4 ) // MR2..1
{
case 1:
max = MAX1;
break;
case 2:
max = MAX2;
break;
}
switch ( (TCR & 0xc000)>>14 ) // CK2..1
{
case 0: // System clock (CLK)
if (max)
{
int scale = (TCR & 0x3c00)>>10; // P4..1
if (scale > 8) scale = 8;
duration = attotime::from_hz(machine().firstcpu->unscaled_clock()) * ((1 << scale) * max);
}
break;
}
// logerror("%s: TMP68301 Timer %d, duration %lf, max %04X\n",machine().describe_context(),i,duration,max);
if (!(TCR & 0x0002)) // CS
{
if (duration != attotime::zero)
m_tmp68301_timer[i]->adjust(duration,i);
else
logerror("%s: TMP68301 error, timer %d duration is 0\n",machine().describe_context(),i);
}
}
/* Update the IRQ state based on all possible causes */
void tmp68301_device::update_irq_state()
{
int i;
/* Take care of external interrupts */
UINT16 IVNR = m_regs[0x9a/2]; // Interrupt Vector Number Register (IVNR)
for (i = 0; i < 3; i++)
{
if ( (m_IE[i]) &&
!(m_imr & (1<<i))
)
{
UINT16 ICR = m_regs[0x80/2+i]; // Interrupt Controller Register (ICR0..2)
// Interrupt Controller Register (ICR0..2)
int level = ICR & 0x0007;
// Interrupt Vector Number Register (IVNR)
m_irq_vector[level] = IVNR & 0x00e0;
m_irq_vector[level] += i;
m_IE[i] = 0; // Interrupts are edge triggerred
machine().firstcpu->set_input_line(level,HOLD_LINE);
}
}
}
READ16_MEMBER( tmp68301_device::regs_r )
{
return read_word(offset);
}
WRITE16_MEMBER( tmp68301_device::regs_w )
{
COMBINE_DATA(&m_regs[offset]);
write_word(offset,m_regs[offset]);
if (!ACCESSING_BITS_0_7) return;
// logerror("CPU #0 PC %06X: TMP68301 Reg %04X<-%04X & %04X\n",space.device().safe_pc(),offset*2,data,mem_mask^0xffff);
switch( offset * 2 )
{
// Timers
case 0x200:
case 0x220:
case 0x240:
{
int i = ((offset*2) >> 5) & 3;
update_timer( i );
}
break;
}
}
void tmp68301_device::external_interrupt_0() { m_IE[0] = 1; update_irq_state(); }
void tmp68301_device::external_interrupt_1() { m_IE[1] = 1; update_irq_state(); }
void tmp68301_device::external_interrupt_2() { m_IE[2] = 1; update_irq_state(); }