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-rw-r--r--src/devices/machine/applepic.cpp406
1 files changed, 406 insertions, 0 deletions
diff --git a/src/devices/machine/applepic.cpp b/src/devices/machine/applepic.cpp
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+++ b/src/devices/machine/applepic.cpp
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+// license:BSD-3-Clause
+// copyright-holders:AJR
+/**********************************************************************
+
+ Apple Computer 343S1021 PIC (Peripheral Interface Controller)
+
+ NCR standard cell ASIC, 65CX02 CPU core
+
+**********************************************************************/
+
+#include "emu.h"
+#include "applepic.h"
+
+// device type definition
+DEFINE_DEVICE_TYPE(APPLEPIC, applepic_device, "applepic", "Apple 343S1021 PIC")
+
+const std::string_view applepic_device::s_interrupt_names[8] = { "0", "DMA 1", "DMA 2", "peripheral", "host", "timer", "6", "7" };
+
+applepic_device::applepic_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+ : device_t(mconfig, APPLEPIC, tag, owner, clock)
+ , m_iopcpu(*this, "iopcpu")
+ , m_prd_callback(*this)
+ , m_pwr_callback(*this)
+ , m_hint_callback(*this)
+ , m_gpout_callback(*this)
+ , m_ram_address(0)
+ , m_status_reg(0x80)
+ , m_timer_counter(0)
+ , m_timer_latch(0)
+ , m_scc_control(0)
+ , m_io_control(0)
+ , m_timer_dpll_control(0)
+ , m_int_mask(0)
+ , m_int_reg(0)
+{
+ for (dma_channel &channel : m_dma_channel)
+ {
+ channel.control = 0;
+ channel.map = 0;
+ channel.tc = 0;
+ }
+}
+
+void applepic_device::internal_map(address_map &map)
+{
+ map(0x0000, 0x6fff).mirror(0x8000).ram();
+ map(0x7000, 0x77ff).ram();
+ map(0x7800, 0x7fff).mirror(0x8000).ram();
+ map(0xf010, 0xf013).rw(FUNC(applepic_device::timer_r), FUNC(applepic_device::timer_w));
+ map(0xf020, 0xf02f).rw(FUNC(applepic_device::dma_channel_r), FUNC(applepic_device::dma_channel_w));
+ map(0xf030, 0xf030).rw(FUNC(applepic_device::scc_control_r), FUNC(applepic_device::scc_control_w));
+ map(0xf031, 0xf031).rw(FUNC(applepic_device::io_control_r), FUNC(applepic_device::io_control_w));
+ map(0xf032, 0xf032).rw(FUNC(applepic_device::timer_dpll_control_r), FUNC(applepic_device::timer_dpll_control_w));
+ map(0xf033, 0xf033).rw(FUNC(applepic_device::int_mask_r), FUNC(applepic_device::int_mask_w));
+ map(0xf034, 0xf034).rw(FUNC(applepic_device::int_reg_r), FUNC(applepic_device::int_reg_w));
+ map(0xf035, 0xf035).rw(FUNC(applepic_device::host_reg_r), FUNC(applepic_device::host_reg_w));
+ map(0xf040, 0xf04f).rw(FUNC(applepic_device::device_reg_r), FUNC(applepic_device::device_reg_w));
+}
+
+void applepic_device::device_add_mconfig(machine_config &config)
+{
+ R65C02(config, m_iopcpu, DERIVED_CLOCK(1, 8));
+ m_iopcpu->set_addrmap(AS_PROGRAM, &applepic_device::internal_map);
+}
+
+void applepic_device::device_resolve_objects()
+{
+ // Resolve callbacks
+ m_prd_callback.resolve_safe(0);
+ m_pwr_callback.resolve_safe();
+ m_hint_callback.resolve_safe();
+ m_gpout_callback.resolve_all_safe();
+}
+
+void applepic_device::device_start()
+{
+ // Save internal state
+ save_item(NAME(m_ram_address));
+ save_item(NAME(m_status_reg));
+ save_item(NAME(m_timer_counter));
+ save_item(NAME(m_timer_latch));
+ save_item(STRUCT_MEMBER(m_dma_channel, control));
+ save_item(STRUCT_MEMBER(m_dma_channel, map));
+ save_item(STRUCT_MEMBER(m_dma_channel, tc));
+ save_item(NAME(m_scc_control));
+ save_item(NAME(m_io_control));
+ save_item(NAME(m_timer_dpll_control));
+ save_item(NAME(m_int_mask));
+ save_item(NAME(m_int_reg));
+}
+
+void applepic_device::device_reset()
+{
+ m_status_reg &= 0xc3;
+ m_int_mask = 0;
+
+ m_iopcpu->set_input_line(INPUT_LINE_RESET, ASSERT_LINE);
+ m_iopcpu->set_input_line(r65c02_device::IRQ_LINE, CLEAR_LINE);
+ m_hint_callback(CLEAR_LINE);
+}
+
+u8 applepic_device::host_r(offs_t offset)
+{
+ if (BIT(offset, 4))
+ {
+ if (BIT(m_scc_control, 0))
+ return m_prd_callback(offset & 0x0f);
+ else
+ {
+ if (!machine().side_effects_disabled())
+ logerror("%s: Read from device register $%X in non-bypass mode\n", machine().describe_context(), offset & 0x0f);
+ return 0;
+ }
+ }
+ else if (BIT(offset, 2))
+ {
+ // Shared RAM read access
+ u8 data = m_iopcpu->space(AS_PROGRAM).read_byte(m_ram_address);
+ if (BIT(m_status_reg, 1) && !machine().side_effects_disabled())
+ ++m_ram_address;
+ return data;
+ }
+ else if (BIT(offset, 1))
+ {
+ // PINT (D6) and /REQ (D7) are used in bypass mode only
+ return BIT(m_scc_control, 0) ? m_status_reg | 0x01 : (m_status_reg & 0x3f) | 0x80;
+ }
+ else if (BIT(offset, 0))
+ return m_ram_address & 0x00ff;
+ else
+ return (m_ram_address & 0xff00) >> 8;
+}
+
+void applepic_device::host_w(offs_t offset, u8 data)
+{
+ if (BIT(offset, 4))
+ {
+ if (BIT(m_scc_control, 0))
+ m_pwr_callback(offset & 0x0f, data);
+ else
+ logerror("%s: Write $%02X to device register $%X in non-bypass mode\n", machine().describe_context(), data, offset & 0x0f);
+ }
+ else if (BIT(offset, 2))
+ {
+ // Shared RAM write access
+ m_iopcpu->space(AS_PROGRAM).write_byte(m_ram_address, data);
+ if (BIT(m_status_reg, 1))
+ ++m_ram_address;
+ }
+ else if (BIT(offset, 1))
+ {
+ if (BIT(m_status_reg, 2) != BIT(data, 2))
+ {
+ logerror("%s: /RSTPIC %dactive\n", machine().describe_context(), BIT(data, 2) ? "in" : "");
+ m_iopcpu->set_input_line(INPUT_LINE_RESET, BIT(data, 2) ? CLEAR_LINE : ASSERT_LINE);
+ }
+ if (BIT(data, 3))
+ set_interrupt(4);
+ if ((m_status_reg & data & 0x30) != 0)
+ {
+ m_status_reg &= ~(data & 0x30);
+ if ((m_status_reg & 0x30) == 0)
+ {
+ logerror("%s: Host interrupts acknowledged\n", machine().describe_context());
+ m_hint_callback(CLEAR_LINE);
+ }
+ }
+ m_status_reg = (data & 0x06) | (m_status_reg & 0xf0);
+ }
+ else if (BIT(offset, 0))
+ m_ram_address = (m_ram_address & 0xff00) | data;
+ else
+ m_ram_address = u16(data) << 8 | (m_ram_address & 0x00ff);
+}
+
+WRITE_LINE_MEMBER(applepic_device::pint_w)
+{
+ if (state == ASSERT_LINE)
+ {
+ m_status_reg |= 0x40;
+ if (!BIT(m_scc_control, 0))
+ set_interrupt(3);
+ }
+ else
+ {
+ m_status_reg &= 0xbf;
+ if (!BIT(m_scc_control, 0))
+ reset_interrupt(3);
+ }
+}
+
+WRITE_LINE_MEMBER(applepic_device::reqa_w)
+{
+}
+
+WRITE_LINE_MEMBER(applepic_device::reqb_w)
+{
+}
+
+u8 applepic_device::timer_r(offs_t offset)
+{
+ u16 reg = BIT(offset, 1) ? m_timer_latch : m_timer_counter;
+ if (BIT(offset, 0))
+ return (reg & 0xff00) >> 8;
+ else
+ {
+ if (offset == 0 && !machine().side_effects_disabled())
+ reset_interrupt(5);
+ return reg & 0x00ff;
+ }
+}
+
+void applepic_device::timer_w(offs_t offset, u8 data)
+{
+ if (BIT(offset, 0))
+ {
+ m_timer_latch = u16(data) << 8 | (m_timer_latch & 0xff00);
+ if (offset == 1)
+ reset_interrupt(5);
+ }
+ else
+ m_timer_latch = (m_timer_latch & 0xff00) | data;
+}
+
+u8 applepic_device::dma_channel_r(offs_t offset)
+{
+ dma_channel &channel = m_dma_channel[BIT(offset, 3)];
+
+ switch (offset & 7)
+ {
+ case 0:
+ return channel.control;
+
+ case 1:
+ return channel.map & 0x00ff;
+
+ case 2:
+ return (channel.map & 0xff00) >> 8;
+
+ case 3:
+ return channel.tc & 0x0ff;
+
+ case 4:
+ return (channel.tc & 0x700) >> 8;
+
+ default:
+ if (!machine().side_effects_disabled())
+ logerror("%s: Read from undefined DMA register $%02X\n", machine().describe_context(), 0x20 + offset);
+ return 0;
+ }
+}
+
+void applepic_device::dma_channel_w(offs_t offset, u8 data)
+{
+ dma_channel &channel = m_dma_channel[BIT(offset, 3)];
+
+ switch (offset & 7)
+ {
+ case 0:
+ channel.control = data;
+ break;
+
+ case 1:
+ channel.map = (channel.map & 0xff00) | data;
+ break;
+
+ case 2:
+ channel.map = u16(data) << 8 | (channel.map & 0x00ff);
+ break;
+
+ case 3:
+ channel.tc = (channel.tc & 0x700) | data;
+ break;
+
+ case 4:
+ channel.tc = (data & 0x07) | (channel.tc & 0x0ff);
+ break;
+
+ default:
+ logerror("%s: Write $%02X to undefined DMA register $%02X\n", machine().describe_context(), data, 0x20 + offset);
+ break;
+ }
+}
+
+u8 applepic_device::scc_control_r()
+{
+ return m_scc_control;
+}
+
+void applepic_device::scc_control_w(u8 data)
+{
+ m_scc_control = data;
+ if (!BIT(data, 0) && BIT(m_status_reg, 6))
+ set_interrupt(3);
+ else
+ reset_interrupt(3);
+ m_gpout_callback[1](BIT(data, 7));
+}
+
+u8 applepic_device::io_control_r()
+{
+ return m_io_control;
+}
+
+void applepic_device::io_control_w(u8 data)
+{
+ m_io_control = data;
+}
+
+u8 applepic_device::timer_dpll_control_r()
+{
+ return m_timer_dpll_control;
+}
+
+void applepic_device::timer_dpll_control_w(u8 data)
+{
+ m_timer_dpll_control = data;
+}
+
+u8 applepic_device::int_mask_r()
+{
+ return m_int_mask;
+}
+
+void applepic_device::int_mask_w(u8 data)
+{
+ for (int which = 1; which <= 5; which++)
+ if (BIT(m_int_mask, which) != BIT(data, which))
+ logerror("%s: %sabling %s interrupt\n", machine().describe_context(), BIT(data, which) ? "En" : "Dis", s_interrupt_names[which]);
+
+ m_int_mask = data & 0x3e;
+ m_iopcpu->set_input_line(r65c02_device::IRQ_LINE, (m_int_mask & m_int_reg) != 0 ? ASSERT_LINE : CLEAR_LINE);
+}
+
+u8 applepic_device::int_reg_r()
+{
+ return m_int_reg;
+}
+
+void applepic_device::int_reg_w(u8 data)
+{
+ if ((m_int_reg & data) != 0)
+ {
+ m_int_reg &= ~data;
+ if ((m_int_mask & m_int_reg) == 0)
+ {
+ logerror("%s: 6502 interrupts acknowledged\n", machine().describe_context());
+ m_iopcpu->set_input_line(r65c02_device::IRQ_LINE, CLEAR_LINE);
+ }
+ }
+}
+
+void applepic_device::set_interrupt(int which)
+{
+ if (!BIT(m_int_reg, which))
+ {
+ logerror("%s: Setting %s interrupt\n", machine().describe_context(), s_interrupt_names[which]);
+ m_int_reg |= (1 << which);
+ if ((m_int_reg & m_int_mask) == (1 << which))
+ m_iopcpu->set_input_line(r65c02_device::IRQ_LINE, ASSERT_LINE);
+ }
+}
+
+void applepic_device::reset_interrupt(int which)
+{
+ if (BIT(m_int_reg, which))
+ {
+ logerror("%s: Resetting %s interrupt\n", machine().describe_context(), s_interrupt_names[which]);
+ if ((m_int_reg & m_int_mask) == (1 << which))
+ m_iopcpu->set_input_line(r65c02_device::IRQ_LINE, CLEAR_LINE);
+ m_int_reg &= ~(1 << which);
+ }
+}
+
+u8 applepic_device::host_reg_r()
+{
+ return (m_status_reg & 0x30) >> 2;
+}
+
+void applepic_device::host_reg_w(u8 data)
+{
+ logerror("%s: INTHST0 %srequested, INTHST1 %srequested\n", machine().describe_context(), BIT(data, 2) ? "" : "not ", BIT(data, 3) ? "" : "not ");
+ m_status_reg |= (data & 0x0c) << 2;
+ if ((data & 0x0c) != 0)
+ m_hint_callback(ASSERT_LINE);
+}
+
+u8 applepic_device::device_reg_r(offs_t offset)
+{
+ if (BIT(m_scc_control, 0))
+ {
+ if (!machine().side_effects_disabled())
+ logerror("%s: Read from device register $%X in bypass mode\n", machine().describe_context(), offset & 0x0f);
+ return 0;
+ }
+ else
+ return m_prd_callback(offset & 0x0f);
+}
+
+void applepic_device::device_reg_w(offs_t offset, u8 data)
+{
+ if (BIT(m_scc_control, 0))
+ logerror("%s: Read from device register $%X in bypass mode\n", machine().describe_context(), offset & 0x0f);
+ else
+ m_pwr_callback(offset & 0x0f, data);
+}