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-rw-r--r--src/devices/bus/c64/cpm.cpp230
1 files changed, 230 insertions, 0 deletions
diff --git a/src/devices/bus/c64/cpm.cpp b/src/devices/bus/c64/cpm.cpp
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index 00000000000..1533ab9f93b
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+++ b/src/devices/bus/c64/cpm.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+ Commodore 64 CP/M cartridge emulation
+
+ http://www.baltissen.org/newhtm/c64_cpm.htm
+
+**********************************************************************/
+
+/*
+
+ TODO:
+
+ - Z80 clock speed
+
+*/
+
+#include "cpm.h"
+
+
+
+//**************************************************************************
+// MACROS/CONSTANTS
+//**************************************************************************
+
+#define Z80_TAG "z80"
+
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type C64_CPM = &device_creator<c64_cpm_cartridge_device>;
+
+
+//-------------------------------------------------
+// ADDRESS_MAP( z80_mem )
+//-------------------------------------------------
+
+static ADDRESS_MAP_START( z80_mem, AS_PROGRAM, 8, c64_cpm_cartridge_device )
+ AM_RANGE(0x0000, 0xffff) AM_READWRITE(dma_r, dma_w)
+ADDRESS_MAP_END
+
+
+//-------------------------------------------------
+// ADDRESS_MAP( z80_io )
+//-------------------------------------------------
+
+static ADDRESS_MAP_START( z80_io, AS_IO, 8, c64_cpm_cartridge_device )
+ AM_RANGE(0x0000, 0xffff) AM_READWRITE(dma_r, dma_w)
+ADDRESS_MAP_END
+
+
+//-------------------------------------------------
+// MACHINE_CONFIG_FRAGMENT( c64_cpm )
+//-------------------------------------------------
+
+static MACHINE_CONFIG_FRAGMENT( c64_cpm )
+ MCFG_CPU_ADD(Z80_TAG, Z80, 3000000)
+ MCFG_CPU_PROGRAM_MAP(z80_mem)
+ MCFG_CPU_IO_MAP(z80_io)
+MACHINE_CONFIG_END
+
+
+//-------------------------------------------------
+// machine_config_additions - device-specific
+// machine configurations
+//-------------------------------------------------
+
+machine_config_constructor c64_cpm_cartridge_device::device_mconfig_additions() const
+{
+ return MACHINE_CONFIG_NAME( c64_cpm );
+}
+
+
+
+//**************************************************************************
+// INLINE HELPERS
+//**************************************************************************
+
+//-------------------------------------------------
+// update_signals -
+//-------------------------------------------------
+
+inline void c64_cpm_cartridge_device::update_signals()
+{
+ if (m_enabled)
+ {
+ m_maincpu->set_input_line(INPUT_LINE_HALT, CLEAR_LINE);
+ m_slot->dma_w(ASSERT_LINE);
+
+ if (m_reset)
+ {
+ m_maincpu->reset();
+ m_maincpu->set_state_int(Z80_PC, 0);
+ m_reset = 0;
+ }
+ }
+ else
+ {
+ m_maincpu->set_input_line(INPUT_LINE_HALT, ASSERT_LINE);
+ m_slot->dma_w(CLEAR_LINE);
+ }
+
+/*
+ // NOTE: the following is how it actually works once the Z80 core has been rewritten
+
+ // C64 DMA
+ m_slot->dma_w(m_enabled ? ASSERT_LINE : CLEAR_LINE);
+
+ // Z80 BUSRQ
+ int busrq = !(m_enabled & !m_ba) ? CLEAR_LINE : ASSERT_LINE;
+ m_maincpu->set_input_line(Z80_INPUT_LINE_BUSRQ, busrq);
+
+ // Z80 WAIT
+ m_maincpu->set_input_line(Z80_INPUT_LINE_WAIT, m_enabled ? CLEAR_LINE : ASSERT_LINE);
+*/
+}
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// c64_cpm_cartridge_device - constructor
+//-------------------------------------------------
+
+c64_cpm_cartridge_device::c64_cpm_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+ device_t(mconfig, C64_CPM, "C64 CP/M cartridge", tag, owner, clock, "c64_cpm", __FILE__),
+ device_c64_expansion_card_interface(mconfig, *this),
+ m_maincpu(*this, Z80_TAG),
+ m_enabled(0),
+ m_ba(1)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void c64_cpm_cartridge_device::device_start()
+{
+ // state saving
+ save_item(NAME(m_enabled));
+ save_item(NAME(m_ba));
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void c64_cpm_cartridge_device::device_reset()
+{
+ m_enabled = 0;
+ m_reset = 1;
+
+ update_signals();
+}
+
+
+//-------------------------------------------------
+// c64_cd_w - cartridge data write
+//-------------------------------------------------
+
+void c64_cpm_cartridge_device::c64_cd_w(address_space &space, offs_t offset, UINT8 data, int sphi2, int ba, int roml, int romh, int io1, int io2)
+{
+ if (!io1)
+ {
+ m_enabled = !BIT(data, 0);
+
+ update_signals();
+ }
+}
+
+
+//-------------------------------------------------
+// c64_game_r - GAME read
+//-------------------------------------------------
+
+int c64_cpm_cartridge_device::c64_game_r(offs_t offset, int sphi2, int ba, int rw)
+{
+ if (m_ba != ba)
+ {
+ m_ba = ba;
+
+ update_signals();
+ }
+
+ return 1;
+}
+
+
+//-------------------------------------------------
+// dma_r -
+//-------------------------------------------------
+
+READ8_MEMBER( c64_cpm_cartridge_device::dma_r )
+{
+ UINT8 data = 0xff;
+
+ if (m_enabled)
+ {
+ offs_t addr = (offset + 0x1000) & 0xffff;
+
+ data = m_slot->dma_cd_r(space, addr);
+ }
+
+ return data;
+}
+
+
+//-------------------------------------------------
+// dma_w -
+//-------------------------------------------------
+
+WRITE8_MEMBER( c64_cpm_cartridge_device::dma_w )
+{
+ if (m_enabled)
+ {
+ offs_t addr = (offset + 0x1000) & 0xffff;
+
+ m_slot->dma_cd_w(space, addr, data);
+ }
+}