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-rw-r--r--src/mame/machine/prof80mmu.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/src/mame/machine/prof80mmu.c b/src/mame/machine/prof80mmu.c
new file mode 100644
index 00000000000..ebdccf33004
--- /dev/null
+++ b/src/mame/machine/prof80mmu.c
@@ -0,0 +1,127 @@
+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+ Conitec PROF-80 Memory Management Unit emulation
+
+**********************************************************************/
+
+#include "prof80mmu.h"
+
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type PROF80_MMU = &device_creator<prof80_mmu_device>;
+
+
+DEVICE_ADDRESS_MAP_START( z80_program_map, 8, prof80_mmu_device )
+ AM_RANGE(0x0000, 0xffff) AM_READWRITE(program_r, program_w)
+ADDRESS_MAP_END
+
+static ADDRESS_MAP_START( program_map, AS_PROGRAM, 8, prof80_mmu_device )
+ADDRESS_MAP_END
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// prof80_mmu_device - constructor
+//-------------------------------------------------
+
+prof80_mmu_device::prof80_mmu_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, PROF80_MMU, "PROF80_MMU", tag, owner, clock, "prof80_mmu", __FILE__),
+ device_memory_interface(mconfig, *this),
+ m_program_space_config("program", ENDIANNESS_LITTLE, 8, 20, 0, *ADDRESS_MAP_NAME(program_map))
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void prof80_mmu_device::device_start()
+{
+ // state saving
+ save_item(NAME(m_blk));
+ save_item(NAME(m_enabled));
+}
+
+
+//-------------------------------------------------
+// memory_space_config - return a description of
+// any address spaces owned by this device
+//-------------------------------------------------
+
+const address_space_config *prof80_mmu_device::memory_space_config(address_spacenum spacenum) const
+{
+ return (spacenum == AS_PROGRAM) ? &m_program_space_config : NULL;
+}
+
+
+//-------------------------------------------------
+// par_w -
+//-------------------------------------------------
+
+WRITE8_MEMBER( prof80_mmu_device::par_w )
+{
+ int bank = offset >> 12;
+
+ m_blk[bank] = (data & 0x0f) ^ 0x0f;
+}
+
+
+//-------------------------------------------------
+// mme_w -
+//-------------------------------------------------
+
+WRITE_LINE_MEMBER( prof80_mmu_device::mme_w )
+{
+ m_enabled = (state == 1);
+}
+
+
+//-------------------------------------------------
+// program_r - program space read
+//-------------------------------------------------
+
+READ8_MEMBER( prof80_mmu_device::program_r )
+{
+ if (m_enabled)
+ {
+ int bank = offset >> 12;
+ offset |= m_blk[bank] << 16;
+ }
+ else
+ {
+ offset |= 0xf0000;
+ }
+
+ return this->space(AS_PROGRAM).read_byte(offset);
+}
+
+
+//-------------------------------------------------
+// program_w - program space write
+//-------------------------------------------------
+
+WRITE8_MEMBER( prof80_mmu_device::program_w )
+{
+ if (m_enabled)
+ {
+ int bank = offset >> 12;
+ offset |= m_blk[bank] << 16;
+ }
+ else
+ {
+ offset |= 0xf0000;
+ }
+
+ this->space(AS_PROGRAM).write_byte(offset, data);
+}