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-rw-r--r--src/devices/bus/aquarius/supercart.cpp101
1 files changed, 101 insertions, 0 deletions
diff --git a/src/devices/bus/aquarius/supercart.cpp b/src/devices/bus/aquarius/supercart.cpp
new file mode 100644
index 00000000000..2bc2ad82fd8
--- /dev/null
+++ b/src/devices/bus/aquarius/supercart.cpp
@@ -0,0 +1,101 @@
+// license:BSD-3-Clause
+// copyright-holders:Nigel Barnes
+/***************************************************************************
+
+ Aquarius SuperCart Cartridge
+
+***************************************************************************/
+
+#include "emu.h"
+#include "supercart.h"
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(AQUARIUS_SC1, aquarius_sc1_device, "aquarius_sc1", "Aquarius SuperCart I Cartridge")
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// aquarius_sc1_device - constructor
+//-------------------------------------------------
+
+aquarius_sc1_device::aquarius_sc1_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+ : device_t(mconfig, AQUARIUS_SC1, tag, owner, clock)
+ , device_aquarius_cartridge_interface(mconfig, *this)
+ , m_bank(0)
+ , m_mode(0)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void aquarius_sc1_device::device_start()
+{
+ save_item(NAME(m_bank));
+ save_item(NAME(m_mode));
+}
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void aquarius_sc1_device::device_reset()
+{
+ static const unsigned char SC08_HEADER[16] = { 0x53, 0x43, 0x30, 0x38, 0x4b, 0x9c, 0xb5, 0xb0, 0xa8, 0x6c, 0xac, 0x64, 0xcc, 0xa8, 0x06, 0x70 };
+ static const unsigned char SC16_HEADER[16] = { 0x53, 0x43, 0x31, 0x36, 0x4b, 0x9c, 0xb5, 0xb0, 0xa8, 0x6c, 0xac, 0x64, 0xcc, 0xa8, 0x08, 0x70 };
+
+ uint8_t* header = get_rom_base() + get_rom_size() - 0x2000;
+
+ // select bank switching mode
+ if (!memcmp(header, SC08_HEADER, 16))
+ m_mode = 0;
+ else if (!memcmp(header, SC16_HEADER, 16))
+ m_mode = 1;
+ else
+ fatalerror("Invalid SuperCart mode header\n");
+}
+
+
+//**************************************************************************
+// IMPLEMENTATION
+//**************************************************************************
+
+uint8_t aquarius_sc1_device::mreq_ce_r(offs_t offset)
+{
+ switch (m_mode)
+ {
+ case 0: // 8K Mode
+ if (offset & 0x2000)
+ {
+ offset |= get_rom_size() - 0x2000;
+ }
+ else
+ {
+ offset |= m_bank << 13;
+ }
+ break;
+
+ case 1: // 16K Mode
+ offset |= (m_bank & 0x7e) << 13;
+ break;
+ }
+
+ return get_rom_base()[offset & (get_rom_size() - 1)];
+}
+
+void aquarius_sc1_device::mreq_ce_w(offs_t offset, uint8_t data)
+{
+ if (offset & 0x2000)
+ {
+ m_bank = data & 0x7f;
+ }
+}