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-rw-r--r--src/devices/bus/c64/structured_basic.cpp103
1 files changed, 103 insertions, 0 deletions
diff --git a/src/devices/bus/c64/structured_basic.cpp b/src/devices/bus/c64/structured_basic.cpp
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index 00000000000..404d1b9d753
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+++ b/src/devices/bus/c64/structured_basic.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+ Structured Basic cartridge emulation
+
+**********************************************************************/
+
+#include "structured_basic.h"
+
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type C64_STRUCTURED_BASIC = &device_creator<c64_structured_basic_cartridge_device>;
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// c64_structured_basic_cartridge_device - constructor
+//-------------------------------------------------
+
+c64_structured_basic_cartridge_device::c64_structured_basic_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+ device_t(mconfig, C64_STRUCTURED_BASIC, "C64 Structured Basic cartridge", tag, owner, clock, "c64_structured_basic", __FILE__),
+ device_c64_expansion_card_interface(mconfig, *this)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void c64_structured_basic_cartridge_device::device_start()
+{
+ // state saving
+ save_item(NAME(m_bank));
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void c64_structured_basic_cartridge_device::device_reset()
+{
+ m_exrom = 0;
+
+ m_bank = 0;
+}
+
+
+//-------------------------------------------------
+// c64_cd_r - cartridge data read
+//-------------------------------------------------
+
+UINT8 c64_structured_basic_cartridge_device::c64_cd_r(address_space &space, offs_t offset, UINT8 data, int sphi2, int ba, int roml, int romh, int io1, int io2)
+{
+ if (!roml)
+ {
+ offs_t addr = (m_bank << 13) | (offset & 0x1fff);
+
+ data = m_roml[addr];
+ }
+
+ return data;
+}
+
+
+//-------------------------------------------------
+// c64_cd_w - cartridge data write
+//-------------------------------------------------
+
+void c64_structured_basic_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)
+ {
+ switch (data & 0x03)
+ {
+ case 0:
+ case 1:
+ m_exrom = 0;
+ m_bank = 0;
+ break;
+
+ case 2:
+ m_exrom = 0;
+ m_bank = 1;
+ break;
+
+ case 3:
+ m_exrom = 1;
+ m_bank = 0;
+ break;
+ }
+ }
+}