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-rw-r--r--src/devices/bus/c64/silverrock.cpp132
1 files changed, 132 insertions, 0 deletions
diff --git a/src/devices/bus/c64/silverrock.cpp b/src/devices/bus/c64/silverrock.cpp
new file mode 100644
index 00000000000..9e9ce421a6c
--- /dev/null
+++ b/src/devices/bus/c64/silverrock.cpp
@@ -0,0 +1,132 @@
+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+ SilverRock Productions cartridge emulation
+
+**********************************************************************/
+
+/*
+
+ PCB Layout
+ ----------
+
+ e9048
+ |=============|
+ |=| LS00 |
+ |=| LS273|
+ |=| |
+ |=| |
+ |=| ROM |
+ |=| |
+ |=| |
+ |=| |
+ |=============|
+
+ ROM - Atmel AT27C010-25PC 128Kx8 OTP EPROM "HUGO 2012"
+
+*/
+
+#include "silverrock.h"
+
+
+
+//**************************************************************************
+// MACROS/CONSTANTS
+//**************************************************************************
+
+#define UNSCRAMBLE_ADDRESS(_offset) \
+ BITSWAP16(_offset,15,14,13,12,1,0,2,3,11,10,9,8,7,6,5,4)
+
+#define UNSCRAMBLE_DATA(_data) \
+ BITSWAP8(_data,7,6,5,4,0,1,2,3)
+
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type C64_SILVERROCK = &device_creator<c64_silverrock_cartridge_device>;
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// c64_silverrock_cartridge_device - constructor
+//-------------------------------------------------
+
+c64_silverrock_cartridge_device::c64_silverrock_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+ device_t(mconfig, C64_SILVERROCK, "C64 SilverRock cartridge", tag, owner, clock, "c64_silverrock", __FILE__),
+ device_c64_expansion_card_interface(mconfig, *this)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void c64_silverrock_cartridge_device::device_start()
+{
+ // state saving
+ save_item(NAME(m_bank));
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void c64_silverrock_cartridge_device::device_reset()
+{
+ m_bank = 0;
+}
+
+
+//-------------------------------------------------
+// c64_cd_r - cartridge data read
+//-------------------------------------------------
+
+UINT8 c64_silverrock_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);
+ addr = (addr & 0x10000) | UNSCRAMBLE_ADDRESS(addr);
+ data = UNSCRAMBLE_DATA(m_roml[addr]);
+ }
+
+ return data;
+}
+
+
+//-------------------------------------------------
+// c64_cd_w - cartridge data write
+//-------------------------------------------------
+
+void c64_silverrock_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)
+ {
+ /*
+
+ bit description
+
+ 0
+ 1
+ 2
+ 3
+ 4 A14
+ 5 A15
+ 6 A16
+ 7 A13
+
+ */
+
+ m_bank = ((data >> 3) & 0x0e) | BIT(data, 7);
+ }
+}