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Diffstat (limited to 'src/devices/bus/bbc/rom/rom.cpp')
-rw-r--r--src/devices/bus/bbc/rom/rom.cpp50
1 files changed, 50 insertions, 0 deletions
diff --git a/src/devices/bus/bbc/rom/rom.cpp b/src/devices/bus/bbc/rom/rom.cpp
new file mode 100644
index 00000000000..f798de11c6a
--- /dev/null
+++ b/src/devices/bus/bbc/rom/rom.cpp
@@ -0,0 +1,50 @@
+// license:BSD-3-Clause
+// copyright-holders:Nigel Barnes
+/***************************************************************************
+
+ BBC Micro Sideways ROM emulation
+
+***************************************************************************/
+
+#include "emu.h"
+#include "rom.h"
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(BBC_ROM, bbc_rom_device, "bbc_rom", "BBC Micro Sideways ROM")
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// bbc_rom_device - constructor
+//-------------------------------------------------
+
+bbc_rom_device::bbc_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+ : device_t(mconfig, BBC_ROM, tag, owner, clock)
+ , device_bbc_rom_interface(mconfig, *this)
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void bbc_rom_device::device_start()
+{
+}
+
+//-------------------------------------------------
+// read
+//-------------------------------------------------
+
+uint8_t bbc_rom_device::read(offs_t offset)
+{
+ uint32_t size = std::min((int32_t)get_rom_size(), 0x4000);
+
+ return get_rom_base()[offset & (size - 1)];
+}