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Diffstat (limited to 'src/devices/bus/cbm2/24k.c')
-rw-r--r--src/devices/bus/cbm2/24k.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/src/devices/bus/cbm2/24k.c b/src/devices/bus/cbm2/24k.c
new file mode 100644
index 00000000000..a31c58a7aaf
--- /dev/null
+++ b/src/devices/bus/cbm2/24k.c
@@ -0,0 +1,88 @@
+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+ GLA 24K RAM cartridge emulation
+
+**********************************************************************/
+
+#include "24k.h"
+
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type CBM2_24K = &device_creator<cbm2_24k_cartridge_device>;
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// cbm2_24k_cartridge_device - constructor
+//-------------------------------------------------
+
+cbm2_24k_cartridge_device::cbm2_24k_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+ device_t(mconfig, CBM2_24K, "24K RAM/ROM cartridge", tag, owner, clock, "cbm2_24k", __FILE__),
+ device_cbm2_expansion_card_interface(mconfig, *this),
+ m_ram(*this, "ram")
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void cbm2_24k_cartridge_device::device_start()
+{
+ m_ram.allocate(0x6000);
+}
+
+
+//-------------------------------------------------
+// cbm2_bd_r - cartridge data read
+//-------------------------------------------------
+
+UINT8 cbm2_24k_cartridge_device::cbm2_bd_r(address_space &space, offs_t offset, UINT8 data, int csbank1, int csbank2, int csbank3)
+{
+ if (!csbank1)
+ {
+ data = m_ram[offset];
+ }
+ else if (!csbank2)
+ {
+ data = m_ram[0x2000 | offset];
+ }
+ else if (!csbank3)
+ {
+ data = m_ram[0x4000 | offset];
+ }
+
+ return data;
+}
+
+
+//-------------------------------------------------
+// cbm2_bd_w - cartridge data write
+//-------------------------------------------------
+
+void cbm2_24k_cartridge_device::cbm2_bd_w(address_space &space, offs_t offset, UINT8 data, int csbank1, int csbank2, int csbank3)
+{
+ if (!csbank1)
+ {
+ m_ram[offset] = data;
+ }
+ else if (!csbank2)
+ {
+ m_ram[0x2000 | offset] = data;
+ }
+ else if (!csbank3)
+ {
+ m_ram[0x4000 | offset] = data;
+ }
+}