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-rw-r--r--src/devices/bus/spc1000/vdp.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/src/devices/bus/spc1000/vdp.c b/src/devices/bus/spc1000/vdp.c
new file mode 100644
index 00000000000..7824e9fccb4
--- /dev/null
+++ b/src/devices/bus/spc1000/vdp.c
@@ -0,0 +1,106 @@
+// license:BSD-3-Clause
+// copyright-holders:Fabio Priuli
+/***************************************************************************
+
+ SPC-1000 VDP expansion unit
+
+***************************************************************************/
+
+#include "emu.h"
+#include "vdp.h"
+
+
+/***************************************************************************
+ IMPLEMENTATION
+***************************************************************************/
+
+WRITE_LINE_MEMBER(spc1000_vdp_exp_device::vdp_interrupt)
+{
+ // nothing here?
+}
+
+static MACHINE_CONFIG_FRAGMENT(scp1000_vdp)
+
+ MCFG_DEVICE_ADD("tms", TMS9928A, XTAL_10_738635MHz / 2) // TODO: which clock?
+ MCFG_TMS9928A_VRAM_SIZE(0x4000)
+ MCFG_TMS9928A_OUT_INT_LINE_CB(WRITELINE(spc1000_vdp_exp_device, vdp_interrupt))
+ MCFG_TMS9928A_SCREEN_ADD_NTSC("tms_screen")
+ MCFG_SCREEN_UPDATE_DEVICE("tms", tms9928a_device, screen_update)
+MACHINE_CONFIG_END
+
+//-------------------------------------------------
+// device_mconfig_additions
+//-------------------------------------------------
+
+machine_config_constructor spc1000_vdp_exp_device::device_mconfig_additions() const
+{
+ return MACHINE_CONFIG_NAME( scp1000_vdp );
+}
+
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+const device_type SPC1000_VDP_EXP = &device_creator<spc1000_vdp_exp_device>;
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// spc1000_vdp_exp_device - constructor
+//-------------------------------------------------
+
+spc1000_vdp_exp_device::spc1000_vdp_exp_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, SPC1000_VDP_EXP, "SPC1000 VDP expansion", tag, owner, clock, "spc1000_vdp_exp", __FILE__),
+ device_spc1000_card_interface(mconfig, *this),
+ m_vdp(*this, "tms")
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void spc1000_vdp_exp_device::device_start()
+{
+}
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void spc1000_vdp_exp_device::device_reset()
+{
+}
+
+/*-------------------------------------------------
+ read
+-------------------------------------------------*/
+READ8_MEMBER(spc1000_vdp_exp_device::read)
+{
+ if (!(offset & 0x800))
+ return 0xff;
+
+ if (offset & 1)
+ return m_vdp->register_read(space, offset);
+ else
+ return m_vdp->vram_read(space, offset);
+}
+
+//-------------------------------------------------
+// write
+//-------------------------------------------------
+
+WRITE8_MEMBER(spc1000_vdp_exp_device::write)
+{
+ if (offset & 0x800)
+ {
+ if (offset & 1)
+ m_vdp->register_write(space, offset, data);
+ else
+ m_vdp->vram_write(space, offset, data);
+ }
+}