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-rw-r--r--src/mess/video/iq151_video32.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/src/mess/video/iq151_video32.c b/src/mess/video/iq151_video32.c
new file mode 100644
index 00000000000..14ca59b746e
--- /dev/null
+++ b/src/mess/video/iq151_video32.c
@@ -0,0 +1,148 @@
+/***************************************************************************
+
+ IQ151 video32 cartridge emulation
+
+***************************************************************************/
+
+#include "emu.h"
+#include "iq151_video32.h"
+
+
+/***************************************************************************
+ IMPLEMENTATION
+***************************************************************************/
+
+ROM_START( iq151_video32 )
+ ROM_REGION(0x0400, "chargen", ROMREGION_INVERT)
+ ROM_LOAD( "iq151_video32font.rom", 0x0000, 0x0400, CRC(395567a7) SHA1(18800543daf4daed3f048193c6ae923b4b0e87db))
+
+ ROM_REGION(0x0400, "videoram", ROMREGION_ERASE)
+ROM_END
+
+
+/* F4 Character Displayer */
+static const gfx_layout iq151_video32_charlayout =
+{
+ 8, 8, /* 8 x 8 characters */
+ 128, /* 128 characters */
+ 1, /* 1 bits per pixel */
+ { 0 }, /* no bitplanes */
+ /* x offsets */
+ { 0, 1, 2, 3, 4, 5, 6, 7 },
+ /* y offsets */
+ { 0*8, 1*8, 2*8, 3*8, 4*8, 5*8, 6*8, 7*8 },
+ 8*8 /* every char takes 8 bytes */
+};
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+const device_type IQ151_VIDEO32 = &device_creator<iq151_video32_device>;
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// iq151_video32_device - constructor
+//-------------------------------------------------
+
+iq151_video32_device::iq151_video32_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, IQ151_VIDEO32, "IQ151 video32", tag, owner, clock),
+ device_iq151cart_interface( mconfig, *this )
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void iq151_video32_device::device_start()
+{
+ m_videoram = (UINT8*)memregion("videoram")->base();
+ m_chargen = (UINT8*)memregion("chargen")->base();
+
+ machine().gfx[0] = gfx_element_alloc(machine(), &iq151_video32_charlayout, m_chargen, 1, 0);
+}
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void iq151_video32_device::device_reset()
+{
+ screen_device *screen = machine().primary_screen;
+
+ // if required adjust screen size
+ if (screen->visible_area().max_x < 32*8 - 1)
+ screen->set_visible_area(0, 32*8-1, 0, 32*8-1);
+}
+
+//-------------------------------------------------
+// device_rom_region
+//-------------------------------------------------
+
+const rom_entry *iq151_video32_device::device_rom_region() const
+{
+ return ROM_NAME( iq151_video32 );
+}
+
+//-------------------------------------------------
+// read
+//-------------------------------------------------
+
+void iq151_video32_device::read(offs_t offset, UINT8 &data)
+{
+ // videoram is mapped at 0xec00-0xefff
+ if (offset >= 0xec00 && offset < 0xf000)
+ data = m_videoram[offset & 0x3ff];
+}
+
+//-------------------------------------------------
+// write
+//-------------------------------------------------
+
+void iq151_video32_device::write(offs_t offset, UINT8 data)
+{
+ if (offset >= 0xec00 && offset < 0xf000)
+ m_videoram[offset & 0x3ff] = data;
+}
+
+//-------------------------------------------------
+// video update
+//-------------------------------------------------
+
+void iq151_video32_device::video_update(bitmap_ind16 &bitmap, const rectangle &cliprect)
+{
+ UINT16 ma = 0, sy = 0;
+
+ for (int y = 0; y < 32; y++)
+ {
+ for (int ra = 0; ra < 8; ra++)
+ {
+ UINT16 *p = &bitmap.pix16(sy++);
+
+ for (int x = ma; x < ma + 32; x++)
+ {
+ UINT8 chr = m_videoram[x] & 0x7f; // rom only has 128 characters
+ UINT8 gfx = m_chargen[(chr<<3) | ra ];
+
+ // chars above 0x7f have colors inverted
+ if (m_videoram[x] > 0x7f)
+ gfx = ~gfx;
+
+ /* Display a scanline of a character */
+ *p++ |= BIT(gfx, 7);
+ *p++ |= BIT(gfx, 6);
+ *p++ |= BIT(gfx, 5);
+ *p++ |= BIT(gfx, 4);
+ *p++ |= BIT(gfx, 3);
+ *p++ |= BIT(gfx, 2);
+ *p++ |= BIT(gfx, 1);
+ *p++ |= BIT(gfx, 0);
+ }
+ }
+ ma += 32;
+ }
+}