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Diffstat (limited to 'src/mame/video/v1050.c')
-rw-r--r--src/mame/video/v1050.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/src/mame/video/v1050.c b/src/mame/video/v1050.c
new file mode 100644
index 00000000000..2154b01fb42
--- /dev/null
+++ b/src/mame/video/v1050.c
@@ -0,0 +1,124 @@
+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+#include "includes/v1050.h"
+
+/*
+
+ TODO:
+
+ - bright in reverse video
+
+*/
+
+#define V1050_ATTR_BRIGHT 0x01
+#define V1050_ATTR_BLINKING 0x02
+#define V1050_ATTR_ATTEN 0x04
+#define V1050_ATTR_REVERSE 0x10
+#define V1050_ATTR_BLANK 0x20
+#define V1050_ATTR_BOLD 0x40
+#define V1050_ATTR_BLINK 0x80
+
+/* Video RAM Access */
+
+READ8_MEMBER( v1050_state::attr_r )
+{
+ return m_attr;
+}
+
+WRITE8_MEMBER( v1050_state::attr_w )
+{
+ m_attr = data;
+}
+
+READ8_MEMBER( v1050_state::videoram_r )
+{
+ if (offset >= 0x2000)
+ {
+ m_attr = (m_attr & 0xfc) | (m_attr_ram[offset] & 0x03);
+ }
+
+ return m_video_ram[offset];
+}
+
+WRITE8_MEMBER( v1050_state::videoram_w )
+{
+ m_video_ram[offset] = data;
+
+ if (offset >= 0x2000 && BIT(m_attr, 2))
+ {
+ m_attr_ram[offset] = m_attr & 0x03;
+ }
+}
+
+/* MC6845 Interface */
+
+MC6845_UPDATE_ROW( v1050_state::crtc_update_row )
+{
+ int column, bit;
+
+ for (column = 0; column < x_count; column++)
+ {
+ UINT16 address = (((ra & 0x03) + 1) << 13) | ((ma & 0x1fff) + column);
+ UINT8 data = m_video_ram[address & V1050_VIDEORAM_MASK];
+ UINT8 attr = (m_attr & 0xfc) | (m_attr_ram[address] & 0x03);
+
+ for (bit = 0; bit < 8; bit++)
+ {
+ int x = (column * 8) + bit;
+ int color = BIT(data, 7);
+
+ /* blinking */
+ if ((attr & V1050_ATTR_BLINKING) && !(attr & V1050_ATTR_BLINK)) color = 0;
+
+ /* reverse video */
+ color ^= BIT(attr, 4);
+
+ /* bright */
+ if (color && (!(attr & V1050_ATTR_BOLD) ^ (attr & V1050_ATTR_BRIGHT))) color = 2;
+
+ /* display blank */
+ if (attr & V1050_ATTR_BLANK) color = 0;
+
+ bitmap.pix32(vbp + y, hbp + x) = m_palette->pen(de ? color : 0);
+
+ data <<= 1;
+ }
+ }
+}
+
+WRITE_LINE_MEMBER( v1050_state::crtc_vs_w )
+{
+ m_subcpu->set_input_line(INPUT_LINE_IRQ0, state ? ASSERT_LINE : CLEAR_LINE);
+
+ set_interrupt(INT_VSYNC, state);
+}
+
+/* Video Start */
+
+void v1050_state::video_start()
+{
+ /* allocate memory */
+ m_attr_ram.allocate(V1050_VIDEORAM_SIZE);
+
+ /* register for state saving */
+ save_item(NAME(m_attr));
+}
+
+/* Machine Drivers */
+
+MACHINE_CONFIG_FRAGMENT( v1050_video )
+ MCFG_MC6845_ADD(H46505_TAG, H46505, SCREEN_TAG, XTAL_15_36MHz/8)
+ MCFG_MC6845_SHOW_BORDER_AREA(true)
+ MCFG_MC6845_CHAR_WIDTH(8)
+ MCFG_MC6845_UPDATE_ROW_CB(v1050_state, crtc_update_row)
+ MCFG_MC6845_OUT_VSYNC_CB(WRITELINE(v1050_state, crtc_vs_w))
+
+ MCFG_SCREEN_ADD(SCREEN_TAG, RASTER)
+ MCFG_SCREEN_UPDATE_DEVICE(H46505_TAG, h46505_device, screen_update)
+ MCFG_SCREEN_REFRESH_RATE(60)
+ MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500))
+ MCFG_SCREEN_SIZE(640, 400)
+ MCFG_SCREEN_VISIBLE_AREA(0,640-1, 0, 400-1)
+
+ MCFG_PALETTE_ADD_MONOCHROME_GREEN_HIGHLIGHT("palette")
+MACHINE_CONFIG_END