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-rw-r--r--src/devices/video/m50458.cpp449
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diff --git a/src/devices/video/m50458.cpp b/src/devices/video/m50458.cpp
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+// license:LGPL-2.1+
+// copyright-holders:Angelo Salese
+/***************************************************************************
+
+ Mitsubishi M50458 OSD chip
+
+ device by Angelo Salese
+
+ TODO:
+ - vertical scrolling needs references (might work differently and/or in
+ "worse" ways, the one currently implemented guesses that the screen is
+ masked at the top and the end when in scrolling mode).
+ - Understand what the "vertical start position" really does (vblank?)
+ - Check if the ROM source is actually 2bpp once that a redump is made
+ (the shadow ROM copy doesn't convince me 100%);
+
+***************************************************************************/
+
+#include "emu.h"
+#include "video/m50458.h"
+
+
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+// device type definition
+const device_type M50458 = &device_creator<m50458_device>;
+
+static ADDRESS_MAP_START( m50458_vram, AS_0, 16, m50458_device )
+ AM_RANGE(0x0000, 0x023f) AM_RAM // vram
+ AM_RANGE(0x0240, 0x0241) AM_WRITE(vreg_120_w)
+ AM_RANGE(0x0242, 0x0243) AM_WRITE(vreg_121_w)
+ AM_RANGE(0x0244, 0x0245) AM_WRITE(vreg_122_w)
+ AM_RANGE(0x0246, 0x0247) AM_WRITE(vreg_123_w)
+ AM_RANGE(0x0248, 0x0249) AM_WRITE(vreg_124_w)
+ AM_RANGE(0x024a, 0x024b) AM_WRITE(vreg_125_w)
+ AM_RANGE(0x024c, 0x024d) AM_WRITE(vreg_126_w)
+ AM_RANGE(0x024e, 0x024f) AM_WRITE(vreg_127_w)
+ADDRESS_MAP_END
+
+// internal GFX ROM (TODO: GFXs in here should be 12x18, not 16x18)
+// (also note: ROM length CAN'T be 0x1200)
+ROM_START( m50458 )
+ ROM_REGION( 0x1200, "m50458", 0 )
+ ROM_LOAD("m50458-001sp", 0x0000, 0x1200, BAD_DUMP CRC(444f597d) SHA1(96beda6aba3d9f7bb781a3cd0352ed6ae45e2ebe) )
+ ROM_LOAD("m50458_char.bin", 0x0000, 0x1200, BAD_DUMP CRC(011cc342) SHA1(d5b9f32d6e251b4b25945267d7c68c099bd83e96) )
+ROM_END
+
+WRITE16_MEMBER( m50458_device::vreg_120_w)
+{
+// printf("%04x\n",data);
+}
+
+WRITE16_MEMBER( m50458_device::vreg_121_w)
+{
+ /* Horizontal char size for line 0 */
+ m_hsz1 = (data & 0xc0) >> 6;
+
+ /* Horizontal char size for line 1 - 10 */
+ m_hsz2 = (data & 0x300) >> 8;
+
+ /* Horizontal char size for line 11 */
+ m_hsz3 = (data & 0xc00) >> 10;
+}
+
+
+WRITE16_MEMBER( m50458_device::vreg_122_w)
+{
+ /* Vertical char size for line 0 */
+ m_vsz1 = (data & 0xc0) >> 6;
+
+ /* Vertical char size for line 1 - 10 */
+ m_vsz2 = (data & 0x300) >> 8;
+
+ /* Vertical char size for line 11 */
+ m_vsz3 = (data & 0xc00) >> 10;
+
+}
+
+WRITE16_MEMBER( m50458_device::vreg_123_w)
+{
+ /* fractional part of vertical scrolling */
+ m_scrf = data & 0x1f;
+
+ m_space = (data & 0x60) >> 5;
+
+ /* char part of vertical scrolling */
+ m_scrr = (data & 0x0f00) >> 8;
+
+// printf("%02x %02x %02x\n",m_scrr,m_scrf,m_space);
+}
+
+WRITE16_MEMBER( m50458_device::vreg_124_w)
+{
+}
+
+WRITE16_MEMBER( m50458_device::vreg_125_w)
+{
+ /* blinking cycle */
+ m_blink = data & 4 ? 0x20 : 0x40;
+}
+
+WRITE16_MEMBER( m50458_device::vreg_126_w)
+{
+ /* Raster Color Setting */
+ m_phase = data & 7;
+
+ //printf("%04x\n",data);
+}
+
+
+WRITE16_MEMBER( m50458_device::vreg_127_w)
+{
+ if(data & 0x20) // RAMERS, display RAM is erased
+ {
+ int i;
+
+ for(i=0;i<0x120;i++)
+ write_word(i,0x007f);
+ }
+}
+
+//-------------------------------------------------
+// rom_region - device-specific ROM region
+//-------------------------------------------------
+
+const rom_entry *m50458_device::device_rom_region() const
+{
+ return ROM_NAME( m50458 );
+}
+
+//-------------------------------------------------
+// memory_space_config - return a description of
+// any address spaces owned by this device
+//-------------------------------------------------
+
+const address_space_config *m50458_device::memory_space_config(address_spacenum spacenum) const
+{
+ return (spacenum == AS_0) ? &m_space_config : NULL;
+}
+
+//**************************************************************************
+// INLINE HELPERS
+//**************************************************************************
+
+//-------------------------------------------------
+// read_word - read a word at the given address
+//-------------------------------------------------
+
+inline UINT16 m50458_device::read_word(offs_t address)
+{
+ return space().read_word(address << 1);
+}
+
+//-------------------------------------------------
+// write_word - write a word at the given address
+//-------------------------------------------------
+
+inline void m50458_device::write_word(offs_t address, UINT16 data)
+{
+ space().write_word(address << 1, data);
+}
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// m50458_device - constructor
+//-------------------------------------------------
+
+m50458_device::m50458_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, M50458, "M50458 OSD", tag, owner, clock, "m50458", __FILE__),
+ device_memory_interface(mconfig, *this),
+ device_video_interface(mconfig, *this),
+ m_space_config("videoram", ENDIANNESS_LITTLE, 16, 16, 0, NULL, *ADDRESS_MAP_NAME(m50458_vram))
+{
+}
+
+
+//-------------------------------------------------
+// device_validity_check - perform validity checks
+// on this device
+//-------------------------------------------------
+
+void m50458_device::device_validity_check(validity_checker &valid) const
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void m50458_device::device_start()
+{
+ UINT16 tmp;
+ UINT8 *pcg = memregion("m50458")->base();
+ int tile;
+ int yi;
+ UINT16 src,dst;
+
+ /* Create an array for shadow gfx */
+ /* this will spread the source ROM into four directions (up-left, up-right, down-left, down-right) thus creating a working shadow copy */
+ m_shadow_gfx = auto_alloc_array_clear(machine(), UINT8, 0x1200);
+
+ for(tile=0;tile<0x80;tile++)
+ {
+ for(yi=1;yi<17;yi++)
+ {
+ src = (tile & 0x7f)*36+yi*2; /* source offset */
+
+ dst = (tile & 0x7f)*36+(yi-1)*2; /* destination offset */
+
+ tmp = (((pcg[src]<<8)|(pcg[src+1]&0xff)) & 0xfffe) >> 1;
+
+ m_shadow_gfx[dst+1] |= tmp & 0xff;
+ m_shadow_gfx[dst] |= (tmp >> 8);
+
+ tmp = (((pcg[src]<<8)|(pcg[src+1]&0xff)) & 0x7fff) << 1;
+
+ m_shadow_gfx[dst+1] |= tmp & 0xff;
+ m_shadow_gfx[dst] |= (tmp >> 8);
+
+ dst = (tile & 0x7f)*36+(yi+1)*2; /* destination offset */
+
+ tmp = (((pcg[src]<<8)|(pcg[src+1]&0xff)) & 0xfffe) >> 1;
+
+ m_shadow_gfx[dst+1] |= tmp & 0xff;
+ m_shadow_gfx[dst] |= (tmp >> 8);
+
+ tmp = (((pcg[src]<<8)|(pcg[src+1]&0xff)) & 0x7fff) << 1;
+
+ m_shadow_gfx[dst+1] |= tmp & 0xff;
+ m_shadow_gfx[dst] |= (tmp >> 8);
+ }
+ }
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void m50458_device::device_reset()
+{
+ int i;
+
+ /* clear VRAM at boot */
+ for(i=0;i<0x120;i++)
+ write_word(i,0x007f);
+
+ m_blink = 0x40;
+}
+
+
+//**************************************************************************
+// READ/WRITE HANDLERS
+//**************************************************************************
+
+WRITE_LINE_MEMBER( m50458_device::write_bit )
+{
+ m_latch = state;
+}
+
+WRITE_LINE_MEMBER( m50458_device::set_cs_line )
+{
+ m_reset_line = state;
+
+ if(m_reset_line != CLEAR_LINE)
+ {
+ //printf("Reset asserted\n");
+ m_cmd_stream_pos = 0;
+ m_current_cmd = 0;
+ m_osd_state = OSD_SET_ADDRESS;
+ }
+}
+
+
+WRITE_LINE_MEMBER( m50458_device::set_clock_line )
+{
+ if (m_reset_line == CLEAR_LINE)
+ {
+ if(state == 1)
+ {
+ //printf("%d\n",m_latch);
+
+ m_current_cmd = (m_current_cmd >> 1) | ((m_latch<<15)&0x8000);
+ m_cmd_stream_pos++;
+
+ if(m_cmd_stream_pos == 16)
+ {
+ switch(m_osd_state)
+ {
+ case OSD_SET_ADDRESS:
+ m_osd_addr = m_current_cmd;
+ m_osd_state = OSD_SET_DATA;
+ break;
+ case OSD_SET_DATA:
+ //if(m_osd_addr >= 0x120)
+ //printf("%04x %04x\n",m_osd_addr,m_current_cmd);
+ write_word(m_osd_addr,m_current_cmd);
+ m_osd_addr++;
+ /* Presumably wraps at 0x127? */
+ if(m_osd_addr > 0x127) { m_osd_addr = 0; }
+ break;
+ }
+
+ m_cmd_stream_pos = 0;
+ m_current_cmd = 0;
+ }
+ }
+ }
+}
+
+//-------------------------------------------------
+// update_screen -
+//-------------------------------------------------
+
+UINT32 m50458_device::screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
+{
+ int x,y;
+ UINT8 *pcg = memregion("m50458")->base();
+ UINT8 bg_r,bg_g,bg_b;
+
+ /* TODO: there's probably a way to control the brightness in this */
+ bg_r = m_phase & 1 ? 0xdf : 0;
+ bg_g = m_phase & 2 ? 0xdf : 0;
+ bg_b = m_phase & 4 ? 0xdf : 0;
+ bitmap.fill(rgb_t(0xff,bg_r,bg_g,bg_b),cliprect);
+
+ for(y=0;y<12;y++)
+ {
+ for(x=0;x<24;x++)
+ {
+ int xi,yi;
+ UINT16 tile;
+ int y_base = y;
+
+ if(y != 0 && m_scrr > 1) { y_base+=(m_scrr - 1); }
+ if(y_base > 11) { y_base -= 11; }
+ if(m_scrr && y == 11) { y_base = 0; } /* Guess: repeat line 0 if scrolling is active */
+
+ tile = read_word(x+y_base*24);
+
+ for(yi=0;yi<18;yi++)
+ {
+ for(xi=4;xi<16;xi++) /* TODO: remove 4 / 16 / -4 offset once that the ROM is fixed */
+ {
+ UINT8 pix;
+ UINT8 color = (tile & 0x700) >> 8;
+ UINT16 offset = ((tile & 0x7f)*36+yi*2);
+ int res_y,res_x;
+ UINT8 xh,yh;
+
+ if(xi>=8)
+ pix = ((pcg[offset+1] >> (7-(xi & 0x7))) & 1) << 1;
+ else
+ pix = ((pcg[offset+0] >> (7-(xi & 0x7))) & 1) << 1;
+
+ if(xi>=8)
+ pix |= ((m_shadow_gfx[offset+1] >> (7-(xi & 0x7))) & 1);
+ else
+ pix |= ((m_shadow_gfx[offset+0] >> (7-(xi & 0x7))) & 1);
+
+ /* blinking, VERY preliminary */
+ if(tile & 0x800 && m_screen->frame_number() & m_blink)
+ pix = 0;
+
+ if(yi == 17 && tile & 0x1000) /* underline? */
+ pix |= 1;
+
+ res_y = y*18+yi;
+ res_x = x*12+(xi-4);
+
+ if(y != 0 && y != 11)
+ {
+ res_y -= m_scrf;
+ if(res_y < 18) /* wrap-around */
+ res_y += 216;
+ }
+
+ if(pix != 0)
+ {
+ UINT8 r,g,b;
+
+ if(pix & 2)
+ {
+ r = (color & 0x1) ? 0xff : 0x00;
+ g = (color & 0x2) ? 0xff : 0x00;
+ b = (color & 0x4) ? 0xff : 0x00;
+ }
+ else //if(pix & 1)
+ {
+ /* TODO: is there a parameter for the border parameter? */
+ r = 0x00;
+ g = 0x00;
+ b = 0x00;
+ }
+
+ /* TODO: clean this up (also needs better testing) */
+ if(y_base == 0)
+ {
+ res_x *= (m_hsz1 + 1);
+ res_y *= (m_vsz1 + 1);
+
+ if(res_y > 215 || res_x > 288)
+ continue;
+
+ for(yh=0;yh<m_vsz1+1;yh++)
+ for(xh=0;xh<m_hsz1+1;xh++)
+ bitmap.pix32(res_y+yh,res_x+xh) = r << 16 | g << 8 | b;
+ }
+ else if(y_base == 11)
+ {
+ res_x *= (m_hsz3 + 1);
+ res_y += ((m_vsz2 * (y-1)) * 18) + 9 * m_vsz2;
+ res_y *= (m_vsz3 + 1);
+
+ if(res_y > 215 || res_x > 288)
+ continue;
+
+ for(yh=0;yh<m_vsz3+1;yh++)
+ for(xh=0;xh<m_hsz3+1;xh++)
+ bitmap.pix32(res_y+yh,res_x+xh) = r << 16 | g << 8 | b;
+ }
+ else
+ {
+ res_x *= (m_hsz2 + 1);
+ res_y *= (m_vsz2 + 1);
+
+ if(res_y > 215 || res_x > 288)
+ continue;
+
+ for(yh=0;yh<m_vsz2+1;yh++)
+ for(xh=0;xh<m_hsz2+1;xh++)
+ bitmap.pix32(res_y+yh,res_x+xh) = r << 16 | g << 8 | b;
+ }
+ }
+ }
+ }
+ }
+ }
+
+ return 0;
+}