// license:BSD-3-Clause
// copyright-holders:Ville Linde
// Konami 0000057714 "GCU" 2D Graphics Chip
#include "emu.h"
#include "k057714.h"
#include "screen.h"
#define DUMP_VRAM 0
#define PRINT_GCU 0
#define PRINT_CMD_EXEC 0
DEFINE_DEVICE_TYPE(K057714, k057714_device, "k057714", "k057714_device GCU")
k057714_device::k057714_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, K057714, tag, owner, clock)
, m_irq(*this)
{
}
void k057714_device::device_start()
{
m_irq.resolve_safe();
m_vram = std::make_unique<uint32_t[]>(0x2000000/4);
memset(m_vram.get(), 0, 0x2000000);
}
void k057714_device::device_reset()
{
m_vram_read_addr = 0;
m_command_fifo0_ptr = 0;
m_command_fifo1_ptr = 0;
m_vram_fifo0_addr = 0;
m_vram_fifo1_addr = 0;
m_fb_origin_x = 0;
m_fb_origin_y = 0;
for (auto & elem : m_frame)
{
elem.base = 0;
elem.width = 0;
elem.height = 0;
}
}
void k057714_device::device_stop()
{
#if DUMP_VRAM
char filename[200];
sprintf(filename, "%s_vram.bin", basetag());
printf("dumping %s\n", filename);
FILE *file = fopen(filename, "wb");
int i;
for (i=0; i < 0x2000000/4; i++)
{
fputc((m_vram[i] >> 24) & 0xff, file);
fputc((m_vram[i] >> 16) & 0xff, file);
fputc((m_vram[i] >> 8) & 0xff, file);
fputc((m_vram[i] >> 0) & 0xff, file);
}
fclose(file);
#endif
}
READ32_MEMBER(k057714_device::read)
{
int reg = offset * 4;
// VRAM Read
if (reg >= 0x80 && reg < 0x100)
{
return m_vram[m_vram_read_addr + offset - 0x20];
}
switch (reg)
{
case 0x78: // GCU Status
/* ppd checks bits 0x0041 of the upper halfword on interrupt */
return 0xffff0005;
default:
break;
}
return 0xffffffff;
}
WRITE32_MEMBER(k057714_device::write)
{
int reg = offset * 4;
switch (reg)
{
case 0x10:
/* IRQ clear/enable; ppd writes bit off then on in response to interrupt */
/* it enables bits 0x41, but 0x01 seems to be the one it cares about */
if (ACCESSING_BITS_16_31 && (data & 0x00010000) == 0)
{
if (!m_irq.isnull())
{
m_irq(CLEAR_LINE);
}
}
if (ACCESSING_BITS_0_15)
{
m_layer_select = data;
#if PRINT_GCU
printf("%s_w: %02X, %08X, %08X\n", basetag(), reg, data, mem_mask);
#endif
}
break;
case 0x14: // ?
break;
case 0x18: // ?
break;
case 0x1c: // set to 1 on "media bus" access
if ((data >> 16) == 1)
{
m_ext_fifo_count = 0;
m_ext_fifo_line = 0;
}
break;
case 0x20: // Framebuffer 0 Origin(?)
if (ACCESSING_BITS_16_31)
m_frame[0].y = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[0].x = data & 0xffff;
break;
case 0x24: // Framebuffer 1 Origin(?)
if (ACCESSING_BITS_16_31)
m_frame[1].y = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[1].x = data & 0xffff;
break;
case 0x28: // Framebuffer 2 Origin(?)
if (ACCESSING_BITS_16_31)
m_frame[2].y = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[2].x = data & 0xffff;
break;
case 0x2c: // Framebuffer 3 Origin(?)
if (ACCESSING_BITS_16_31)
m_frame[3].y = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[3].x = data & 0xffff;
break;
case 0x30: // Framebuffer 0 Dimensions
if (ACCESSING_BITS_16_31)
m_frame[0].height = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[0].width = data & 0xffff;
#if PRINT_GCU
printf("%s FB0 Dimensions: W %04X, H %04X\n", basetag(), data & 0xffff, (data >> 16) & 0xffff);
#endif
break;
case 0x34: // Framebuffer 1 Dimensions
if (ACCESSING_BITS_16_31)
m_frame[1].height = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[1].width = data & 0xffff;
#if PRINT_GCU
printf("%s FB1 Dimensions: W %04X, H %04X\n", basetag(), data & 0xffff, (data >> 16) & 0xffff);
#endif
break;
case 0x38: // Framebuffer 2 Dimensions
if (ACCESSING_BITS_16_31)
m_frame[2].height = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[2].width = data & 0xffff;
#if PRINT_GCU
printf("%s FB2 Dimensions: W %04X, H %04X\n", basetag(), data & 0xffff, (data >> 16) & 0xffff);
#endif
break;
case 0x3c: // Framebuffer 3 Dimensions
if (ACCESSING_BITS_16_31)
m_frame[3].height = (data >> 16) & 0xffff;
if (ACCESSING_BITS_0_15)
m_frame[3].width = data & 0xffff;
#if PRINT_GCU
printf("%s FB3 Dimensions: W %04X, H %04X\n", basetag(), data & 0xffff, (data >> 16) & 0xffff);
#endif
break;
case 0x40: // Framebuffer 0 Base
m_frame[0].base = data;
#if PRINT_GCU
printf("%s FB0 Base: %08X\n", basetag(), data);
#endif
break;
case 0x44: // Framebuffer 1 Base
m_frame[1].base = data;
#if PRINT_GCU
printf("%s FB1 Base: %08X\n", basetag(), data);
#endif
break;
case 0x48: // Framebuffer 2 Base
m_frame[2].base = data;
#if PRINT_GCU
printf("%s FB2 Base: %08X\n", basetag(), data);
#endif
break;
case 0x4c: // Framebuffer 3 Base
m_frame[3].base = data;
#if PRINT_GCU
printf("%s FB3 Base: %08X\n", basetag(), data);
#endif
break;
case 0x54:
if (ACCESSING_BITS_16_31)
m_ext_fifo_num_lines = data >> 16;
if (ACCESSING_BITS_0_15)
m_ext_fifo_width = data & 0xffff;
break;
case 0x58:
m_ext_fifo_addr = (data & 0xffffff);
break;
case 0x5c: // VRAM Read Address
m_vram_read_addr = (data & 0xffffff) / 2;
break;
case 0x60: // VRAM Port 0 Write Address
m_vram_fifo0_addr = (data & 0xffffff) / 2;
break;
case 0x68: // VRAM Port 0/1 Mode
if (ACCESSING_BITS_16_31)
m_vram_fifo0_mode = data >> 16;
if (ACCESSING_BITS_0_15)
m_vram_fifo1_mode = data & 0xffff;
break;
case 0x70: // VRAM Port 0 Write FIFO
if (m_vram_fifo0_mode & 0x100)
{
// write to command fifo
m_command_fifo0[m_command_fifo0_ptr] = data;
m_command_fifo0_ptr++;
// execute when filled
if (m_command_fifo0_ptr >= 4)
{
//printf("GCU FIFO0 exec: %08X %08X %08X %08X\n", m_command_fifo0[0], m_command_fifo0[1], m_command_fifo0[2], m_command_fifo0[3]);
execute_command(m_command_fifo0);
m_command_fifo0_ptr = 0;
}
}
else
{
// write to VRAM fifo
m_vram[m_vram_fifo0_addr] = data;
m_vram_fifo0_addr++;
}
break;
case 0x64: // VRAM Port 1 Write Address
m_vram_fifo1_addr = (data & 0xffffff) / 2;
break;
case 0x74: // VRAM Port 1 Write FIFO
if (m_vram_fifo1_mode & 0x100)
{
// write to command fifo
m_command_fifo1[m_command_fifo1_ptr] = data;
m_command_fifo1_ptr++;
// execute when filled
if (m_command_fifo1_ptr >= 4)
{
//printf("GCU FIFO1 exec: %08X %08X %08X %08X\n", m_command_fifo1[0], m_command_fifo1[1], m_command_fifo1[2], m_command_fifo1[3]);
execute_command(m_command_fifo1);
m_command_fifo1_ptr = 0;
}
}
else
{
// write to VRAM fifo
m_vram[m_vram_fifo1_addr] = data;
m_vram_fifo1_addr++;
}
break;
case 0x6c:
if (ACCESSING_BITS_0_15)
{
m_reg_6c = data & 0xffff;
}
break;
default:
//printf("%s_w: %02X, %08X, %08X\n", basetag(), reg, data, mem_mask);
break;
}
}
WRITE32_MEMBER(k057714_device::fifo_w)
{
if (ACCESSING_BITS_16_31)
{
if (m_ext_fifo_count != 0) // first access is a dummy write
{
int count = m_ext_fifo_count - 1;
uint32_t addr = (((m_ext_fifo_addr >> 10) + m_ext_fifo_line) * 1024) + count;
if ((count & 1) == 0)
{
m_vram[addr >> 1] &= 0x0000ffff;
m_vram[addr >> 1] |= (data & 0xffff0000);
}
else
{
m_vram[addr >> 1] &= 0xffff0000;
m_vram[addr >> 1] |= (data >> 16);
}
}
m_ext_fifo_count++;
if (m_ext_fifo_count > m_ext_fifo_width+1)
{
m_ext_fifo_line++;
m_ext_fifo_count = 0;
}
}
}
void k057714_device::draw_frame(int frame, bitmap_ind16 &bitmap, const rectangle &cliprect, bool inverse_trans)
{
int height = m_frame[frame].height;
int width = m_frame[frame].width;
if (width == 0 || height == 0)
return;
uint16_t *vram16 = (uint16_t*)m_vram.get();
int fb_pitch = 1024;
uint16_t trans_value = inverse_trans ? 0x8000 : 0x0000;
if (m_frame[frame].y + height > cliprect.max_y)
height = cliprect.max_y - m_frame[frame].y;
if (m_frame[frame].x + width > cliprect.max_x)
width = cliprect.max_x - m_frame[frame].x;
for (int j = 0; j < height; j++)
{
uint16_t *d = &bitmap.pix16(j + m_frame[frame].y, m_frame[frame].x);
int li = (j * fb_pitch);
for (int i = 0; i < width; i++)
{
uint16_t pix = vram16[(m_frame[frame].base + li + i) ^ NATIVE_ENDIAN_VALUE_LE_BE(1, 0)];
if ((pix & 0x8000) != trans_value) {
d[i] = pix & 0x7fff;
}
}
}
}
int k057714_device::draw(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
int width = m_frame[0].width;
int height = m_frame[0].height;
if (width != 0 && height != 0)
{
rectangle visarea = screen.visible_area();
if ((visarea.max_x+1) != width || (visarea.max_y+1) != height)
{
visarea.max_x = width-1;
visarea.max_y = height-1;
screen.configure(width, height, visarea, screen.frame_period().attoseconds());
}
}
bitmap.fill(0, cliprect);
bool inverse_trans = false;
// most likely wrong, inverse transparency is only used by kbm
if ((m_reg_6c & 0xf) != 0)
inverse_trans = true;
draw_frame((m_layer_select >> 8) & 3, bitmap, cliprect, inverse_trans);
draw_frame((m_layer_select >> 10) & 3, bitmap, cliprect, inverse_trans);
draw_frame((m_layer_select >> 12) & 3, bitmap, cliprect, inverse_trans);
draw_frame((m_layer_select >> 14) & 3, bitmap, cliprect, inverse_trans);
return 0;
}
void k057714_device::draw_object(uint32_t *cmd)
{
// 0x00: xxx----- -------- -------- -------- command (5)
// 0x00: ---x---- -------- -------- -------- 0: absolute coordinates
// 1: relative coordinates from framebuffer origin
// 0x00: ----xx-- -------- -------- -------- ?
// 0x00: -------- xxxxxxxx xxxxxxxx xxxxxxxx object data address in vram
// 0x01: -------- -------- ------xx xxxxxxxx object x
// 0x01: -------- xxxxxxxx xxxxxx-- -------- object y
// 0x01: -----x-- -------- -------- -------- object x flip
// 0x01: ----x--- -------- -------- -------- object y flip
// 0x01: --xx---- -------- -------- -------- object alpha enable (different blend modes?)
// 0x01: -x------ -------- -------- -------- object transparency enable (?)
// 0x01: x------- -------- -------- -------- inverse transparency? (used by kbm)
// 0x02: -------- -------- ------xx xxxxxxxx object width
// 0x02: -------- -----xxx xxxxxx-- -------- object x scale
// 0x02: xxxxx--- -------- -------- -------- ?
// 0x02: -----xxx xx------ -------- -------- translucency
// 0x02: -------- --xxx--- -------- -------- ?
// 0x03: -------- -------- ------xx xxxxxxxx object height
// 0x03: -------- -----xxx xxxxxx-- -------- object y scale
// 0x03: xxxxx--- -------- -------- -------- ?
// 0x03: -----xxx xx------ -------- -------- ?
// 0x03: -------- --xxx--- -------- -------- ?
int x = cmd[1] & 0x3ff;
int y = (cmd[1] >> 10) & 0x3fff;
int width = (cmd[2] & 0x3ff) + 1;
int height = (cmd[3] & 0x3ff) + 1;
int xscale = (cmd[2] >> 10) & 0x1ff;
int yscale = (cmd[3] >> 10) & 0x1ff;
bool xflip = (cmd[1] & 0x04000000) ? true : false;
bool yflip = (cmd[1] & 0x08000000) ? true : false;
bool alpha_enable = (cmd[1] & 0x30000000) ? true : false;
bool trans_enable = (cmd[1] & 0xc0000000) ? true : false;
uint32_t address = cmd[0] & 0xffffff;
int alpha_level = (cmd[2] >> 22) & 0x1f;
bool relative_coords = (cmd[0] & 0x10000000) ? true : false;
uint16_t trans_value = (cmd[1] & 0x80000000) ? 0x0000 : 0x8000;
if (relative_coords)
{
x += m_fb_origin_x;
y += m_fb_origin_y;
}
uint16_t *vram16 = (uint16_t*)m_vram.get();
if (xscale == 0 || yscale == 0)
{
return;
}
#if PRINT_CMD_EXEC
printf("%s Draw Object %08X, x %d, y %d, w %d, h %d, sx: %f, sy: %f [%08X %08X %08X %08X]\n", basetag(), address, x, y, width, height, (float)(xscale) / 64.0f, (float)(yscale) / 64.0f, cmd[0], cmd[1], cmd[2], cmd[3]);
#endif
width = (((width * 65536) / xscale) * 64) / 65536;
height = (((height * 65536) / yscale) * 64) / 65536;
int fb_width = m_frame[0].width;
int fb_height = m_frame[0].height;
if (width > fb_width)
width = fb_width;
if (height > fb_height)
height = fb_height;
int fb_pitch = 1024;
int v = 0;
for (int j=0; j < height; j++)
{
int index;
int xinc;
uint32_t fbaddr = ((j+y) * fb_pitch) + x;
if (yflip)
{
index = address + ((height - 1 - (v >> 6)) * 1024);
}
else
{
index = address + ((v >> 6) * 1024);
}
if (xflip)
{
fbaddr += width;
xinc = -1;
}
else
{
xinc = 1;
}
int u = 0;
for (int i=0; i < width; i++)
{
uint16_t pix = vram16[((index + (u >> 6)) ^ NATIVE_ENDIAN_VALUE_LE_BE(1,0)) & 0xffffff];
bool draw = !trans_enable || (trans_enable && ((pix & 0x8000) == trans_value));
if (alpha_enable)
{
if (draw)
{
if ((pix & 0x7fff) != 0)
{
uint16_t srcpix = vram16[fbaddr ^ NATIVE_ENDIAN_VALUE_LE_BE(1,0)];
uint32_t sr = (srcpix >> 10) & 0x1f;
uint32_t sg = (srcpix >> 5) & 0x1f;
uint32_t sb = (srcpix >> 0) & 0x1f;
uint32_t r = (pix >> 10) & 0x1f;
uint32_t g = (pix >> 5) & 0x1f;
uint32_t b = (pix >> 0) & 0x1f;
sr += (r * alpha_level) >> 4;
sg += (g * alpha_level) >> 4;
sb += (b * alpha_level) >> 4;
if (sr > 0x1f) sr = 0x1f;
if (sg > 0x1f) sg = 0x1f;
if (sb > 0x1f) sb = 0x1f;
vram16[fbaddr ^ NATIVE_ENDIAN_VALUE_LE_BE(1,0)] = (sr << 10) | (sg << 5) | sb | (pix & 0x8000);
}
}
}
else
{
if (draw)
{
vram16[fbaddr ^ NATIVE_ENDIAN_VALUE_LE_BE(1,0)] = (pix & 0xffff);
}
}
fbaddr += xinc;
u += xscale;
}
v += yscale;
}
}
void k057714_device::fill_rect(uint32_t *cmd)
{
// 0x00: xxx----- -------- -------- -------- command (4)
// 0x00: ---x---- -------- -------- -------- 0: absolute coordinates
// 1: relative coordinates from framebuffer origin
// 0x00: ----xx-- -------- -------- -------- ?
// 0x00: -------- -------- ------xx xxxxxxxx width
// 0x00: -------- ----xxxx xxxxxx-- -------- height
// 0x01: -------- -------- ------xx xxxxxxxx x
// 0x01: -------- xxxxxxxx xxxxxx-- -------- y
// 0x01: ---x---- -------- -------- -------- ?
// 0x02: xxxxxxxx xxxxxxxx -------- -------- fill pattern pixel 0
// 0x02: -------- -------- xxxxxxxx xxxxxxxx fill pattern pixel 1
// 0x03: xxxxxxxx xxxxxxxx -------- -------- fill pattern pixel 2
// 0x03: -------- -------- xxxxxxxx xxxxxxxx fill pattern pixel 3
int x = cmd[1] & 0x3ff;
int y = (cmd[1] >> 10) & 0x3fff;
int width = (cmd[0] & 0x3ff) + 1;
int height = ((cmd[0] >> 10) & 0x3ff) + 1;
bool relative_coords = (cmd[0] & 0x10000000) ? true : false;
if (relative_coords)
{
x += m_fb_origin_x;
y += m_fb_origin_y;
}
uint16_t color[4];
color[0] = (cmd[2] >> 16);
color[1] = (cmd[2] & 0xffff);
color[2] = (cmd[3] >> 16);
color[3] = (cmd[3] & 0xffff);
#if PRINT_CMD_EXEC
printf("%s Fill Rect x %d, y %d, w %d, h %d, %08X %08X [%08X %08X %08X %08X]\n", basetag(), x, y, width, height, cmd[2], cmd[3], cmd[0], cmd[1], cmd[2], cmd[3]);
#endif
int x1 = x;
int x2 = x + width;
int y1 = y;
int y2 = y + height;
uint16_t *vram16 = (uint16_t*)m_vram.get();
int fb_pitch = 1024;
for (int j=y1; j < y2; j++)
{
uint32_t fbaddr = j * fb_pitch;
for (int i=x1; i < x2; i++)
{
vram16[(fbaddr+i) ^ NATIVE_ENDIAN_VALUE_LE_BE(1,0)] = color[i&3];
}
}
}
void k057714_device::draw_character(uint32_t *cmd)
{
// 0x00: xxx----- -------- -------- -------- command (7)
// 0x00: ---x---- -------- -------- -------- 0: absolute coordinates
// 1: relative coordinates from framebuffer base (unverified, should be same as other operations)
// 0x00: -------- xxxxxxxx xxxxxxxx xxxxxxxx character data address in vram
// 0x01: -------- -------- ------xx xxxxxxxx character x
// 0x01: -------- xxxxxxxx xxxxxx-- -------- character y
// 0x01: -------x -------- -------- -------- double height
// 0x01: --x----- -------- -------- -------- ?
// 0x01: -x------ -------- -------- -------- transparency enable
// 0x02: xxxxxxxx xxxxxxxx -------- -------- color 0
// 0x02: -------- -------- xxxxxxxx xxxxxxxx color 1
// 0x03: xxxxxxxx xxxxxxxx -------- -------- color 2
// 0x03: -------- -------- xxxxxxxx xxxxxxxx color 3
int x = cmd[1] & 0x3ff;
int y = (cmd[1] >> 10) & 0x3fff;
uint32_t address = cmd[0] & 0xffffff;
uint16_t color[4];
bool relative_coords = (cmd[0] & 0x10000000) ? true : false;
bool double_height = (cmd[1] & 0x01000000) ? true : false;
bool trans_enable = (cmd[1] & 0x40000000) ? true : false;
if (relative_coords)
{
x += m_fb_origin_x;
y += m_fb_origin_y;
}
color[0] = cmd[2] >> 16;
color[1] = cmd[2] & 0xffff;
color[2] = cmd[3] >> 16;
color[3] = cmd[3] & 0xffff;
#if PRINT_CMD_EXEC
printf("%s Draw Char %08X, x %d, y %d [%08X %08X %08X %08X]\n", basetag(), address, x, y, cmd[0], cmd[1], cmd[2], cmd[3]);
#endif
uint16_t *vram16 = (uint16_t*)m_vram.get();
int fb_pitch = 1024;
int height = double_height ? 16 : 8;
for (int j=0; j < height; j++)
{
uint32_t fbaddr = (y+j) * fb_pitch;
uint16_t line = vram16[address ^ NATIVE_ENDIAN_VALUE_LE_BE(1,0)];
address += 4;
for (int i=0; i < 8; i++)
{
int p = (line >> ((7-i) * 2)) & 3;
bool draw = !trans_enable || (trans_enable && (color[p] & 0x8000));
if (draw)
vram16[(fbaddr+x+i) ^ NATIVE_ENDIAN_VALUE_LE_BE(1,0)] = color[p];
}
}
}
void k057714_device::fb_config(uint32_t *cmd)
{
// 0x00: xxx----- -------- -------- -------- command (3)
// 0x01: -------- -------- -------- -------- unused?
// 0x02: -------- -------- ------xx xxxxxxxx Framebuffer Origin X
// 0x03: -------- -------- --xxxxxx xxxxxxxx Framebuffer Origin Y
#if PRINT_CMD_EXEC
printf("%s FB Config %08X %08X %08X %08X\n", basetag(), cmd[0], cmd[1], cmd[2], cmd[3]);
#endif
m_fb_origin_x = cmd[2] & 0x3ff;
m_fb_origin_y = cmd[3] & 0x3fff;
}
void k057714_device::execute_display_list(uint32_t addr)
{
bool end = false;
int counter = 0;
#if PRINT_CMD_EXEC
printf("%s Exec Display List %08X\n", basetag(), addr);
#endif
addr /= 2;
while (!end && counter < 0x1000 && addr < (0x2000000/4))
{
uint32_t *cmd = &m_vram[addr];
addr += 4;
int command = (cmd[0] >> 29) & 0x7;
switch (command)
{
case 0: // NOP?
break;
case 1: // Execute display list
execute_display_list(cmd[0] & 0xffffff);
break;
case 2: // End of display list
end = true;
break;
case 3: // Framebuffer config
fb_config(cmd);
break;
case 4: // Fill rectangle
fill_rect(cmd);
break;
case 5: // Draw object
draw_object(cmd);
break;
case 6:
case 7: // Draw 8x8 character (2 bits per pixel)
draw_character(cmd);
break;
default:
printf("GCU Unknown command %08X %08X %08X %08X\n", cmd[0], cmd[1], cmd[2], cmd[3]);
break;
}
counter++;
};
}
void k057714_device::execute_command(uint32_t* cmd)
{
int command = (cmd[0] >> 29) & 0x7;
#if PRINT_CMD_EXEC
printf("%s Exec Command %08X, %08X, %08X, %08X\n", basetag(), cmd[0], cmd[1], cmd[2], cmd[3]);
#endif
switch (command)
{
case 0: // NOP?
break;
case 1: // Execute display list
execute_display_list(cmd[0] & 0xffffff);
break;
case 2: // End of display list
break;
case 3: // Framebuffer config
fb_config(cmd);
break;
case 4: // Fill rectangle
fill_rect(cmd);
break;
case 5: // Draw object
draw_object(cmd);
break;
case 6:
case 7: // Draw 8x8 character (2 bits per pixel)
draw_character(cmd);
break;
default:
printf("GCU Unknown command %08X %08X %08X %08X\n", cmd[0], cmd[1], cmd[2], cmd[3]);
break;
}
}