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author Patrick Mackinlay <pmackinlay@hotmail.com>2023-05-25 12:03:17 +0700
committer Patrick Mackinlay <pmackinlay@hotmail.com>2023-05-25 12:03:17 +0700
commit2bfe504eefe62910fcdc3c560239465cb6796729 (patch)
tree820c70efd280e68bf271a3e8c947c00279652e1b /src
parentb458bf71c969d25aeef1ad52593d5af202b57875 (diff)
bt47x: add bt479 device
Diffstat (limited to 'src')
-rw-r--r--src/devices/video/bt47x.cpp185
-rw-r--r--src/devices/video/bt47x.h42
2 files changed, 203 insertions, 24 deletions
diff --git a/src/devices/video/bt47x.cpp b/src/devices/video/bt47x.cpp
index 24c78633228..6244dc53b8f 100644
--- a/src/devices/video/bt47x.cpp
+++ b/src/devices/video/bt47x.cpp
@@ -10,18 +10,19 @@
* Bt476 80Mhz 8 bit 3 6 bit
* Bt477 80MHz 8 bit 4 bit 3 8 bit sleep mode, compatibility mode
* Bt478 80MHz 8 bit 4 bit 3 8 bit
+ * Bt479 80MHz 8 bit 4 bit 3 8 bit 1024 palette entries, 16 windows, compatibility mode
*
* Not emulated:
*
* Bt473 80MHz 24 bit 4 bit 3 8 bit true color/passthrough/bypass modes
* Bt474 85MHz 4x8 bit 4x4 bit 3 8 bit sleep mode, vga mode
- * Bt479 80MHz 8 bit 4 bit 3 8 bit 16 windows, compatibility mode
*
* Sources:
- * - http://www.bitsavers.org/components/brooktree/_dataBooks/1991_Brooktree_Product_Databook.pdf
+ * - Brooktree Product Databook 1991
*
* TODO:
* - remaining devices
+ * - bt479 window mode, overlay mask, 10-bit modes
*/
#include "emu.h"
@@ -40,7 +41,7 @@ DEFINE_DEVICE_TYPE(BT475, bt475_device, "bt475", "Brooktree Bt475 256 Color RAMD
DEFINE_DEVICE_TYPE(BT476, bt476_device, "bt476", "Brooktree Bt476 256 Color RAMDAC")
DEFINE_DEVICE_TYPE(BT477, bt477_device, "bt477", "Brooktree Bt477 256 Color RAMDAC")
DEFINE_DEVICE_TYPE(BT478, bt478_device, "bt478", "Brooktree Bt478 256 Color RAMDAC")
-//DEFINE_DEVICE_TYPE(BT479, bt479_device, "bt479", "Brooktree Bt479 1024 Color RAMDAC")
+DEFINE_DEVICE_TYPE(BT479, bt479_device, "bt479", "Brooktree Bt479 1024 Color RAMDAC")
void bt47x_device_base::map(address_map &map)
{
@@ -57,6 +58,37 @@ void bt47x_device_base::map(address_map &map)
}
}
+u8 bt47x_device_base::read(offs_t offset)
+{
+ u8 data = 0;
+ switch (offset)
+ {
+ case 0: data = address_r(); break;
+ case 1: data = palette_r(); break;
+ case 2: data = mask_r(); break;
+ case 3: data = address_r(); break;
+ case 4: if (m_overlay_colors) data = address_r(); break;
+ case 5: if (m_overlay_colors) data = overlay_r(); break;
+ case 7: if (m_overlay_colors) data = address_r(); break;
+ }
+
+ return data;
+}
+
+void bt47x_device_base::write(offs_t offset, u8 data)
+{
+ switch (offset)
+ {
+ case 0: address_w(data); break;
+ case 1: palette_w(data); break;
+ case 2: mask_w(data); break;
+ case 3: address_w(data); break;
+ case 4: if (m_overlay_colors) address_w(data); break;
+ case 5: if (m_overlay_colors) overlay_w(data); break;
+ case 7: if (m_overlay_colors) address_w(data); break;
+ }
+}
+
void bt475_device_base::map(address_map &map)
{
bt47x_device_base::map(map);
@@ -64,6 +96,45 @@ void bt475_device_base::map(address_map &map)
map(0x06, 0x06).rw(FUNC(bt475_device_base::command_r), FUNC(bt475_device_base::command_w));
}
+u8 bt475_device_base::read(offs_t offset)
+{
+ if (offset == 6)
+ return command_r();
+ else
+ return bt47x_device_base::read(offset);
+}
+
+void bt475_device_base::write(offs_t offset, u8 data)
+{
+ if (offset == 6)
+ command_w(data);
+ else
+ bt47x_device_base::write(offset, data);
+}
+
+void bt479_device::map(address_map &map)
+{
+ bt47x_device_base::map(map);
+
+ map(0x06, 0x06).rw(FUNC(bt479_device::control_r), FUNC(bt479_device::control_w));
+}
+
+u8 bt479_device::read(offs_t offset)
+{
+ if (offset == 6)
+ return control_r();
+ else
+ return bt47x_device_base::read(offset);
+}
+
+void bt479_device::write(offs_t offset, u8 data)
+{
+ if (offset == 6)
+ control_w(data);
+ else
+ bt47x_device_base::write(offset, data);
+}
+
bt47x_device_base::bt47x_device_base(machine_config const &mconfig, device_type type, char const *tag, device_t *owner, u32 clock, unsigned const palette_colors, unsigned const overlay_colors, unsigned const color_bits)
: device_t(mconfig, type, tag, owner, clock)
, device_palette_interface(mconfig, *this)
@@ -103,6 +174,11 @@ bt478_device::bt478_device(machine_config const &mconfig, char const *tag, devic
{
}
+bt479_device::bt479_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock)
+ : bt47x_device_base(mconfig, BT479, tag, owner, clock, 1024, 16, 8)
+{
+}
+
void bt47x_device_base::device_start()
{
save_item(NAME(m_address));
@@ -121,6 +197,18 @@ void bt475_device_base::device_start()
save_item(NAME(m_command));
}
+void bt479_device::device_start()
+{
+ bt47x_device_base::device_start();
+
+ save_item(NAME(m_window));
+ save_item(NAME(m_command));
+ save_item(NAME(m_flood));
+
+ m_command[0] = 0;
+ m_command[1] = 0;
+}
+
u8 bt47x_device_base::address_r()
{
LOGMASKED(LOG_READS, "address_r 0x%02x\n", m_address);
@@ -139,22 +227,27 @@ void bt47x_device_base::address_w(u8 data)
m_address = data;
}
-void bt47x_device_base::increment_address(bool const side_effects)
+void bt47x_device_base::increment_address(bool const rgb, bool const side_effects)
{
if (!machine().side_effects_disabled() || side_effects)
{
- // increment component index and address register
- m_address_rgb = (m_address_rgb + 1) % 3;
- if (m_address_rgb == 0)
+ if (rgb)
+ {
+ // increment component index and address register
+ m_address_rgb = (m_address_rgb + 1) % 3;
+ if (m_address_rgb == 0)
+ m_address++;
+ }
+ else
m_address++;
}
}
u8 bt47x_device_base::palette_r()
{
- u8 const data = m_color_ram[m_address][m_address_rgb];
+ u8 const data = m_color_ram[address()][m_address_rgb];
- increment_address();
+ increment_address(true);
LOGMASKED(LOG_READS, "palette_r 0x%02x\n", data);
@@ -165,16 +258,16 @@ void bt47x_device_base::palette_w(u8 data)
{
LOG("palette_w 0x%02x\n", data);
- m_color_ram[m_address][m_address_rgb] = data;
+ m_color_ram[address()][m_address_rgb] = data;
// update the mame palette to match the device
if (m_address_rgb == 2)
- set_pen_color(m_address, rgb_t(
- m_color_ram[m_address][0] << (8 - color_bits()),
- m_color_ram[m_address][1] << (8 - color_bits()),
- m_color_ram[m_address][2] << (8 - color_bits())));
+ set_pen_color(address(), rgb_t(
+ m_color_ram[address()][0] << (8 - color_bits()),
+ m_color_ram[address()][1] << (8 - color_bits()),
+ m_color_ram[address()][2] << (8 - color_bits())));
- increment_address(true);
+ increment_address(true, true);
}
u8 bt47x_device_base::mask_r()
@@ -196,7 +289,7 @@ u8 bt47x_device_base::overlay_r()
unsigned const index = m_palette_colors + (m_address & (m_overlay_colors - 1));
u8 const data = m_color_ram[index][m_address_rgb];
- increment_address();
+ increment_address(true);
LOGMASKED(LOG_READS, "overlay_r 0x%02x\n", data);
@@ -217,7 +310,7 @@ void bt47x_device_base::overlay_w(u8 data)
m_color_ram[index][1] << (8 - color_bits()),
m_color_ram[index][2] << (8 - color_bits())));
- increment_address(true);
+ increment_address(true, true);
}
u8 bt475_device_base::command_r()
@@ -233,3 +326,61 @@ void bt475_device_base::command_w(u8 data)
m_command = data;
}
+
+enum bt479_command_0_mask : u8
+{
+ BT479_CR0_OL = 0x0f, // overlay read mask
+ BT479_CR0_CP = 0xf0, // color palette select
+};
+
+u8 bt479_device::control_r()
+{
+ unsigned const address = bt47x_device_base::address();
+ u8 data = 0;
+
+ switch (address)
+ {
+ case 0x82:
+ case 0x83:
+ data = m_command[address & 1];
+ break;
+ case 0x84:
+ case 0x85:
+ data = m_flood[address & 1];
+ break;
+ default:
+ if (address < 0x80)
+ data = m_window[address];
+ break;
+ }
+
+ LOGMASKED(LOG_READS, "control_r 0x%02x\n", data);
+ increment_address(false);
+ return data;
+}
+
+void bt479_device::control_w(u8 data)
+{
+ unsigned const address = bt47x_device_base::address();
+ LOG("control_w address 0x%02x data 0x%02x\n", address, data);
+
+ switch (address)
+ {
+ case 0x82:
+ case 0x83:
+ LOG("control_w command%d 0x%02x\n", address & 1, data);
+ m_command[address & 1] = data;
+ break;
+ case 0x84:
+ case 0x85:
+ LOG("control_w flood%d 0x%02x\n", address & 1, data);
+ m_flood[address & 1] = data;
+ break;
+ default:
+ if (address < 0x80)
+ m_window[address] = data;
+ break;
+ }
+
+ increment_address(false, true);
+}
diff --git a/src/devices/video/bt47x.h b/src/devices/video/bt47x.h
index a51fe2c3df8..4248ff20ebe 100644
--- a/src/devices/video/bt47x.h
+++ b/src/devices/video/bt47x.h
@@ -15,14 +15,16 @@ public:
rgb_t overlay_lookup(u8 index) const { return pen_color(m_palette_colors + index); }
virtual void map(address_map &map);
+ virtual u8 read(offs_t offset);
+ virtual void write(offs_t offset, u8 data);
protected:
bt47x_device_base(machine_config const &mconfig, device_type type, char const *tag, device_t *owner, u32 clock, unsigned const palette_colors, unsigned const overlay_colors, unsigned const color_bits);
- // device_t overrides
+ // device_t implementation
virtual void device_start() override;
- // device_palette_interface overrides
+ // device_palette_interface implementation
virtual u32 palette_entries() const noexcept override { return m_palette_colors + m_overlay_colors; }
// read/write handlers
@@ -35,12 +37,12 @@ protected:
u8 overlay_r();
void overlay_w(u8 data);
+ // helpers
+ virtual unsigned address() const { return m_address; };
+ void increment_address(bool const rgb, bool const side_effects = false);
virtual unsigned color_bits() const { return m_color_bits; }
private:
- // helpers
- void increment_address(bool const side_effects = false);
-
// device state
u8 m_address;
u8 m_address_rgb;
@@ -58,11 +60,13 @@ class bt475_device_base : public bt47x_device_base
{
public:
virtual void map(address_map &map) override;
+ virtual u8 read(offs_t offset) override;
+ virtual void write(offs_t offset, u8 data) override;
protected:
bt475_device_base(machine_config const &mconfig, device_type type, char const *tag, device_t *owner, u32 clock, unsigned const palette_colors, unsigned const overlay_colors, unsigned const color_bits);
- // device_t overrides
+ // device_t implementation
virtual void device_start() override;
u8 command_r();
@@ -115,6 +119,30 @@ public:
bt478_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock);
};
+class bt479_device : public bt47x_device_base
+{
+public:
+ bt479_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock);
+
+ virtual void map(address_map &map) override;
+ virtual u8 read(offs_t offset) override;
+ virtual void write(offs_t offset, u8 data) override;
+
+protected:
+ virtual void device_start() override;
+
+ virtual unsigned address() const override { return BIT(m_command[0], 4, 2) * 0x100 + bt47x_device_base::address(); };
+ virtual unsigned color_bits() const override { return BIT(m_command[1], 1) ? 8 : 6; }
+
+ u8 control_r();
+ void control_w(u8 data);
+
+private:
+ u8 m_window[0x80];
+ u8 m_command[2];
+ u8 m_flood[2];
+};
+
DECLARE_DEVICE_TYPE(BT471, bt471_device)
//DECLARE_DEVICE_TYPE(BT473, bt473_device)
//DECLARE_DEVICE_TYPE(BT474, bt474_device)
@@ -122,6 +150,6 @@ DECLARE_DEVICE_TYPE(BT475, bt475_device)
DECLARE_DEVICE_TYPE(BT476, bt476_device)
DECLARE_DEVICE_TYPE(BT477, bt477_device)
DECLARE_DEVICE_TYPE(BT478, bt478_device)
-//DECLARE_DEVICE_TYPE(BT479, bt479_device)
+DECLARE_DEVICE_TYPE(BT479, bt479_device)
#endif // MAME_VIDEO_BT47X_H