// license:BSD-3-Clause // copyright-holders:Patrick Mackinlay /* * An emulation of the Brooktree Bt47x family of RAMDAC devices. * * Max. Input Output * Part Clock Color Overlay Num. Levels Other * Bt471 80MHz 8 bit 4 bit 3 6 bit * Bt475 80MHz 8 bit 4 bit 3 6 bit sleep mode, compatibility mode * 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 * * 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 * * TODO: * - remaining devices */ #include "emu.h" #include "bt47x.h" #define LOG_GENERAL (1U << 0) #define LOG_READS (1U << 1) //#define VERBOSE (LOG_GENERAL) #include "logmacro.h" DEFINE_DEVICE_TYPE(BT471, bt471_device, "bt471", "Brooktree Bt471 256 Color RAMDAC") //DEFINE_DEVICE_TYPE(BT473, bt473_device, "bt473", "Brooktree Bt473 True-Color RAMDAC") //DEFINE_DEVICE_TYPE(BT474, bt474_device, "bt474", "Brooktree Bt474 256 Color RAMDAC") DEFINE_DEVICE_TYPE(BT475, bt475_device, "bt475", "Brooktree Bt475 256 Color RAMDAC") 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") void bt47x_device_base::map(address_map &map) { map(0x00, 0x00).rw(FUNC(bt47x_device_base::address_r), FUNC(bt47x_device_base::address_w)); map(0x01, 0x01).rw(FUNC(bt47x_device_base::palette_r), FUNC(bt47x_device_base::palette_w)); map(0x02, 0x02).rw(FUNC(bt47x_device_base::mask_r), FUNC(bt47x_device_base::mask_w)); map(0x03, 0x03).rw(FUNC(bt47x_device_base::address_r), FUNC(bt47x_device_base::address_w)); if (m_overlay_colors) { map(0x04, 0x04).rw(FUNC(bt47x_device_base::address_r), FUNC(bt47x_device_base::address_w)); map(0x05, 0x05).rw(FUNC(bt47x_device_base::overlay_r), FUNC(bt47x_device_base::overlay_w)); map(0x07, 0x07).rw(FUNC(bt47x_device_base::address_r), FUNC(bt47x_device_base::address_w)); } } void bt475_device_base::map(address_map &map) { bt47x_device_base::map(map); map(0x06, 0x06).rw(FUNC(bt475_device_base::command_r), FUNC(bt475_device_base::command_w)); } 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) , m_palette_colors(palette_colors) , m_overlay_colors(overlay_colors) , m_color_bits(color_bits) { } bt475_device_base::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) : bt47x_device_base(mconfig, type, tag, owner, clock, palette_colors, overlay_colors, color_bits) { } bt471_device::bt471_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock) : bt47x_device_base(mconfig, BT471, tag, owner, clock, 256, 16, 6) { } bt475_device::bt475_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock) : bt475_device_base(mconfig, BT475, tag, owner, clock, 256, 16, 6) { } bt476_device::bt476_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock) : bt47x_device_base(mconfig, BT476, tag, owner, clock, 256, 0, 6) { } bt477_device::bt477_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock) : bt475_device_base(mconfig, BT477, tag, owner, clock, 256, 16, 8) { } bt478_device::bt478_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock) : bt47x_device_base(mconfig, BT478, tag, owner, clock, 256, 16, 8) { } void bt47x_device_base::device_start() { save_item(NAME(m_address)); save_item(NAME(m_address_rgb)); save_item(NAME(m_read_mask)); m_color_ram = std::make_unique[]>(m_palette_colors + m_overlay_colors); save_pointer(NAME(m_color_ram), m_palette_colors + m_overlay_colors); } void bt475_device_base::device_start() { bt47x_device_base::device_start(); save_item(NAME(m_command)); } u8 bt47x_device_base::address_r() { LOGMASKED(LOG_READS, "address_r 0x%02x\n", m_address); if (!machine().side_effects_disabled()) m_address_rgb = 0; return m_address; } void bt47x_device_base::address_w(u8 data) { LOG("address_w 0x%02x\n", data); m_address_rgb = 0; m_address = data; } void bt47x_device_base::increment_address(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) m_address++; } } u8 bt47x_device_base::palette_r() { u8 const data = m_color_ram[m_address][m_address_rgb]; increment_address(); LOGMASKED(LOG_READS, "palette_r 0x%02x\n", data); return data; } void bt47x_device_base::palette_w(u8 data) { LOG("palette_w 0x%02x\n", data); m_color_ram[m_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()))); increment_address(true); } u8 bt47x_device_base::mask_r() { LOGMASKED(LOG_READS, "mask_r 0x%02x\n", m_read_mask); return m_read_mask; } void bt47x_device_base::mask_w(u8 data) { LOG("mask_w 0x%02x\n", data); m_read_mask = data; } 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(); LOGMASKED(LOG_READS, "overlay_r 0x%02x\n", data); return data; } void bt47x_device_base::overlay_w(u8 data) { LOG("overlay_w 0x%02x\n", data); unsigned const index = m_palette_colors + (m_address & (m_overlay_colors - 1)); m_color_ram[index][m_address_rgb] = data; // update the mame palette to match the device if (m_address_rgb == 2) set_pen_color(index, rgb_t( m_color_ram[index][0] << (8 - color_bits()), m_color_ram[index][1] << (8 - color_bits()), m_color_ram[index][2] << (8 - color_bits()))); increment_address(true); } u8 bt475_device_base::command_r() { LOGMASKED(LOG_READS, "command_r 0x%02x\n", m_command); return m_command; } void bt475_device_base::command_w(u8 data) { LOG("command_w 0x%02x\n", data); m_command = data; }