Rivoreo Source Code Repositories
src.rivoreo.one / emulators / v86 / f23ff606fc0e86a0a8b003ce9a7e3d3344c9aa53 / . / src / vga.js
blob: a02f48ff3c6d8c26fc3886230fee40114c70e8c6 [file] [log] [blame] [raw]
"use strict";
var
/**
* Always 64k
* @const
*/
VGA_BANK_SIZE = 64 * 1024,
/** @const */
MAX_XRES = 2560,
/** @const */
MAX_YRES = 1600,
/** @const */
MAX_BPP = 32;
/** @const */
//var VGA_LFB_ADDRESS = 0xFE000000; // set by seabios
var VGA_LFB_ADDRESS = 0xE0000000;
/** @const */
var VGA_PIXEL_BUFFER_START = 4 * VGA_BANK_SIZE;
/**
* @const
* Equals the maximum number of pixels for non svga.
* 8 pixels per byte.
*/
var VGA_PIXEL_BUFFER_SIZE = 8 * VGA_BANK_SIZE;
/** @const */
var VGA_MIN_MEMORY_SIZE = VGA_PIXEL_BUFFER_START + VGA_PIXEL_BUFFER_SIZE;
/**
* @const
* @see {@link http://www.osdever.net/FreeVGA/vga/graphreg.htm#06}
*/
var VGA_HOST_MEMORY_SPACE_START = Uint32Array.from([
0xA0000,
0xA0000,
0xB0000,
0xB8000,
]);
/**
* @const
* @see {@link http://www.osdever.net/FreeVGA/vga/graphreg.htm#06}
*/
var VGA_HOST_MEMORY_SPACE_SIZE = Uint32Array.from([
0x20000, // 128K
0x10000, // 64K
0x8000, // 32K
0x8000, // 32K
]);
/**
* @constructor
* @param {CPU} cpu
* @param {BusConnector} bus
* @param {number} vga_memory_size
*/
function VGAScreen(cpu, bus, vga_memory_size)
{
/** @const @type {BusConnector} */
this.bus = bus;
this.vga_memory_size = vga_memory_size;
/** @type {number} */
this.cursor_address = 0;
/** @type {number} */
this.cursor_scanline_start = 0xE;
/** @type {number} */
this.cursor_scanline_end = 0xF;
/**
* Number of columns in text mode
* @type {number}
*/
this.max_cols = 80;
/**
* Number of rows in text mode
* @type {number}
*/
this.max_rows = 25;
/**
* Width in pixels in graphical mode
* @type {number}
*/
this.screen_width = 0;
/**
* Height in pixels in graphical mode
* @type {number}
*/
this.screen_height = 0;
/**
* Logical width in pixels of virtual buffer available for panning
* @type {number}
*/
this.virtual_width = 0;
/**
* Logical height in pixels of virtual buffer available for panning
* @type {number}
*/
this.virtual_height = 0;
/**
* The rectangular fragments of the image buffer, and their destination
* locations, to be drawn every screen_fill_buffer during VGA modes.
* @type {Array<Object<string, number>>}
*/
this.layers = [];
/**
* video memory start address
* @type {number}
*/
this.start_address = 0;
/**
* Start address - a copy of start_address that only gets updated
* during VSync, used for panning and page flipping
* @type {number}
*/
this.start_address_latched = 0;
/**
* Unimplemented CRTC registers go here
*/
this.crtc = new Uint8Array(0x19);
// Implemented CRTC registers:
/** @type {number} */
this.crtc_mode = 0;
/** @type {number} */
this.horizontal_display_enable_end = 0;
/** @type {number} */
this.horizontal_blank_start = 0;
/** @type {number} */
this.vertical_display_enable_end = 0;
/** @type {number} */
this.vertical_blank_start = 0;
/** @type {number} */
this.underline_location_register = 0;
/** @type {number} */
this.preset_row_scan = 0;
/** @type {number} */
this.offset_register = 0;
/** @type {number} */
this.line_compare = 0;
// End of CRTC registers
/**
* Used for svga, e.g. banked modes
* @type{boolean}
*/
this.graphical_mode_is_linear = true;
/** @type {boolean} */
this.graphical_mode = false;
setTimeout(() => { bus.send("screen-set-mode", this.graphical_mode); }, 0);
/*
* VGA palette containing 256 colors for video mode 13, svga 8bpp, etc.
* Needs to be initialised by the BIOS
*/
this.vga256_palette = new Int32Array(256);
/**
* VGA read latches
* @type{number}
*/
this.latch_dword = 0;
/** @type {number} */
this.svga_width = 0;
/** @type {number} */
this.svga_height = 0;
this.svga_enabled = false;
/** @type {number} */
this.svga_bpp = 32;
/** @type {number} */
this.svga_bank_offset = 0;
/**
* The video buffer offset created by VBE_DISPI_INDEX_Y_OFFSET
* In bytes
* @type {number}
*/
this.svga_offset = 0;
// Experimental, could probably need some changes
// 01:00.0 VGA compatible controller: NVIDIA Corporation GT216 [GeForce GT 220] (rev a2)
this.pci_space = [
0xde, 0x10, 0x20, 0x0a, 0x07, 0x00, 0x00, 0x00, 0xa2, 0x00, 0x00, 0x03, 0x00, 0x00, 0x80, 0x00,
0x08, VGA_LFB_ADDRESS >>> 8, VGA_LFB_ADDRESS >>> 16, VGA_LFB_ADDRESS >>> 24,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0a, 0x01, 0x00, 0x00,
];
this.pci_id = 0x12 << 3;
this.pci_bars = [
{
size: vga_memory_size,
},
];
// TODO: Should be matched with vga bios size and mapping address
// Seabios config for this device:
// CONFIG_VGA_PCI=y
// CONFIG_OVERRIDE_PCI_ID=y
// CONFIG_VGA_VID=0x10de
// CONFIG_VGA_DID=0x0a20
this.pci_rom_size = 0x10000;
this.pci_rom_address = 0xFEB00000;
this.name = "vga";
this.stats = {
is_graphical: false,
res_x: 0,
res_y: 0,
bpp: 0,
};
this.index_crtc = 0;
// index for setting colors through port 3C9h
this.dac_color_index_write = 0;
this.dac_color_index_read = 0;
this.dac_state = 0;
this.dac_map = new Uint8Array(0x10);
this.attribute_controller_index = -1;
this.palette_source = 0x20;
this.attribute_mode = 0;
this.color_plane_enable = 0;
this.horizontal_panning = 0;
this.color_select = 0;
this.sequencer_index = -1;
// bitmap of planes 0-3
this.plane_write_bm = 0xF;
this.sequencer_memory_mode = 0;
this.clocking_mode = 0;
this.graphics_index = -1;
this.plane_read = 0, // value 0-3, which plane to read
this.planar_mode = 0;
this.planar_rotate_reg = 0;
this.planar_bitmap = 0xFF;
this.planar_setreset = 0;
this.planar_setreset_enable = 0;
this.miscellaneous_graphics_register = 0;
this.color_compare = 0;
this.color_dont_care = 0;
this.max_scan_line = 0;
this.miscellaneous_output_register = 0xff;
this.port_3DA_value = 0xFF;
var io = cpu.io;
io.register_write(0x3C0, this, this.port3C0_write);
io.register_read(0x3C0, this, this.port3C0_read, this.port3C0_read16);
io.register_read(0x3C1, this, this.port3C1_read);
io.register_write(0x3C2, this, this.port3C2_write);
io.register_write_consecutive(0x3C4, this, this.port3C4_write, this.port3C5_write);
io.register_read(0x3C4, this, this.port3C4_read);
io.register_read(0x3C5, this, this.port3C5_read);
io.register_write_consecutive(0x3CE, this, this.port3CE_write, this.port3CF_write);
io.register_read(0x3CE, this, this.port3CE_read);
io.register_read(0x3CF, this, this.port3CF_read);
io.register_write(0x3C7, this, this.port3C7_write);
io.register_read(0x3C7, this, this.port3C7_read);
io.register_write(0x3C8, this, this.port3C8_write);
io.register_read(0x3C8, this, this.port3C8_read);
io.register_write(0x3C9, this, this.port3C9_write);
io.register_read(0x3C9, this, this.port3C9_read);
io.register_read(0x3CC, this, this.port3CC_read);
io.register_write_consecutive(0x3D4, this, this.port3D4_write, this.port3D5_write);
io.register_read(0x3D4, this, this.port3D4_read);
io.register_read(0x3D5, this, this.port3D5_read);
io.register_read(0x3CA, this, function() { dbg_log("3CA read", LOG_VGA); return 0; });
io.register_read(0x3DA, this, this.port3DA_read);
io.register_read(0x3BA, this, this.port3DA_read);
// Bochs VBE Extensions
// http://wiki.osdev.org/Bochs_VBE_Extensions
this.dispi_index = -1;
this.dispi_enable_value = 0;
io.register_write(0x1CE, this, undefined, this.port1CE_write);
io.register_write(0x1CF, this, undefined, this.port1CF_write);
io.register_read(0x1CF, this, undefined, this.port1CF_read);
if(this.vga_memory_size === undefined || this.vga_memory_size < VGA_MIN_MEMORY_SIZE)
{
this.vga_memory_size = VGA_MIN_MEMORY_SIZE;
dbg_log("vga memory size rounded up to " + this.vga_memory_size, LOG_VGA);
}
else if(this.vga_memory_size & (VGA_BANK_SIZE - 1))
{
// round up to next 64k
this.vga_memory_size |= VGA_BANK_SIZE - 1;
this.vga_memory_size++;
}
this.svga_memory = new Uint8Array(this.vga_memory_size);
this.diff_addr_min = this.vga_memory_size;
this.diff_addr_max = 0;
this.diff_plot_min = this.vga_memory_size;
this.diff_plot_max = 0;
this.dest_buffer = undefined;
bus.register("screen-tell-buffer", function(data)
{
if(this.dest_buffer && data[0])
{
data[0].set(this.dest_buffer.subarray(0, data[0].length));
}
this.dest_buffer = data[0];
}, this);
bus.register("screen-fill-buffer", function()
{
this.screen_fill_buffer();
}, this);
this.svga_memory16 = new Uint16Array(this.svga_memory.buffer);
this.svga_memory32 = new Int32Array(this.svga_memory.buffer);
this.vga_memory = new Uint8Array(this.svga_memory.buffer, 0, 4 * VGA_BANK_SIZE);
this.plane0 = new Uint8Array(this.svga_memory.buffer, 0 * VGA_BANK_SIZE, VGA_BANK_SIZE);
this.plane1 = new Uint8Array(this.svga_memory.buffer, 1 * VGA_BANK_SIZE, VGA_BANK_SIZE);
this.plane2 = new Uint8Array(this.svga_memory.buffer, 2 * VGA_BANK_SIZE, VGA_BANK_SIZE);
this.plane3 = new Uint8Array(this.svga_memory.buffer, 3 * VGA_BANK_SIZE, VGA_BANK_SIZE);
this.pixel_buffer = new Uint8Array(this.svga_memory.buffer,
VGA_PIXEL_BUFFER_START, VGA_PIXEL_BUFFER_SIZE);
var me = this;
io.mmap_register(0xA0000, 0x20000,
function(addr) { return me.vga_memory_read(addr); },
function(addr, value) { me.vga_memory_write(addr, value); }
);
io.mmap_register(VGA_LFB_ADDRESS, this.vga_memory_size,
function(addr) { return me.svga_memory_read8(addr); },
function(addr, value) { me.svga_memory_write8(addr, value); },
function(addr) { return me.svga_memory_read32(addr); },
function(addr, value) { me.svga_memory_write32(addr, value); }
);
cpu.devices.pci.register_device(this);
}
VGAScreen.prototype.get_state = function()
{
var state = [];
state[0] = this.vga_memory_size;
state[1] = this.cursor_address;
state[2] = this.cursor_scanline_start;
state[3] = this.cursor_scanline_end;
state[4] = this.max_cols;
state[5] = this.max_rows;
state[6] = this.layers;
state[7] = this.dac_state;
state[8] = this.start_address;
state[9] = this.graphical_mode;
state[10] = this.vga256_palette;
state[11] = this.latch_dword;
state[12] = this.color_compare;
state[13] = this.color_dont_care;
state[14] = this.miscellaneous_graphics_register;
state[15] = this.svga_width;
state[16] = this.svga_height;
state[17] = this.crtc_mode;
state[18] = this.svga_enabled;
state[19] = this.svga_bpp;
state[20] = this.svga_bank_offset;
state[21] = this.svga_offset;
state[22] = this.index_crtc;
state[23] = this.dac_color_index_write;
state[24] = this.dac_color_index_read;
state[25] = this.dac_map;
state[26] = this.sequencer_index;
state[27] = this.plane_write_bm;
state[28] = this.sequencer_memory_mode;
state[29] = this.graphics_index;
state[30] = this.plane_read;
state[31] = this.planar_mode;
state[32] = this.planar_rotate_reg;
state[33] = this.planar_bitmap;
state[34] = this.max_scan_line;
state[35] = this.miscellaneous_output_register;
state[36] = this.port_3DA_value;
state[37] = this.dispi_index;
state[38] = this.dispi_enable_value;
state[39] = this.svga_memory;
state[40] = this.graphical_mode_is_linear;
state[41] = this.attribute_controller_index;
state[42] = this.offset_register;
state[43] = this.planar_setreset;
state[44] = this.planar_setreset_enable;
state[45] = this.start_address_latched;
state[46] = this.crtc;
state[47] = this.horizontal_display_enable_end;
state[48] = this.horizontal_blank_start;
state[49] = this.vertical_display_enable_end;
state[50] = this.vertical_blank_start;
state[51] = this.underline_location_register;
state[52] = this.preset_row_scan;
state[53] = this.offset_register;
state[54] = this.palette_source;
state[55] = this.attribute_mode;
state[56] = this.color_plane_enable;
state[57] = this.horizontal_panning;
state[58] = this.color_select;
state[59] = this.clocking_mode;
state[60] = this.line_compare;
return state;
};
VGAScreen.prototype.set_state = function(state)
{
this.vga_memory_size = state[0];
this.cursor_address = state[1];
this.cursor_scanline_start = state[2];
this.cursor_scanline_end = state[3];
this.max_cols = state[4];
this.max_rows = state[5];
this.layers = state[6];
this.dac_state = state[7];
this.start_address = state[8];
this.graphical_mode = state[9];
this.vga256_palette = state[10];
this.latch_dword = state[11];
this.color_compare = state[12];
this.color_dont_care = state[13];
this.miscellaneous_graphics_register = state[14];
this.svga_width = state[15];
this.svga_height = state[16];
this.crtc_mode = state[17];
this.svga_enabled = state[18];
this.svga_bpp = state[19];
this.svga_bank_offset = state[20];
this.svga_offset = state[21];
this.index_crtc = state[22];
this.dac_color_index_write = state[23];
this.dac_color_index_read = state[24];
this.dac_map = state[25];
this.sequencer_index = state[26];
this.plane_write_bm = state[27];
this.sequencer_memory_mode = state[28];
this.graphics_index = state[29];
this.plane_read = state[30];
this.planar_mode = state[31];
this.planar_rotate_reg = state[32];
this.planar_bitmap = state[33];
this.max_scan_line = state[34];
this.miscellaneous_output_register = state[35];
this.port_3DA_value = state[36];
this.dispi_index = state[37];
this.dispi_enable_value = state[38];
this.svga_memory.set(state[39]);
this.graphical_mode_is_linear = state[40];
this.attribute_controller_index = state[41];
this.offset_register = state[42];
this.planar_setreset = state[43];
this.planar_setreset_enable = state[44];
this.start_address_latched = state[45];
this.crtc.set(state[46]);
this.horizontal_display_enable_end = state[47];
this.horizontal_blank_start = state[48];
this.vertical_display_enable_end = state[49];
this.vertical_blank_start = state[50];
this.underline_location_register = state[51];
this.preset_row_scan = state[52];
this.offset_register = state[53];
this.palette_source = state[54];
this.attribute_mode = state[55];
this.color_plane_enable = state[56];
this.horizontal_panning = state[57];
this.color_select = state[58];
this.clocking_mode = state[59];
this.line_compare = state[60];
this.bus.send("screen-set-mode", this.graphical_mode);
if(this.graphical_mode)
{
// Ensure set_size_graphical will update
this.screen_width = 0;
this.screen_height = 0;
if(this.svga_enabled)
{
this.set_size_graphical(this.svga_width, this.svga_height,
this.svga_bpp, this.svga_width, this.svga_height);
this.update_layers();
}
else
{
this.update_vga_size();
this.complete_replot();
}
}
else
{
this.set_size_text(this.max_cols, this.max_rows);
this.update_cursor_scanline();
this.update_cursor();
}
this.complete_redraw();
};
VGAScreen.prototype.vga_memory_read = function(addr)
{
if(this.svga_enabled && this.graphical_mode_is_linear)
{
addr -= 0xA0000;
addr |= this.svga_bank_offset;
return this.svga_memory[addr];
}
var memory_space_select = this.miscellaneous_graphics_register >> 2 & 0x3;
addr -= VGA_HOST_MEMORY_SPACE_START[memory_space_select];
// VGA chip only decodes addresses within the selected memory space.
if(addr < 0 || addr >= VGA_HOST_MEMORY_SPACE_SIZE[memory_space_select])
{
dbg_log("vga read outside memory space: addr:" + h(addr), LOG_VGA);
return 0;
}
this.latch_dword = this.plane0[addr];
this.latch_dword |= this.plane1[addr] << 8;
this.latch_dword |= this.plane2[addr] << 16;
this.latch_dword |= this.plane3[addr] << 24;
if(this.planar_mode & 0x08)
{
// read mode 1
var reading = 0xFF;
if(this.color_dont_care & 0x1)
{
reading &= this.plane0[addr] ^ ~(this.color_compare & 0x1 ? 0xFF : 0x00);
}
if(this.color_dont_care & 0x2)
{
reading &= this.plane1[addr] ^ ~(this.color_compare & 0x2 ? 0xFF : 0x00);
}
if(this.color_dont_care & 0x4)
{
reading &= this.plane2[addr] ^ ~(this.color_compare & 0x4 ? 0xFF : 0x00);
}
if(this.color_dont_care & 0x8)
{
reading &= this.plane3[addr] ^ ~(this.color_compare & 0x8 ? 0xFF : 0x00);
}
return reading;
}
else
{
// read mode 0
var plane = this.plane_read;
if(!this.graphical_mode)
{
// We currently put all text data linearly
plane = 0;
}
else if(this.sequencer_memory_mode & 0x8)
{
// Chain 4
plane = addr & 0x3;
addr &= ~0x3;
}
else if(this.planar_mode & 0x10)
{
// Odd/Even host read
plane = addr & 0x1;
addr &= ~0x1;
}
return this.vga_memory[plane << 16 | addr];
}
};
VGAScreen.prototype.vga_memory_write = function(addr, value)
{
if(this.svga_enabled && this.graphical_mode && this.graphical_mode_is_linear)
{
// vbe banked mode
addr -= 0xA0000;
this.vga_memory_write_graphical_linear(addr, value);
return;
}
var memory_space_select = this.miscellaneous_graphics_register >> 2 & 0x3;
addr -= VGA_HOST_MEMORY_SPACE_START[memory_space_select];
if(addr < 0 || addr >= VGA_HOST_MEMORY_SPACE_SIZE[memory_space_select])
{
dbg_log("vga write outside memory space: addr:" + h(addr) + ", value:" + h(value), LOG_VGA);
return;
}
if(this.graphical_mode)
{
this.vga_memory_write_graphical(addr, value);
}
else
{
if(!(this.plane_write_bm & 0x3))
{
// Ignore writes to font planes.
return;
}
this.vga_memory_write_text_mode(addr, value);
}
};
VGAScreen.prototype.vga_memory_write_graphical_linear = function(addr, value)
{
addr |= this.svga_bank_offset;
this.diff_addr_min = addr < this.diff_addr_min ? addr : this.diff_addr_min;
this.diff_addr_max = addr > this.diff_addr_max ? addr : this.diff_addr_max;
this.svga_memory[addr] = value;
};
VGAScreen.prototype.vga_memory_write_graphical = function(addr, value)
{
var plane_dword;
var write_mode = this.planar_mode & 3;
var bitmask = this.apply_feed(this.planar_bitmap);
var setreset_dword = this.apply_expand(this.planar_setreset);
var setreset_enable_dword = this.apply_expand(this.planar_setreset_enable);
// Write modes - see http://www.osdever.net/FreeVGA/vga/graphreg.htm#05
switch(write_mode)
{
case 0:
value = this.apply_rotate(value);
plane_dword = this.apply_feed(value);
plane_dword = this.apply_setreset(plane_dword, setreset_enable_dword);
plane_dword = this.apply_logical(plane_dword, this.latch_dword);
plane_dword = this.apply_bitmask(plane_dword, bitmask);
break;
case 1:
plane_dword = this.latch_dword;
break;
case 2:
plane_dword = this.apply_expand(value);
plane_dword = this.apply_logical(plane_dword, this.latch_dword);
plane_dword = this.apply_bitmask(plane_dword, bitmask);
break;
case 3:
value = this.apply_rotate(value);
bitmask &= this.apply_feed(value);
plane_dword = setreset_dword;
plane_dword = this.apply_bitmask(plane_dword, bitmask);
break;
}
var plane_select = 0xF;
switch(this.sequencer_memory_mode & 0xC)
{
// Odd/Even (aka chain 2)
case 0x0:
plane_select = 0x5 << (addr & 0x1);
addr &= ~0x1;
break;
// Chain 4
// Note: FreeVGA may have mistakenly stated that this bit field is
// for system read only, yet the IBM Open Source Graphics Programmer's
// Reference Manual explicitly states "both read and write".
case 0x8:
case 0xC:
plane_select = 1 << (addr & 0x3);
addr &= ~0x3;
break;
}
// Plane masks take precedence
// See: http://www.osdever.net/FreeVGA/vga/seqreg.htm#02
plane_select &= this.plane_write_bm;
if(plane_select & 0x1) this.plane0[addr] = (plane_dword >> 0) & 0xFF;
if(plane_select & 0x2) this.plane1[addr] = (plane_dword >> 8) & 0xFF;
if(plane_select & 0x4) this.plane2[addr] = (plane_dword >> 16) & 0xFF;
if(plane_select & 0x8) this.plane3[addr] = (plane_dword >> 24) & 0xFF;
var pixel_addr = this.vga_addr_to_pixel(addr);
this.partial_replot(pixel_addr, pixel_addr + 7);
};
/**
* Copies data_byte into the four planes, with each plane
* represented by an 8-bit field inside the dword.
* @param {number} data_byte
* @return {number} 32-bit number representing the bytes for each plane.
*/
VGAScreen.prototype.apply_feed = function(data_byte)
{
var dword = data_byte;
dword |= data_byte << 8;
dword |= data_byte << 16;
dword |= data_byte << 24;
return dword;
};
/**
* Expands bits 0 to 3 to ocupy bits 0 to 31. Each
* bit is expanded to 0xFF if set or 0x00 if clear.
* @param {number} data_byte
* @return {number} 32-bit number representing the bytes for each plane.
*/
VGAScreen.prototype.apply_expand = function(data_byte)
{
var dword = data_byte & 0x1 ? 0xFF : 0x00;
dword |= (data_byte & 0x2 ? 0xFF : 0x00) << 8;
dword |= (data_byte & 0x4 ? 0xFF : 0x00) << 16;
dword |= (data_byte & 0x8 ? 0xFF : 0x00) << 24;
return dword;
};
/**
* Planar Write - Barrel Shifter
* @param {number} data_byte
* @return {number}
* @see {@link http://www.phatcode.net/res/224/files/html/ch25/25-01.html#Heading3}
* @see {@link http://www.osdever.net/FreeVGA/vga/graphreg.htm#03}
*/
VGAScreen.prototype.apply_rotate = function(data_byte)
{
var wrapped = data_byte | (data_byte << 8);
var count = this.planar_rotate_reg & 0x7;
var shifted = wrapped >>> count;
return shifted & 0xFF;
};
/**
* Planar Write - Set / Reset Circuitry
* @param {number} data_dword
* @param {number} enable_dword
* @return {number}
* @see {@link http://www.phatcode.net/res/224/files/html/ch25/25-03.html#Heading5}
* @see {@link http://www.osdever.net/FreeVGA/vga/graphreg.htm#00}
*/
VGAScreen.prototype.apply_setreset = function(data_dword, enable_dword)
{
var setreset_dword = this.apply_expand(this.planar_setreset);
data_dword |= enable_dword & setreset_dword;
data_dword &= ~enable_dword | setreset_dword;
return data_dword;
};
/**
* Planar Write - ALU Unit
* @param {number} data_dword
* @param {number} latch_dword
* @return {number}
* @see {@link http://www.phatcode.net/res/224/files/html/ch24/24-01.html#Heading3}
* @see {@link http://www.osdever.net/FreeVGA/vga/graphreg.htm#03}
*/
VGAScreen.prototype.apply_logical = function(data_dword, latch_dword)
{
switch(this.planar_rotate_reg & 0x18)
{
case 0x08:
return data_dword & latch_dword;
case 0x10:
return data_dword | latch_dword;
case 0x18:
return data_dword ^ latch_dword;
}
return data_dword;
};
/**
* Planar Write - Bitmask Unit
* @param {number} data_dword
* @param {number} bitmask_dword
* @return {number}
* @see {@link http://www.phatcode.net/res/224/files/html/ch25/25-01.html#Heading2}
* @see {@link http://www.osdever.net/FreeVGA/vga/graphreg.htm#08}
*/
VGAScreen.prototype.apply_bitmask = function(data_dword, bitmask_dword)
{
var plane_dword = bitmask_dword & data_dword;
plane_dword |= ~bitmask_dword & this.latch_dword;
return plane_dword;
};
VGAScreen.prototype.text_mode_redraw = function()
{
var addr = this.start_address << 1,
chr,
color;
for(var row = 0; row < this.max_rows; row++)
{
for(var col = 0; col < this.max_cols; col++)
{
chr = this.vga_memory[addr];
color = this.vga_memory[addr | 1];
this.bus.send("screen-put-char", [row, col, chr,
this.vga256_palette[color >> 4 & 0xF], this.vga256_palette[color & 0xF]]);
addr += 2;
}
}
};
VGAScreen.prototype.vga_memory_write_text_mode = function(addr, value)
{
var memory_start = (addr >> 1) - this.start_address,
row = memory_start / this.max_cols | 0,
col = memory_start % this.max_cols,
chr,
color;
// XXX: Should handle 16 bit write if possible
if(addr & 1)
{
color = value;
chr = this.vga_memory[addr & ~1];
}
else
{
chr = value;
color = this.vga_memory[addr | 1];
}
this.bus.send("screen-put-char", [row, col, chr,
this.vga256_palette[color >> 4 & 0xF], this.vga256_palette[color & 0xF]]);
this.vga_memory[addr] = value;
};
VGAScreen.prototype.update_cursor = function()
{
var row = (this.cursor_address - this.start_address) / this.max_cols | 0,
col = (this.cursor_address - this.start_address) % this.max_cols;
row = Math.min(this.max_rows - 1, row);
this.bus.send("screen-update-cursor", [row, col]);
};
VGAScreen.prototype.svga_memory_read8 = function(addr)
{
return this.svga_memory[addr & 0xFFFFFFF];
};
VGAScreen.prototype.svga_memory_read32 = function(addr)
{
addr &= 0xFFFFFFF;
if(addr & 3)
{
return this.svga_memory[addr] | this.svga_memory[addr + 1] << 8 |
this.svga_memory[addr + 2] << 16 | this.svga_memory[addr + 3] << 24;
}
else
{
return this.svga_memory32[addr >> 2];
}
};
VGAScreen.prototype.svga_memory_write8 = function(addr, value)
{
addr &= 0xFFFFFFF;
this.svga_memory[addr] = value;
this.diff_addr_min = addr < this.diff_addr_min ? addr : this.diff_addr_min;
this.diff_addr_max = addr > this.diff_addr_max ? addr : this.diff_addr_max;
};
VGAScreen.prototype.svga_memory_write32 = function(addr, value)
{
addr &= 0xFFFFFFF;
this.diff_addr_min = addr < this.diff_addr_min ? addr : this.diff_addr_min;
this.diff_addr_max = addr + 3 > this.diff_addr_max ? addr + 3 : this.diff_addr_max;
this.svga_memory[addr] = value;
this.svga_memory[addr + 1] = value >> 8;
this.svga_memory[addr + 2] = value >> 16;
this.svga_memory[addr + 3] = value >> 24;
};
VGAScreen.prototype.complete_redraw = function()
{
dbg_log("complete redraw", LOG_VGA);
if(this.graphical_mode)
{
this.diff_addr_min = 0;
if(this.svga_enabled)
{
this.diff_addr_max = this.vga_memory_size;
}
else
{
this.diff_addr_max = VGA_PIXEL_BUFFER_SIZE;
}
}
else
{
this.text_mode_redraw();
}
};
VGAScreen.prototype.complete_replot = function()
{
dbg_log("complete replot", LOG_VGA);
if(!this.graphical_mode || this.svga_enabled)
{
return;
}
this.diff_plot_min = 0;
this.diff_plot_max = VGA_PIXEL_BUFFER_SIZE;
this.complete_redraw();
};
VGAScreen.prototype.partial_redraw = function(min, max)
{
if(min < this.diff_addr_min) this.diff_addr_min = min;
if(max > this.diff_addr_max) this.diff_addr_max = max;
};
VGAScreen.prototype.partial_replot = function(min, max)
{
if(min < this.diff_plot_min) this.diff_plot_min = min;
if(max > this.diff_plot_max) this.diff_plot_max = max;
this.partial_redraw(min, max);
};
VGAScreen.prototype.reset_diffs = function()
{
this.diff_addr_min = this.vga_memory_size;
this.diff_addr_max = 0;
this.diff_plot_min = this.vga_memory_size;
this.diff_plot_max = 0;
};
VGAScreen.prototype.destroy = function()
{
};
VGAScreen.prototype.vga_bytes_per_line = function()
{
var bytes_per_line = this.offset_register << 2;
if(this.underline_location_register & 0x40) bytes_per_line <<= 1;
else if(this.crtc_mode & 0x40) bytes_per_line >>>= 1;
return bytes_per_line;
};
VGAScreen.prototype.vga_addr_shift_count = function()
{
// Count in multiples of 0x40 for convenience
// Left shift 2 for word mode - 2 bytes per dot clock
var shift_count = 0x80;
// Left shift 3 for byte mode - 1 byte per dot clock
shift_count += ~this.underline_location_register & this.crtc_mode & 0x40;
// Left shift 1 for doubleword mode - 4 bytes per dot clock
shift_count -= this.underline_location_register & 0x40;
// But shift one less if PEL width mode - 2 dot clocks per pixel
shift_count -= this.attribute_mode & 0x40;
return shift_count >>> 6;
};
VGAScreen.prototype.vga_addr_to_pixel = function(addr)
{
var shift_count = this.vga_addr_shift_count();
// Undo effects of substituted bits 13 and 14
// Assumptions:
// - max_scan_line register is set to the values shown below
// - Each scan line stays within the offset alignment
// - No panning and no page flipping after drawing
if(~this.crtc_mode & 0x3)
{
var pixel_addr = addr - this.start_address;
// Remove substituted bits
pixel_addr &= this.crtc_mode << 13 | ~0x6000;
// Convert to 1 pixel per address
pixel_addr <<= shift_count;
// Decompose address
var row = pixel_addr / this.virtual_width | 0;
var col = pixel_addr % this.virtual_width;
switch(this.crtc_mode & 0x3)
{
case 0x2:
// Alternating rows using bit 13
// Assumes max scan line = 1
row = row << 1 | (addr >> 13 & 0x1);
break;
case 0x1:
// Alternating rows using bit 14
// Assumes max scan line = 3
row = row << 1 | (addr >> 14 & 0x1);
break;
case 0x0:
// Cycling through rows using bit 13 and 14
// Assumes max scan line = 3
row = row << 2 | (addr >> 13 & 0x3);
break;
}
// Reassemble address
return row * this.virtual_width + col + (this.start_address << shift_count);
}
else
{
// Convert to 1 pixel per address
return addr << shift_count;
}
};
VGAScreen.prototype.scan_line_to_screen_row = function(scan_line)
{
// Double scanning. The clock to the row scan counter is halved
// so it is not affected by the memory address bit substitutions below
if(this.max_scan_line & 0x80)
{
scan_line >>>= 1;
}
// Maximum scan line, aka scan lines per character row
// This is the number of repeats - 1 for graphic modes
var repeat_factor = 1 + (this.max_scan_line & 0x1F);
scan_line = Math.ceil(scan_line / repeat_factor);
// Odd and Even Row Scan Counter
// Despite repeated address counter values, because bit 13 of the shifted
// address is substituted with bit 0 of the row scan counter, a different
// display buffer address is generated instead of repeated
// Assumes maximum scan line register is set to 2 or 4.
// Note: can't assert this as register values may not be fully programmed.
if(!(this.crtc_mode & 0x1))
{
scan_line <<= 1;
}
// Undo effects of substituted bit 14
// Assumes maximum scan line register is set to 2 or 4
// Note: can't assert this as register values may not be fully programmed.
// Other maximum scan line register values would result in weird addressing
// anyway
if(!(this.crtc_mode & 0x2))
{
scan_line <<= 1;
}
return scan_line;
};
/**
* @param {number} cols_count
* @param {number} rows_count
*/
VGAScreen.prototype.set_size_text = function(cols_count, rows_count)
{
this.max_cols = cols_count;
this.max_rows = rows_count;
this.bus.send("screen-set-size-text", [cols_count, rows_count]);
};
VGAScreen.prototype.set_size_graphical = function(width, height, bpp, virtual_width, virtual_height)
{
var needs_update = !this.stats.is_graphical ||
this.stats.bpp !== bpp ||
this.screen_width !== width ||
this.screen_height !== height ||
this.virtual_width !== virtual_width ||
this.virtual_height !== virtual_height;
if(needs_update)
{
this.screen_width = width;
this.screen_height = height;
this.virtual_width = virtual_width;
this.virtual_height = virtual_height;
this.stats.bpp = bpp;
this.stats.is_graphical = true;
this.stats.res_x = width;
this.stats.res_y = height;
this.bus.send("screen-set-size-graphical", [width, height, virtual_width, virtual_height, bpp]);
}
};
VGAScreen.prototype.update_vga_size = function()
{
if(this.svga_enabled)
{
return;
}
var horizontal_characters = Math.min(1 + this.horizontal_display_enable_end,
this.horizontal_blank_start);
var vertical_scans = Math.min(1 + this.vertical_display_enable_end,
this.vertical_blank_start);
if(!horizontal_characters || !vertical_scans)
{
// Don't update if width or height is zero.
// These happen when registers are not fully configured yet.
return;
}
if(this.graphical_mode)
{
var screen_width = horizontal_characters << 3;
// Offset is half the number of bytes/words/dwords (depending on clocking mode)
// of display memory that each logical line occupies.
// However, the number of pixels latched, regardless of addressing mode,
// should always 8 pixels per character clock (except for 8 bit PEL width, in which
// case 4 pixels).
var virtual_width = this.offset_register << 4;
// Pixel Width / PEL Width / Clock Select
if(this.attribute_mode & 0x40)
{
screen_width >>>= 1;
virtual_width >>>= 1;
}
var screen_height = this.scan_line_to_screen_row(vertical_scans);
// The virtual buffer height is however many rows of data that can fit.
// Previously drawn graphics outside of current memory address space can
// still be drawn by setting start_address. The address at
// VGA_HOST_MEMORY_SPACE_START[memory_space_select] is mapped to the first
// byte of the frame buffer. Verified on some hardware.
// Depended on by: Windows 98 start screen
var available_bytes = VGA_HOST_MEMORY_SPACE_SIZE[0];
var virtual_height = Math.ceil(available_bytes / this.vga_bytes_per_line());
this.set_size_graphical(screen_width, screen_height, 8,
virtual_width, virtual_height);
this.update_vertical_retrace();
this.update_layers();
}
else
{
if(this.max_scan_line & 0x80)
{
// Double scanning means that half of those scan lines
// are just repeats
vertical_scans >>>= 1;
}
var height = vertical_scans / (1 + (this.max_scan_line & 0x1F)) | 0;
if(horizontal_characters && height)
{
this.set_size_text(horizontal_characters, height);
}
}
};
VGAScreen.prototype.update_layers = function()
{
if(!this.graphical_mode)
{
this.text_mode_redraw();
}
if(this.svga_enabled)
{
this.layers = [];
return;
}
if(!this.virtual_width || !this.screen_width)
{
// Avoid division by zero
return;
}
if(!this.palette_source || (this.clocking_mode & 0x20))
{
// Palette source and screen disable bits = draw nothing
// See http://www.phatcode.net/res/224/files/html/ch29/29-05.html#Heading6
// and http://www.osdever.net/FreeVGA/vga/seqreg.htm#01
this.layers = [];
this.bus.send("screen-clear");
return;
}
var start_addr = this.start_address_latched;
var pixel_panning = this.horizontal_panning;
if(this.attribute_mode & 0x40)
{
pixel_panning >>>= 1;
}
var byte_panning = this.preset_row_scan >> 5 & 0x3;
var pixel_addr_start = this.vga_addr_to_pixel(start_addr + byte_panning);
var start_buffer_row = pixel_addr_start / this.virtual_width | 0;
var start_buffer_col = pixel_addr_start % this.virtual_width + pixel_panning;
var split_screen_row = this.scan_line_to_screen_row(1 + this.line_compare);
split_screen_row = Math.min(split_screen_row, this.screen_height);
var split_buffer_height = this.screen_height - split_screen_row;
this.layers = [];
for(var x = -start_buffer_col, y = 0; x < this.screen_width; x += this.virtual_width, y++)
{
this.layers.push({
screen_x: x,
screen_y: 0,
buffer_x: 0,
buffer_y: start_buffer_row + y,
buffer_width: this.virtual_width,
buffer_height: split_screen_row,
});
}
var start_split_col = 0;
if(!(this.attribute_mode & 0x20))
{
// Pixel panning mode. Allow panning for the lower split screen
start_split_col = this.vga_addr_to_pixel(byte_panning) + pixel_panning;
}
for(var x = -start_split_col, y = 0; x < this.screen_width; x += this.virtual_width, y++)
{
this.layers.push({
screen_x: x,
screen_y: split_screen_row,
buffer_x: 0,
buffer_y: y,
buffer_width: this.virtual_width,
buffer_height: split_buffer_height,
});
}
};
VGAScreen.prototype.update_vertical_retrace = function()
{
// Emulate behaviour during VSync/VRetrace
this.port_3DA_value |= 0x8;
if(this.start_address_latched !== this.start_address)
{
this.start_address_latched = this.start_address;
this.update_layers();
}
};
VGAScreen.prototype.update_cursor_scanline = function()
{
this.bus.send("screen-update-cursor-scanline", [this.cursor_scanline_start, this.cursor_scanline_end]);
};
/**
* Attribute controller register / index write
* @see {@link http://www.osdever.net/FreeVGA/vga/attrreg.htm}
* @see {@link http://www.mcamafia.de/pdf/ibm_vgaxga_trm2.pdf} page 89
* @see {@link https://01.org/sites/default/files/documentation/intel-gfx-prm-osrc-hsw-display_0.pdf} page 48
*/
VGAScreen.prototype.port3C0_write = function(value)
{
if(this.attribute_controller_index === -1)
{
dbg_log("attribute controller index register: " + h(value), LOG_VGA);
this.attribute_controller_index = value & 0x1F;
dbg_log("attribute actual index: " + h(this.attribute_controller_index), LOG_VGA);
if(this.palette_source !== (value & 0x20))
{
// A method of blanking the screen.
// See http://www.phatcode.net/res/224/files/html/ch29/29-05.html#Heading6
this.palette_source = value & 0x20;
this.update_layers();
}
}
else
{
if(this.attribute_controller_index < 0x10)
{
dbg_log("internal palette: " + h(this.attribute_controller_index) + " -> " + h(value), LOG_VGA);
this.dac_map[this.attribute_controller_index] = value;
if(!(this.attribute_mode & 0x40))
{
this.complete_redraw();
}
}
else
switch(this.attribute_controller_index)
{
case 0x10:
dbg_log("3C0 / attribute mode control: " + h(value), LOG_VGA);
if(this.attribute_mode !== value)
{
var previous_mode = this.attribute_mode;
this.attribute_mode = value;
var is_graphical = (value & 0x1) > 0;
if(!this.svga_enabled && this.graphical_mode !== is_graphical)
{
this.graphical_mode = is_graphical;
this.bus.send("screen-set-mode", this.graphical_mode);
}
if((previous_mode ^ value) & 0x40)
{
// PEL width changed. Pixel Buffer now invalidated
this.complete_replot();
}
this.update_vga_size();
// Data stored in image buffer are invalidated
this.complete_redraw();
}
break;
case 0x12:
dbg_log("3C0 / color plane enable: " + h(value), LOG_VGA);
if(this.color_plane_enable !== value)
{
this.color_plane_enable = value;
// Data stored in image buffer are invalidated
this.complete_redraw();
}
break;
case 0x13:
dbg_log("3C0 / horizontal panning: " + h(value), LOG_VGA);
if(this.horizontal_panning !== value)
{
this.horizontal_panning = value & 0xF;
this.update_layers();
}
break;
case 0x14:
dbg_log("3C0 / color select: " + h(value), LOG_VGA);
if(this.color_select !== value)
{
this.color_select = value;
// Data stored in image buffer are invalidated
this.complete_redraw();
}
break;
default:
dbg_log("3C0 / attribute controller write " + h(this.attribute_controller_index) + ": " + h(value), LOG_VGA);
}
this.attribute_controller_index = -1;
}
};
VGAScreen.prototype.port3C0_read = function()
{
dbg_log("3C0 read", LOG_VGA);
var result = this.attribute_controller_index | this.palette_source;
return result;
};
VGAScreen.prototype.port3C0_read16 = function()
{
dbg_log("3C0 read16", LOG_VGA);
return this.port3C0_read() & 0xFF | this.port3C1_read() << 8 & 0xFF00;
};
VGAScreen.prototype.port3C1_read = function()
{
if(this.attribute_controller_index < 0x10)
{
dbg_log("3C1 / internal palette read: " + h(this.attribute_controller_index) +
" -> " + h(this.dac_map[this.attribute_controller_index]), LOG_VGA);
return this.dac_map[this.attribute_controller_index];
}
switch(this.attribute_controller_index)
{
case 0x10:
dbg_log("3C1 / attribute mode read: " + h(this.attribute_mode), LOG_VGA);
return this.attribute_mode;
case 0x12:
dbg_log("3C1 / color plane enable read: " + h(this.color_plane_enable), LOG_VGA);
return this.color_plane_enable;
case 0x13:
dbg_log("3C1 / horizontal panning read: " + h(this.horizontal_panning), LOG_VGA);
return this.horizontal_panning;
case 0x14:
dbg_log("3C1 / color select read: " + h(this.color_select), LOG_VGA);
return this.color_select;
default:
dbg_log("3C1 / attribute controller read " + h(this.attribute_controller_index), LOG_VGA);
}
return -1;
};
VGAScreen.prototype.port3C2_write = function(value)
{
dbg_log("3C2 / miscellaneous output register = " + h(value), LOG_VGA);
this.miscellaneous_output_register = value;
};
VGAScreen.prototype.port3C4_write = function(value)
{
this.sequencer_index = value;
};
VGAScreen.prototype.port3C4_read = function()
{
return this.sequencer_index;
};
/**
* Sequencer register writes
* @see {@link http://www.osdever.net/FreeVGA/vga/seqreg.htm}
* @see {@link http://www.mcamafia.de/pdf/ibm_vgaxga_trm2.pdf} page 47
* @see {@link https://01.org/sites/default/files/documentation/intel-gfx-prm-osrc-hsw-display_0.pdf} page 19
*/
VGAScreen.prototype.port3C5_write = function(value)
{
switch(this.sequencer_index)
{
case 0x01:
dbg_log("clocking mode: " + h(value), LOG_VGA);
var previous_clocking_mode = this.clocking_mode;
this.clocking_mode = value;
if((previous_clocking_mode ^ value) & 0x20)
{
// Screen disable bit modified
this.update_layers();
}
break;
case 0x02:
dbg_log("plane write mask: " + h(value), LOG_VGA);
this.plane_write_bm = value;
break;
case 0x04:
dbg_log("sequencer memory mode: " + h(value), LOG_VGA);
this.sequencer_memory_mode = value;
break;
default:
dbg_log("3C5 / sequencer write " + h(this.sequencer_index) + ": " + h(value), LOG_VGA);
}
};
VGAScreen.prototype.port3C5_read = function()
{
dbg_log("3C5 / sequencer read " + h(this.sequencer_index), LOG_VGA);
switch(this.sequencer_index)
{
case 0x01:
return this.clocking_mode;
case 0x02:
return this.plane_write_bm;
case 0x04:
return this.sequencer_memory_mode;
case 0x06:
return 0x12;
default:
}
return 0;
};
VGAScreen.prototype.port3C7_write = function(index)
{
// index for reading the DAC
dbg_log("3C7 write: " + h(index), LOG_VGA);
this.dac_color_index_read = index * 3;
this.dac_state &= 0x0;
};
VGAScreen.prototype.port3C7_read = function()
{
// prepared to accept reads or writes
return this.dac_state;
};
VGAScreen.prototype.port3C8_write = function(index)
{
this.dac_color_index_write = index * 3;
this.dac_state |= 0x3;
};
VGAScreen.prototype.port3C8_read = function()
{
return this.dac_color_index_write / 3 | 0;
};
/**
* DAC color palette register writes
* @see {@link http://www.osdever.net/FreeVGA/vga/colorreg.htm}
* @see {@link http://www.mcamafia.de/pdf/ibm_vgaxga_trm2.pdf} page 104
* @see {@link https://01.org/sites/default/files/documentation/intel-gfx-prm-osrc-hsw-display_0.pdf} page 57
*/
VGAScreen.prototype.port3C9_write = function(color_byte)
{
var index = this.dac_color_index_write / 3 | 0,
offset = this.dac_color_index_write % 3,
color = this.vga256_palette[index];
color_byte = (color_byte & 0x3F) * 255 / 63 | 0;
if(offset === 0)
{
color = color & ~0xFF0000 | color_byte << 16;
}
else if(offset === 1)
{
color = color & ~0xFF00 | color_byte << 8;
}
else
{
color = color & ~0xFF | color_byte;
dbg_log("dac set color, index=" + h(index) + " value=" + h(color), LOG_VGA);
}
if(this.vga256_palette[index] !== color)
{
this.vga256_palette[index] = color;
this.complete_redraw();
}
this.dac_color_index_write++;
};
VGAScreen.prototype.port3C9_read = function()
{
dbg_log("3C9 read", LOG_VGA);
var index = this.dac_color_index_read / 3 | 0;
var offset = this.dac_color_index_read % 3;
var color = this.vga256_palette[index];
this.dac_color_index_read++;
return (color >> (2 - offset) * 8 & 0xFF) / 255 * 63 | 0;
};
VGAScreen.prototype.port3CC_read = function()
{
dbg_log("3CC read", LOG_VGA);
return this.miscellaneous_output_register;
};
VGAScreen.prototype.port3CE_write = function(value)
{
this.graphics_index = value;
};
VGAScreen.prototype.port3CE_read = function()
{
return this.graphics_index;
};
/**
* Graphics controller register writes
* @see {@link http://www.osdever.net/FreeVGA/vga/graphreg.htm}
* @see {@link http://www.mcamafia.de/pdf/ibm_vgaxga_trm2.pdf} page 78
* @see {@link https://01.org/sites/default/files/documentation/intel-gfx-prm-osrc-hsw-display_0.pdf} page 29
*/
VGAScreen.prototype.port3CF_write = function(value)
{
switch(this.graphics_index)
{
case 0:
this.planar_setreset = value;
dbg_log("plane set/reset: " + h(value), LOG_VGA);
break;
case 1:
this.planar_setreset_enable = value;
dbg_log("plane set/reset enable: " + h(value), LOG_VGA);
break;
case 2:
this.color_compare = value;
dbg_log("color compare: " + h(value), LOG_VGA);
break;
case 3:
this.planar_rotate_reg = value;
dbg_log("plane rotate: " + h(value), LOG_VGA);
break;
case 4:
this.plane_read = value;
dbg_log("plane read: " + h(value), LOG_VGA);
break;
case 5:
var previous_planar_mode = this.planar_mode;
this.planar_mode = value;
dbg_log("planar mode: " + h(value), LOG_VGA);
if((previous_planar_mode ^ value) & 0x60)
{
// Shift mode modified. Pixel buffer invalidated
this.complete_replot();
}
break;
case 6:
dbg_log("miscellaneous graphics register: " + h(value), LOG_VGA);
if(this.miscellaneous_graphics_register !== value)
{
this.miscellaneous_graphics_register = value;
this.update_vga_size();
}
break;
case 7:
this.color_dont_care = value;
dbg_log("color don't care: " + h(value), LOG_VGA);
break;
case 8:
this.planar_bitmap = value;
dbg_log("planar bitmap: " + h(value), LOG_VGA);
break;
default:
dbg_log("3CF / graphics write " + h(this.graphics_index) + ": " + h(value), LOG_VGA);
}
};
VGAScreen.prototype.port3CF_read = function()
{
dbg_log("3CF / graphics read " + h(this.graphics_index), LOG_VGA);
switch(this.graphics_index)
{
case 0:
return this.planar_setreset;
case 1:
return this.planar_setreset_enable;
case 2:
return this.color_compare;
case 3:
return this.planar_rotate_reg;
case 4:
return this.plane_read;
case 5:
return this.planar_mode;
case 6:
return this.miscellaneous_graphics_register;
case 7:
return this.color_dont_care;
case 8:
return this.planar_bitmap;
default:
}
return 0;
};
VGAScreen.prototype.port3D4_write = function(register)
{
dbg_log("3D4 / crtc index: " + register, LOG_VGA);
this.index_crtc = register;
};
VGAScreen.prototype.port3D4_read = function()
{
dbg_log("3D4 read / crtc index: " + this.index_crtc, LOG_VGA);
return this.index_crtc;
};
/**
* CRT controller register writes
* @see {@link http://www.osdever.net/FreeVGA/vga/crtcreg.htm}
* @see {@link http://www.mcamafia.de/pdf/ibm_vgaxga_trm2.pdf} page 55
* @see {@link https://01.org/sites/default/files/documentation/intel-gfx-prm-osrc-hsw-display_0.pdf} page 63
*/
VGAScreen.prototype.port3D5_write = function(value)
{
switch(this.index_crtc)
{
case 0x1:
dbg_log("3D5 / hdisp enable end write: " + h(value), LOG_VGA);
if(this.horizontal_display_enable_end !== value)
{
this.horizontal_display_enable_end = value;
this.update_vga_size();
}
break;
case 0x2:
if(this.horizontal_blank_start !== value)
{
this.horizontal_blank_start = value;
this.update_vga_size();
}
break;
case 0x7:
dbg_log("3D5 / overflow register write: " + h(value), LOG_VGA);
var previous_vertical_display_enable_end = this.vertical_display_enable_end;
this.vertical_display_enable_end &= 0xFF;
this.vertical_display_enable_end |= (value << 3 & 0x200) | (value << 7 & 0x100);
if(previous_vertical_display_enable_end != this.vertical_display_enable_end)
{
this.update_vga_size();
}
this.line_compare = (this.line_compare & 0x2FF) | (value << 4 & 0x100);
var previous_vertical_blank_start = this.vertical_blank_start;
this.vertical_blank_start = (this.vertical_blank_start & 0x2FF) | (value << 5 & 0x100);
if(previous_vertical_blank_start !== this.vertical_blank_start)
{
this.update_vga_size();
}
this.update_layers();
break;
case 0x8:
dbg_log("3D5 / preset row scan write: " + h(value), LOG_VGA);
this.preset_row_scan = value;
this.update_layers();
break;
case 0x9:
dbg_log("3D5 / max scan line write: " + h(value), LOG_VGA);
this.max_scan_line = value;
this.line_compare = (this.line_compare & 0x1FF) | (value << 3 & 0x200);
var previous_vertical_blank_start = this.vertical_blank_start;
this.vertical_blank_start = (this.vertical_blank_start & 0x1FF) | (value << 4 & 0x200);
if(previous_vertical_blank_start !== this.vertical_blank_start)
{
this.update_vga_size();
}
this.update_layers();
break;
case 0xA:
dbg_log("3D5 / cursor scanline start write: " + h(value), LOG_VGA);
this.cursor_scanline_start = value;
this.update_cursor_scanline();
break;
case 0xB:
dbg_log("3D5 / cursor scanline end write: " + h(value), LOG_VGA);
this.cursor_scanline_end = value;
this.update_cursor_scanline();
break;
case 0xC:
if((this.start_address >> 8 & 0xFF) !== value)
{
this.start_address = this.start_address & 0xff | value << 8;
this.update_layers();
if(~this.crtc_mode & 0x3)
{
// Address substitution implementation depends on the
// starting row and column, so the pixel buffer is invalidated.
this.complete_replot();
}
}
dbg_log("3D5 / start addr hi write: " + h(value) + " -> " + h(this.start_address, 4), LOG_VGA);
break;
case 0xD:
if((this.start_address & 0xFF) !== value)
{
this.start_address = this.start_address & 0xff00 | value;
this.update_layers();
if(~this.crtc_mode & 0x3)
{
// Address substitution implementation depends on the
// starting row and column, so the pixel buffer is invalidated.
this.complete_replot();
}
}
dbg_log("3D5 / start addr lo write: " + h(value) + " -> " + h(this.start_address, 4), LOG_VGA);
break;
case 0xE:
dbg_log("3D5 / cursor address hi write: " + h(value), LOG_VGA);
this.cursor_address = this.cursor_address & 0xFF | value << 8;
this.update_cursor();
break;
case 0xF:
dbg_log("3D5 / cursor address lo write: " + h(value), LOG_VGA);
this.cursor_address = this.cursor_address & 0xFF00 | value;
this.update_cursor();
break;
case 0x12:
dbg_log("3D5 / vdisp enable end write: " + h(value), LOG_VGA);
if((this.vertical_display_enable_end & 0xFF) !== value)
{
this.vertical_display_enable_end = (this.vertical_display_enable_end & 0x300) | value;
this.update_vga_size();
}
break;
case 0x13:
dbg_log("3D5 / offset register write: " + h(value), LOG_VGA);
if(this.offset_register !== value)
{
this.offset_register = value;
this.update_vga_size();
if(~this.crtc_mode & 0x3)
{
// Address substitution implementation depends on the
// virtual width, so the pixel buffer is invalidated.
this.complete_replot();
}
}
break;
case 0x14:
dbg_log("3D5 / underline location write: " + h(value), LOG_VGA);
if(this.underline_location_register !== value)
{
var previous_underline = this.underline_location_register;
this.underline_location_register = value;
this.update_vga_size();
if((previous_underline ^ value) & 0x40)
{
// Doubleword addressing changed. Pixel buffer invalidated.
this.complete_replot();
}
}
break;
case 0x15:
dbg_log("3D5 / vertical blank start write: " + h(value), LOG_VGA);
if((this.vertical_blank_start & 0xFF) !== value)
{
this.vertical_blank_start = (this.vertical_blank_start & 0x300) | value;
this.update_vga_size();
}
break;
case 0x17:
dbg_log("3D5 / crtc mode write: " + h(value), LOG_VGA);
if(this.crtc_mode !== value)
{
var previous_mode = this.crtc_mode;
this.crtc_mode = value;
this.update_vga_size();
if((previous_mode ^ value) & 0x43)
{
// Word/byte addressing changed or address substitution changed.
// Pixel buffer invalidated.
this.complete_replot();
}
}
break;
case 0x18:
dbg_log("3D5 / line compare write: " + h(value), LOG_VGA);
this.line_compare = (this.line_compare & 0x300) | value;
this.update_layers();
break;
default:
if(this.index_crtc < this.crtc.length)
{
this.crtc[this.index_crtc] = value;
}
dbg_log("3D5 / CRTC write " + h(this.index_crtc) + ": " + h(value), LOG_VGA);
}
};
VGAScreen.prototype.port3D5_read = function()
{
dbg_log("3D5 read " + h(this.index_crtc), LOG_VGA);
switch(this.index_crtc)
{
case 0x1:
return this.horizontal_display_enable_end;
case 0x2:
return this.horizontal_blank_start;
case 0x7:
return (this.vertical_display_enable_end >> 7 & 0x2) |
(this.vertical_blank_start >> 5 & 0x8) |
(this.line_compare >> 4 & 0x10) |
(this.vertical_display_enable_end >> 3 & 0x40);
case 0x8:
return this.preset_row_scan;
case 0x9:
return this.max_scan_line;
case 0xA:
return this.cursor_scanline_start;
case 0xB:
return this.cursor_scanline_end;
case 0xC:
return this.start_address & 0xFF;
case 0xD:
return this.start_address >> 8;
case 0xE:
return this.cursor_address >> 8;
case 0xF:
return this.cursor_address & 0xFF;
case 0x12:
return this.vertical_display_enable_end & 0xFF;
case 0x13:
return this.offset_register;
case 0x14:
return this.underline_location_register;
case 0x15:
return this.vertical_blank_start & 0xFF;
case 0x17:
return this.crtc_mode;
case 0x18:
return this.line_compare & 0xFF;
}
if(this.index_crtc < this.crtc.length)
{
return this.crtc[this.index_crtc];
}
else
{
return 0;
}
};
VGAScreen.prototype.port3DA_read = function()
{
dbg_log("3DA read - status 1 and clear attr index", LOG_VGA);
var value = this.port_3DA_value;
// Status register, bit 3 set by update_vertical_retrace
// during screen-fill-buffer
if(!this.graphical_mode)
{
// But screen-fill-buffer may not get triggered in text mode
// so toggle it manually here
if(this.port_3DA_value & 1)
{
this.port_3DA_value ^= 8;
}
this.port_3DA_value ^= 1;
}
else
{
this.port_3DA_value ^= 1;
this.port_3DA_value &= 1;
}
this.attribute_controller_index = -1;
return value;
};
VGAScreen.prototype.svga_bytes_per_line = function()
{
var bits = this.svga_bpp === 15 ? 16 : this.svga_bpp;
return this.svga_width * bits / 8;
};
VGAScreen.prototype.port1CE_write = function(value)
{
this.dispi_index = value;
};
VGAScreen.prototype.port1CF_write = function(value)
{
dbg_log("1CF / dispi write " + h(this.dispi_index) + ": " + h(value), LOG_VGA);
switch(this.dispi_index)
{
case 1:
this.svga_width = value;
if(this.svga_width > MAX_XRES)
{
dbg_log("svga_width reduced from " + this.svga_width + " to " + MAX_XRES, LOG_VGA);
this.svga_width = MAX_XRES;
}
break;
case 2:
this.svga_height = value;
if(this.svga_height > MAX_YRES)
{
dbg_log("svga_height reduced from " + this.svga_height + " to " + MAX_YRES, LOG_VGA);
this.svga_height = MAX_YRES;
}
break;
case 3:
this.svga_bpp = value;
break;
case 4:
// enable, options
this.svga_enabled = (value & 1) === 1;
this.dispi_enable_value = value;
break;
case 5:
this.svga_bank_offset = value << 16;
break;
case 9:
// y offset
this.svga_offset = value * this.svga_bytes_per_line();
dbg_log("SVGA offset: " + h(this.svga_offset) + " y=" + h(value), LOG_VGA);
this.complete_redraw();
break;
default:
}
if(this.svga_enabled && (!this.svga_width || !this.svga_height))
{
dbg_log("SVGA: disabled because of invalid width/height: " + this.svga_width + "x" + this.svga_height, LOG_VGA);
this.svga_enabled = false;
}
dbg_assert(this.svga_bpp !== 4, "unimplemented svga bpp: 4");
dbg_assert(this.svga_bpp !== 15, "unimplemented svga bpp: 15");
dbg_assert(this.svga_bpp === 4 || this.svga_bpp === 8 ||
this.svga_bpp === 15 || this.svga_bpp === 16 ||
this.svga_bpp === 24 || this.svga_bpp === 32,
"unexpected svga bpp: " + this.svga_bpp);
dbg_log("SVGA: enabled=" + this.svga_enabled + ", " + this.svga_width + "x" + this.svga_height + "x" + this.svga_bpp, LOG_VGA);
if(this.svga_enabled && this.dispi_index === 4)
{
this.set_size_graphical(this.svga_width, this.svga_height, this.svga_bpp, this.svga_width, this.svga_height);
this.bus.send("screen-set-mode", true);
this.graphical_mode = true;
this.graphical_mode_is_linear = true;
}
if(!this.svga_enabled)
{
this.svga_bank_offset = 0;
}
this.update_layers();
};
VGAScreen.prototype.port1CF_read = function()
{
dbg_log("1CF / dispi read " + h(this.dispi_index), LOG_VGA);
return this.svga_register_read(this.dispi_index);
};
VGAScreen.prototype.svga_register_read = function(n)
{
switch(n)
{
case 0:
// id
return 0xB0C0;
case 1:
return this.dispi_enable_value & 2 ? MAX_XRES : this.svga_width;
case 2:
return this.dispi_enable_value & 2 ? MAX_YRES : this.svga_height;
case 3:
return this.dispi_enable_value & 2 ? MAX_BPP : this.svga_bpp;
case 4:
return this.dispi_enable_value;
case 5:
return this.svga_bank_offset >>> 16;
case 6:
// virtual width
if(this.screen_width)
{
return this.screen_width;
}
else
{
return 1; // seabios/windows98 divide exception
}
break;
case 8:
// x offset
return 0;
case 0x0A:
// memory size in 64 kilobyte banks
return this.vga_memory_size / VGA_BANK_SIZE | 0;
}
return 0xFF;
};
/**
* Transfers graphics from VGA Planes to the Pixel Buffer
* VGA Planes represent data stored on actual hardware.
* Pixel Buffer caches the 4-bit or 8-bit color indices for each pixel.
*/
VGAScreen.prototype.vga_replot = function()
{
// Round to multiple of 8 towards extreme
var start = this.diff_plot_min & ~0xF;
var end = Math.min((this.diff_plot_max | 0xF), VGA_PIXEL_BUFFER_SIZE - 1);
var addr_shift = this.vga_addr_shift_count();
var addr_substitution = ~this.crtc_mode & 0x3;
var shift_mode = this.planar_mode & 0x60
var pel_width = this.attribute_mode & 0x40;
for(var pixel_addr = start; pixel_addr <= end;)
{
var addr = pixel_addr >>> addr_shift;
if(addr_substitution)
{
var row = pixel_addr / this.virtual_width | 0;
var col = pixel_addr - this.virtual_width * row;
switch(addr_substitution)
{
case 0x1:
// Alternating rows using bit 13
// Assumes max scan line = 1
addr = (row & 0x1) << 13;
row >>>= 1;
break;
case 0x2:
// Alternating rows using bit 14
// Assumes max scan line = 3
addr = (row & 0x1) << 14;
row >>>= 1;
break;
case 0x3:
// Cycling through rows using bit 13 and 14
// Assumes max scan line = 3
addr = (row & 0x3) << 13;
row >>>= 2;
break;
}
addr |= (row * this.virtual_width + col >>> addr_shift) + this.start_address;
}
var byte0 = this.plane0[addr];
var byte1 = this.plane1[addr];
var byte2 = this.plane2[addr];
var byte3 = this.plane3[addr];
var shift_loads = new Uint8Array(8);
switch(shift_mode)
{
// Planar Shift Mode
// See http://www.osdever.net/FreeVGA/vga/vgaseq.htm
case 0x00:
// Shift these, so that the bits for the color are in
// the correct position in the for loop
byte0 <<= 0;
byte1 <<= 1;
byte2 <<= 2;
byte3 <<= 3;
for(var i = 7; i >= 0; i--)
{
shift_loads[7 - i] =
byte0 >> i & 1 |
byte1 >> i & 2 |
byte2 >> i & 4 |
byte3 >> i & 8;
}
break;
// Packed Shift Mode, aka Interleaved Shift Mode
// Video Modes 4h and 5h
case 0x20:
shift_loads[0] = (byte0 >> 6 & 0x3) | (byte2 >> 4 & 0xC);
shift_loads[1] = (byte0 >> 4 & 0x3) | (byte2 >> 2 & 0xC);
shift_loads[2] = (byte0 >> 2 & 0x3) | (byte2 >> 0 & 0xC);
shift_loads[3] = (byte0 >> 0 & 0x3) | (byte2 << 2 & 0xC);
shift_loads[4] = (byte1 >> 6 & 0x3) | (byte3 >> 4 & 0xC);
shift_loads[5] = (byte1 >> 4 & 0x3) | (byte3 >> 2 & 0xC);
shift_loads[6] = (byte1 >> 2 & 0x3) | (byte3 >> 0 & 0xC);
shift_loads[7] = (byte1 >> 0 & 0x3) | (byte3 << 2 & 0xC);
break;
// 256-Color Shift Mode
// Video Modes 13h and unchained 256 color
case 0x40:
case 0x60:
shift_loads[0] = byte0 >> 4 & 0xF;
shift_loads[1] = byte0 >> 0 & 0xF;
shift_loads[2] = byte1 >> 4 & 0xF;
shift_loads[3] = byte1 >> 0 & 0xF;
shift_loads[4] = byte2 >> 4 & 0xF;
shift_loads[5] = byte2 >> 0 & 0xF;
shift_loads[6] = byte3 >> 4 & 0xF;
shift_loads[7] = byte3 >> 0 & 0xF;
break;
}
if(pel_width)
{
// Assemble from two sets of 4 bits.
for(var i = 0, j = 0; i < 4; i++, pixel_addr++, j += 2)
{
this.pixel_buffer[pixel_addr] = (shift_loads[j] << 4) | shift_loads[j + 1];
}
}
else
{
for(var i = 0; i < 8; i++, pixel_addr++)
{
this.pixel_buffer[pixel_addr] = shift_loads[i];
}
}
}
};
/**
* Transfers graphics from Pixel Buffer to Destination Image Buffer.
* The 4-bit/8-bit color indices in the Pixel Buffer are passed through
* the internal palette (dac_map) and the DAC palette (vga256_palette) to
* obtain the final 32 bit color that the Canvas API uses.
*/
VGAScreen.prototype.vga_redraw = function()
{
var start = this.diff_addr_min;
var end = Math.min(this.diff_addr_max, VGA_PIXEL_BUFFER_SIZE - 1);
var buffer = this.dest_buffer;
// Closure compiler
if(!buffer) return;
var mask = 0xFF;
var colorset = 0x00;
if(this.attribute_mode & 0x80)
{
// Palette bits 5/4 select
mask &= 0xCF;
colorset |= this.color_select << 4 & 0x30;
}
if(this.attribute_mode & 0x40)
{
// 8 bit mode
for(var pixel_addr = start; pixel_addr <= end; pixel_addr++)
{
var color256 = (this.pixel_buffer[pixel_addr] & mask) | colorset;
var color = this.vga256_palette[color256];
buffer[pixel_addr] = color & 0xFF00 | color << 16 | color >> 16 | 0xFF000000;
}
}
else
{
// 4 bit mode
// Palette bits 7/6 select
mask &= 0x3F;
colorset |= this.color_select << 4 & 0xC0;
for(var pixel_addr = start; pixel_addr <= end; pixel_addr++)
{
var color16 = this.pixel_buffer[pixel_addr] & this.color_plane_enable;
var color256 = (this.dac_map[color16] & mask) | colorset;
var color = this.vga256_palette[color256];
buffer[pixel_addr] = color & 0xFF00 | color << 16 | color >> 16 | 0xFF000000;
}
}
};
VGAScreen.prototype.screen_fill_buffer = function()
{
if(!this.graphical_mode)
{
// text mode
// Update retrace behaviour anyway - programs waiting for signal before
// changing to graphical mode
this.update_vertical_retrace();
return;
}
if(!this.dest_buffer)
{
dbg_log("Cannot fill buffer: No destination buffer", LOG_VGA);
// Update retrace behaviour anyway
this.update_vertical_retrace();
return;
}
if(this.diff_addr_max < this.diff_addr_min && this.diff_plot_max < this.diff_plot_min)
{
// No pixels to update
this.bus.send("screen-fill-buffer-end", this.layers);
this.update_vertical_retrace();
return;
}
if(this.svga_enabled)
{
var bpp = this.svga_bpp;
var buffer = this.dest_buffer;
var start = this.diff_addr_min;
var end = this.diff_addr_max;
switch(bpp)
{
case 32:
var start_pixel = start >> 2;
var end_pixel = (end >> 2) + 1;
for(var i = start_pixel; i < end_pixel; i++)
{
var dword = this.svga_memory32[i];
buffer[i] = dword << 16 | dword >> 16 & 0xFF | dword & 0xFF00 | 0xFF000000;
}
break;
case 24:
var start_pixel = start / 3 | 0;
var end_pixel = (end / 3 | 0) + 1;
var addr = start_pixel * 3;
for(var i = start_pixel; addr < end; i++)
{
var red = this.svga_memory[addr++];
var green = this.svga_memory[addr++];
var blue = this.svga_memory[addr++];
buffer[i] = red << 16 | green << 8 | blue | 0xFF000000;
}
break;
case 16:
var start_pixel = start >> 1;
var end_pixel = (end >> 1) + 1;
for(var i = start_pixel; i < end_pixel; i++)
{
var word = this.svga_memory16[i];
var blue = (word >> 11) * 0xFF / 0x1F | 0;
var green = (word >> 5 & 0x3F) * 0xFF / 0x3F | 0;
var red = (word & 0x1F) * 0xFF / 0x1F | 0;
buffer[i] = red << 16 | green << 8 | blue | 0xFF000000;
}
break;
case 8:
var start_pixel = start;
var end_pixel = end + 1;
for(var i = start; i <= end; i++)
{
var color = this.vga256_palette[this.svga_memory[i]];
buffer[i] = color & 0xFF00 | color << 16 | color >> 16 | 0xFF000000;
}
break;
default:
dbg_assert(false, "Unsupported BPP: " + bpp);
}
var min_y = start_pixel / this.svga_width | 0;
var max_y = end_pixel / this.svga_width | 0;
this.bus.send("screen-fill-buffer-end", [{
screen_x: 0, screen_y: min_y,
buffer_x: 0, buffer_y: min_y,
buffer_width: this.svga_width,
buffer_height: max_y - min_y + 1,
}]);
}
else
{
this.vga_replot();
this.vga_redraw();
this.bus.send("screen-fill-buffer-end", this.layers);
}
this.reset_diffs();
this.update_vertical_retrace();
};