// ZX-Evo Base Configuration (c) NedoPC 2008,2009,2010,2011,2012,2013,2014
//
// top module for video output.
/*
This file is part of ZX-Evo Base Configuration firmware.
ZX-Evo Base Configuration firmware is free software:
you can redistribute it and/or modify it under the terms of
the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
ZX-Evo Base Configuration firmware is distributed in the hope that
it will be useful, but WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with ZX-Evo Base Configuration firmware.
If not, see <http://www.gnu.org/licenses/>.
*/
// note: the only bandwidths currently in use are 1/8 and 1/4.
`include "../include/tune.v"
module video_top(
input wire clk, // 28 MHz clock
// external video outputs
output wire [ 1:0] vred,
output wire [ 1:0] vgrn,
output wire [ 1:0] vblu,
output wire vhsync,
output wire vvsync,
output wire vcsync,
// aux video inputs
input wire [ 3:0] zxborder, // border zxcolor
// config inputs
input wire [ 1:0] pent_vmode, // 2'b00 - standard ZX
// 2'b01 - hardware multicolor
// 2'b10 - pentagon 16 colors
// 2'b11 - not defined yet
input wire [ 2:0] atm_vmode, // 3'b011 - zx modes (pent_vmode is active)
// 3'b010 - 640x200 hardware multicolor
// 3'b000 - 320x200 16 colors
// 3'b110 - 80x25 text mode
// 3'b??? (others) - not defined yet
input wire scr_page, // screen page (bit 3 of 7FFD)
input wire vga_on, // vga mode ON - scandoubler activated
input wire [ 1:0] modes_raster, // 2'b00 - pentagon raster (71680 clocks)
// 2'b01 - 60Hz raster
// 2'b10 - 48k raster (69888 clocks)
// 2'b11 - 128k raster (70908 clocks)
input wire mode_contend_type, // 2'b0 - 48k/128k/+2 contend type (6 5 4 3 2 1 0 0)
// 2'b1 - +2a/+3 contend type (1 0 7 6 5 4 3 2)
// memory synchronization inputs
input wire cbeg,
input wire post_cbeg,
input wire pre_cend,
input wire cend,
// memory arbiter video port connection
input wire video_strobe,
input wire video_next,
output wire [20:0] video_addr,
input wire [15:0] video_data,
output wire [ 1:0] video_bw,
output wire video_go,
// atm palette write strobe adn data
input wire atm_palwr,
input wire [ 5:0] atm_paldata,
input wire [ 5:0] atm_paldatalow,
input wire pal444_ena,
input wire up_ena,
input wire up_palwr,
input wire [ 5:0] up_paladdr,
input wire [ 7:0] up_paldata,
output wire int_start,
input wire [10:0] fnt_a,
input wire [ 7:0] fnt_d,
input wire fnt_wr,
output wire [ 5:0] palcolor, // for palette readback
output wire [ 7:0] fontrom_readback,
output wire contend // for 48k/128k contended memory emulation
);
// these decoded in video_modedecode.v
wire mode_atm_n_pent;
wire mode_zx;
wire mode_p_16c;
wire mode_p_hmclr;
wire mode_a_hmclr;
wire mode_a_16c;
wire mode_a_text;
wire mode_a_txt_1page;
wire mode_pixf_14;
// synchronization
wire hsync_start;
wire line_start;
wire hint_start;
wire vblank;
wire hblank;
wire vpix;
wire hpix;
wire vsync;
wire hsync;
wire vga_hsync;
wire scanin_start;
wire scanout_start;
wire fetch_start;
wire fetch_end;
wire fetch_sync;
wire [63:0] pic_bits;
wire [3:0] pixels;
wire [5:0] color;
wire [5:0] vga_color;
wire [2:0] typos;
// ulaplus related
wire [ 1:0] up_palsel;
wire [ 2:0] up_paper;
wire [ 2:0] up_ink;
wire up_pixel;
// border sync for 48k/128k emulation
wire border_sync;
// decode video modes
video_modedecode video_modedecode(
.clk(clk),
.pent_vmode(pent_vmode),
.atm_vmode (atm_vmode),
.mode_atm_n_pent (mode_atm_n_pent ),
.mode_zx (mode_zx ),
.mode_p_16c (mode_p_16c ),
.mode_p_hmclr (mode_p_hmclr ),
.mode_a_hmclr (mode_a_hmclr ),
.mode_a_16c (mode_a_16c ),
.mode_a_text (mode_a_text ),
.mode_a_txt_1page(mode_a_txt_1page),
.mode_pixf_14(mode_pixf_14),
.mode_bw(video_bw)
);
// vertical sync generator
video_sync_v video_sync_v(
.clk(clk),
.mode_atm_n_pent(mode_atm_n_pent),
.modes_raster(modes_raster),
.hsync_start(hsync_start),
.line_start(line_start),
.hint_start(hint_start),
.vblank(vblank),
.vsync(vsync),
.vpix(vpix),
.int_start(int_start)
);
// horizontal sync generator
video_sync_h video_sync_h(
.clk(clk),
.mode_atm_n_pent(mode_atm_n_pent),
.mode_a_text (mode_a_text),
.modes_raster (modes_raster ),
.mode_contend_type(mode_contend_type),
.init(1'b0),
.pre_cend(pre_cend),
.cend (cend ),
.hblank(hblank),
.hsync(hsync),
.vpix(vpix),
.hpix(hpix),
.line_start(line_start),
.hsync_start(hsync_start),
.hint_start(hint_start),
.scanin_start(scanin_start),
.fetch_start(fetch_start),
.fetch_end (fetch_end ),
.contend(contend),
.border_sync(border_sync)
);
// address generation
video_addrgen video_addrgen(
.clk(clk),
.video_addr(video_addr),
.video_next(video_next),
.line_start(hsync_start),
.int_start (int_start ),
.vpix (vpix ),
.scr_page(scr_page),
.typos(typos),
.mode_atm_n_pent (mode_atm_n_pent ),
.mode_zx (mode_zx ),
.mode_p_16c (mode_p_16c ),
.mode_p_hmclr (mode_p_hmclr ),
.mode_a_hmclr (mode_a_hmclr ),
.mode_a_16c (mode_a_16c ),
.mode_a_text (mode_a_text ),
.mode_a_txt_1page(mode_a_txt_1page)
);
// data fetch
video_fetch video_fetch(
.clk(clk),
.pre_cend (pre_cend),
.cend (cend ),
.vpix(vpix),
.fetch_start(fetch_start),
.fetch_end (fetch_end ),
.fetch_sync (fetch_sync ),
.video_data (video_data ),
.video_strobe(video_strobe),
.video_go (video_go ),
.pic_bits(pic_bits)
);
// render fetched data to pixels
video_render video_render(
.clk(clk),
.pic_bits(pic_bits),
.fetch_sync(fetch_sync),
.cbeg (cbeg ),
.post_cbeg(post_cbeg),
.pre_cend (pre_cend ),
.cend (cend ),
.int_start(int_start),
.mode_atm_n_pent(mode_atm_n_pent),
.mode_zx (mode_zx ),
.mode_p_16c (mode_p_16c ),
.mode_p_hmclr (mode_p_hmclr ),
.mode_a_hmclr (mode_a_hmclr ),
.mode_a_16c (mode_a_16c ),
.mode_a_text (mode_a_text ),
.mode_pixf_14 (mode_pixf_14 ),
.typos(typos),
.pixels(pixels),
.up_palsel(up_palsel),
.up_paper (up_paper ),
.up_ink (up_ink ),
.up_pixel (up_pixel ),
.fnt_a (fnt_a ),
.fnt_d (fnt_d ),
.fnt_wr(fnt_wr),
.fontrom_readback(fontrom_readback)
);
// combine border and pixels, apply palette
video_palframe video_palframe(
.clk(clk),
.hblank(hblank),
.vblank(vblank),
.hsync_start(hsync_start),
.vsync (vsync ),
.hpix(hpix),
.vpix(vpix),
.pixels(pixels),
.border(zxborder),
.border_sync (border_sync ),
.border_sync_ena(modes_raster[1]),
.atm_palwr (atm_palwr ),
.atm_paldata(atm_paldata),
.atm_paldatalow(atm_paldatalow), //GgRrBb
.pal444_ena(pal444_ena),
.up_palsel(up_palsel),
.up_paper (up_paper ),
.up_ink (up_ink ),
.up_pixel (up_pixel ),
.up_ena (up_ena ),
.up_paladdr(up_paladdr),
.up_paldata(up_paldata),
.up_palwr (up_palwr ),
.modes_raster (modes_raster ),
.color(color),
.palcolor(palcolor) // palette readback
);
// VGA hsync doubling
video_vga_sync_h video_vga_sync_h(
.clk(clk),
.hsync_start(hsync_start),
.modes_raster(modes_raster),
.scanout_start(scanout_start),
.vga_hsync(vga_hsync)
);
// VGA scandoubling
video_vga_double video_vga_double(
.clk(clk),
.hsync_start (hsync_start ),
.scanout_start(scanout_start),
.scanin_start (scanin_start ),
.pix_in(color),
.pix_out(vga_color)
);
// final MUXing of VGA and TV signals
video_outmux video_outmux(
.clk(clk),
.vga_on(vga_on),
.tvcolor(color),
.vgacolor(vga_color),
.vga_hsync(vga_hsync),
.hsync (hsync ),
.vsync (vsync ),
.vred(vred),
.vgrn(vgrn),
.vblu(vblu),
.vhsync(vhsync),
.vvsync(vvsync),
.vcsync(vcsync)
);
endmodule