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/*
COOLGIRL Multicart branch 5.x
*/
module CoolGirl # (
`include "../CoolGirl_config.vh"
)
(
input m2,
input romsel,
input cpu_rw_in,
input [14:0] cpu_addr_in,
inout [7:0] cpu_data_in,
output [26:13] cpu_addr_out,
output [14:13] sram_addr_out,
output cpu_shifers_oe,
output cpu_dir,
output flash_we,
output flash_oe,
output flash_ce,
output sram_ce,
output sram_we,
output sram_oe,
input ppu_rd_in,
input ppu_wr_in,
input [13:3] ppu_addr_in,
output [18:10] ppu_addr_out,
output ppu_rd_out,
output ppu_wr_out,
output ppu_ciram_a10,
inout ppu_not_a13,
output ppu_ciram_ce,
output irq
);
reg [3:0] new_dendy_init = 4'b1111;
reg [1:0] new_dendy_init_a13l = 2'b11;
reg [1:0] new_dendy_init_a13h = 2'b11;
wire new_dendy_init_finished = new_dendy_init == 0;
reg new_dendy = 0;
assign cpu_shifers_oe = 1'b0;
assign cpu_addr_out[26:13] = {prg_base[26:14] | (prg_addr_mapped[20:14] & ~prg_mask[20:14]), prg_addr_mapped[13]};
assign sram_addr_out[14:13] = sram_page[1:0];
assign ppu_addr_out[18:10] = ext_ntram_access
? {7'b1111111, ppu_addr_in[11:10]}
: {{~chr_addr_mapped[18], chr_addr_mapped[17:13]} & ~chr_mask[18:13], chr_addr_mapped[12:10]};
assign cpu_data_in = cpu_data_out_enabled ? cpu_data_out : 8'bZZZZZZZZ;
wire flash_ce_w = ~(~romsel | (m2 & map_rom_on_6000 & cpu_addr_in[14] & cpu_addr_in[13]));
assign flash_ce = flash_ce_w | cpu_data_out_enabled;
assign flash_oe = ~cpu_rw_in | flash_ce_w;
assign flash_we = cpu_rw_in | flash_ce_w | ~prg_write_enabled;
wire sram_ce_w = ~(cpu_addr_in[14] & cpu_addr_in[13] & m2 & romsel & sram_enabled & ~map_rom_on_6000);
assign sram_ce = sram_ce_w | cpu_data_out_enabled;
assign sram_we = cpu_rw_in | sram_ce_w;
assign sram_oe = ~cpu_rw_in | sram_ce_w;
assign cpu_dir = (~cpu_rw_in | flash_ce_w) & (~cpu_rw_in | sram_ce_w) & ~cpu_data_out_enabled;
assign ppu_rd_out = ppu_rd_in | (ppu_addr_in[13] & ~ext_ntram_access);
assign ppu_wr_out = ppu_wr_in | ((ppu_addr_in[13] | ~chr_write_enabled) & ~ext_ntram_access);
wire ext_ntram_access = ENABLE_FOUR_SCREEN && four_screen && ppu_addr_in[13] && ~ppu_addr_in[12]; // four-screen and $2000-$2FFF accessed
assign ppu_ciram_ce = new_dendy_init_finished ?
(new_dendy ? 1'bZ : // not used by new famiclones
ext_ntram_access ? 1'b1 : // disable internal NTRAM
~ppu_addr_in[13] /*1'bZ*/) // enable it otherwise
: 1'b0; // ground it while powering on for new famiclones
assign ppu_not_a13 = new_dendy_init_finished ? 1'bZ : 1'b0; // ground it while powering on for new famiclones
always @ (posedge m2)
begin
if (!new_dendy_init_finished)
new_dendy_init = new_dendy_init - 1'b1;
end
always @ (negedge ppu_rd_in)
begin
if (new_dendy_init_finished)
begin
if ((new_dendy_init_a13l != 0) &&
(new_dendy_init_a13h != 0) &&
(ppu_addr_in[13] != ~ppu_not_a13))
new_dendy = 1;
if (~ppu_addr_in[13] && new_dendy_init_a13l != 0) new_dendy_init_a13l = new_dendy_init_a13l - 1'b1;
if (ppu_addr_in[13] && new_dendy_init_a13h != 0) new_dendy_init_a13h = new_dendy_init_a13h - 1'b1;
end
end
`include "../CoolGirl_mappers.vh"
endmodule
|
