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TSConf_MiST/rtl/common/zports.v
2020-05-11 23:17:53 +08:00

470 lines
13 KiB
Verilog

// PentEvo project (c) NedoPC 2008-2010
module zports
(
input clk,
input [7:0] din,
output reg [7:0] dout,
output dataout,
input [15:0] a,
input rst, // system reset
input opfetch,
input rd,
input wr,
input rdwr,
input iorq,
input iorq_s,
input iord,
input iord_s,
input iowr,
input iowr_s,
input iordwr,
input iordwr_s,
output porthit, // when internal port hit occurs, this is 1, else 0; used for iorq1_n iorq2_n on zxbus
output external_port, // asserts for AY and VG93 accesses
output zborder_wr,
output border_wr,
output zvpage_wr,
output vpage_wr,
output vconf_wr,
output gx_offsl_wr,
output gx_offsh_wr,
output gy_offsl_wr,
output gy_offsh_wr,
output t0x_offsl_wr,
output t0x_offsh_wr,
output t0y_offsl_wr,
output t0y_offsh_wr,
output t1x_offsl_wr,
output t1x_offsh_wr,
output t1y_offsl_wr,
output t1y_offsh_wr,
output tsconf_wr,
output palsel_wr,
output tmpage_wr,
output t0gpage_wr,
output t1gpage_wr,
output sgpage_wr,
output hint_beg_wr ,
output vint_begl_wr,
output vint_begh_wr,
output [31:0] xt_page,
output reg [4:0] fmaddr,
input regs_we,
output reg [7:0] sysconf,
output reg [7:0] memconf,
output reg [3:0] cacheconf,
output reg [7:0] fddvirt,
output [8:0] dmaport_wr,
input dma_act,
output reg [1:0] dmawpdev,
output reg [7:0] intmask,
input dos,
input vdos,
output vdos_on,
output vdos_off,
output ay_bdir,
output ay_bc1,
output covox_wr,
output beeper_wr,
input tape_read,
input [4:0] keys_in, // keys (port FE)
input [7:0] mus_in, // mouse (xxDF)
input [5:0] kj_in,
input vg_intrq,
input vg_drq, // from vg93 module - drq + irq read
output vg_cs_n,
output vg_wrFF,
output [1:0] drive_sel, // disk drive selection
// SPI
output sdcs_n,
output sd_start,
output [7:0] sd_datain,
input [7:0] sd_dataout,
// WAIT-ports related
output reg [7:0] wait_addr,
output wait_start_gluclock, // begin wait from some ports
output wait_start_comport, //
output reg [7:0] wait_write,
input [7:0] wait_read
);
assign sdcs_n = spi_cs_n[0];
localparam FDR_VER = 1'b0;
localparam VDAC_VER = 3'h3;
localparam PORTFE = 8'hFE;
localparam PORTFD = 8'hFD;
localparam PORTXT = 8'hAF;
localparam PORTF7 = 8'hF7;
localparam COVOX = 8'hFB;
localparam VGCOM = 8'h1F;
localparam VGTRK = 8'h3F;
localparam VGSEC = 8'h5F;
localparam VGDAT = 8'h7F;
localparam VGSYS = 8'hFF;
localparam KJOY = 8'h1F;
localparam KMOUSE = 8'hDF;
localparam SDCFG = 8'h77;
localparam SDDAT = 8'h57;
localparam COMPORT = 8'hEF; // F8EF..FFEF - rs232 ports
wire [7:0] loa = a[7:0];
wire [7:0] hoa = regs_we ? a[7:0] : a[15:8];
assign porthit = ((loa==PORTFE) || (loa==PORTXT) || (loa==PORTFD) || (loa==COVOX))
|| ((loa==PORTF7) && !dos)
|| ((vg_port || vgsys_port) && (dos || open_vg))
|| ((loa==KJOY) && !dos && !open_vg)
|| (loa==KMOUSE)
|| (((loa==SDCFG) || (loa==SDDAT)) && (!dos || vdos))
|| (loa==COMPORT);
wire vg_port = (loa==VGCOM) || (loa==VGTRK) || (loa==VGSEC) || (loa==VGDAT);
wire vgsys_port = (loa==VGSYS);
assign external_port = ((loa==PORTFD) && a[15]) // AY
|| (((loa==VGCOM) || (loa==VGTRK) || (loa==VGSEC) || (loa==VGDAT)) && (dos || open_vg));
assign dataout = porthit && iord && (~external_port);
reg iowr_reg;
reg iord_reg;
reg port_wr;
reg port_rd;
always @(posedge clk) begin
iowr_reg <= iowr;
port_wr <= (!iowr_reg && iowr);
iord_reg <= iord;
port_rd <= (!iord_reg && iord);
end
// reading ports
always @(*) begin
case (loa)
PORTFE:
dout = {1'b1, tape_read, 1'b0, keys_in};
PORTXT:
begin
case (hoa)
XSTAT:
dout = {1'b0, pwr_up_reg, FDR_VER, 2'b0, VDAC_VER};
DMASTAT:
dout = {dma_act, 7'b0};
RAMPAGE + 8'd2, RAMPAGE + 8'd3:
dout = rampage[hoa[1:0]];
default:
dout = 8'hFF;
endcase
end
VGSYS:
dout = {vg_intrq, vg_drq, 6'b111111};
KJOY:
dout = {2'b00, kj_in};
KMOUSE:
dout = mus_in;
SDCFG:
dout = 8'h00; // always SD inserted, SD is in R/W mode
SDDAT:
dout = sd_dataout;
PORTF7:
begin
if (!a[14] && (a[8] ^ dos) && gluclock_on) dout = wait_read; // $BFF7 - data i/o
else dout = 8'hFF; // any other $xxF7 port
end
COMPORT:
dout = wait_read; // $F8EF..$FFEF
default:
dout = 8'hFF;
endcase
end
// power-up
// This bit is loaded as 1 while FPGA is configured
// and automatically reset to 0 after STATUS port reading
reg pwr_up_reg;
reg pwr_up = 1;
always @(posedge clk) begin
if (iord_s & (loa == PORTXT) & (hoa == XSTAT)) begin
pwr_up_reg <= pwr_up;
pwr_up <= 1'b0;
end
end
// writing ports
//#nnAF
localparam VCONF = 8'h00;
localparam VPAGE = 8'h01;
localparam GXOFFSL = 8'h02;
localparam GXOFFSH = 8'h03;
localparam GYOFFSL = 8'h04;
localparam GYOFFSH = 8'h05;
localparam TSCONF = 8'h06;
localparam PALSEL = 8'h07;
localparam XBORDER = 8'h0F;
localparam T0XOFFSL = 8'h40;
localparam T0XOFFSH = 8'h41;
localparam T0YOFFSL = 8'h42;
localparam T0YOFFSH = 8'h43;
localparam T1XOFFSL = 8'h44;
localparam T1XOFFSH = 8'h45;
localparam T1YOFFSL = 8'h46;
localparam T1YOFFSH = 8'h47;
localparam RAMPAGE = 8'h10; // this covers #10-#13
localparam FMADDR = 8'h15;
localparam TMPAGE = 8'h16;
localparam T0GPAGE = 8'h17;
localparam T1GPAGE = 8'h18;
localparam SGPAGE = 8'h19;
localparam DMASADDRL = 8'h1A;
localparam DMASADDRH = 8'h1B;
localparam DMASADDRX = 8'h1C;
localparam DMADADDRL = 8'h1D;
localparam DMADADDRH = 8'h1E;
localparam DMADADDRX = 8'h1F;
localparam SYSCONF = 8'h20;
localparam MEMCONF = 8'h21;
localparam HSINT = 8'h22;
localparam VSINTL = 8'h23;
localparam VSINTH = 8'h24;
localparam DMAWPD = 8'h25;
localparam DMALEN = 8'h26;
localparam DMACTRL = 8'h27;
localparam DMANUM = 8'h28;
localparam FDDVIRT = 8'h29;
localparam INTMASK = 8'h2A;
localparam CACHECONF = 8'h2B;
localparam DMAWPA = 8'h2D;
localparam XSTAT = 8'h00;
localparam DMASTAT = 8'h27;
assign dmaport_wr[0] = portxt_wr && (hoa == DMASADDRL);
assign dmaport_wr[1] = portxt_wr && (hoa == DMASADDRH);
assign dmaport_wr[2] = portxt_wr && (hoa == DMASADDRX);
assign dmaport_wr[3] = portxt_wr && (hoa == DMADADDRL);
assign dmaport_wr[4] = portxt_wr && (hoa == DMADADDRH);
assign dmaport_wr[5] = portxt_wr && (hoa == DMADADDRX);
assign dmaport_wr[6] = portxt_wr && (hoa == DMALEN);
assign dmaport_wr[7] = portxt_wr && (hoa == DMACTRL);
assign dmaport_wr[8] = portxt_wr && (hoa == DMANUM);
assign zborder_wr = portfe_wr;
assign border_wr = (portxt_wr && (hoa == XBORDER));
assign zvpage_wr = p7ffd_wr;
assign vpage_wr = (portxt_wr && (hoa == VPAGE ));
assign vconf_wr = (portxt_wr && (hoa == VCONF ));
assign gx_offsl_wr = (portxt_wr && (hoa == GXOFFSL));
assign gx_offsh_wr = (portxt_wr && (hoa == GXOFFSH));
assign gy_offsl_wr = (portxt_wr && (hoa == GYOFFSL));
assign gy_offsh_wr = (portxt_wr && (hoa == GYOFFSH));
assign t0x_offsl_wr = (portxt_wr && (hoa == T0XOFFSL));
assign t0x_offsh_wr = (portxt_wr && (hoa == T0XOFFSH));
assign t0y_offsl_wr = (portxt_wr && (hoa == T0YOFFSL));
assign t0y_offsh_wr = (portxt_wr && (hoa == T0YOFFSH));
assign t1x_offsl_wr = (portxt_wr && (hoa == T1XOFFSL));
assign t1x_offsh_wr = (portxt_wr && (hoa == T1XOFFSH));
assign t1y_offsl_wr = (portxt_wr && (hoa == T1YOFFSL));
assign t1y_offsh_wr = (portxt_wr && (hoa == T1YOFFSH));
assign tsconf_wr = (portxt_wr && (hoa == TSCONF));
assign palsel_wr = (portxt_wr && (hoa == PALSEL));
assign tmpage_wr = (portxt_wr && (hoa == TMPAGE));
assign t0gpage_wr = (portxt_wr && (hoa == T0GPAGE));
assign t1gpage_wr = (portxt_wr && (hoa == T1GPAGE));
assign sgpage_wr = (portxt_wr && (hoa == SGPAGE));
assign hint_beg_wr = (portxt_wr && (hoa == HSINT ));
assign vint_begl_wr = (portxt_wr && (hoa == VSINTL));
assign vint_begh_wr = (portxt_wr && (hoa == VSINTH));
assign beeper_wr = portfe_wr;
wire portfe_wr = (loa==PORTFE) && iowr_s;
assign covox_wr = (loa==COVOX) && iowr_s;
wire portxt_wr = ((loa==PORTXT) && iowr_s) || regs_we;
reg [7:0] rampage[0:3];
assign xt_page = {rampage[3], rampage[2], rampage[1], rampage[0]};
wire lock128 = lock128_3 ? 1'b0 : (lock128_2 ? m1_lock128 : memconf[6]);
wire lock128_2 = memconf[7:6] == 2'b10; // mode 2
wire lock128_3 = memconf[7:6] == 2'b11; // mode 3
reg m1_lock128;
always @(posedge clk) if (opfetch) m1_lock128 <= !(din[7] ^ din[6]);
always @(posedge clk) begin
if (rst) begin
fmaddr[4] <= 1'b0;
intmask <= 8'b1;
fddvirt <= 8'b0;
sysconf <= 8'h00; // 3.5 MHz
memconf <= 8'h04; // no map
cacheconf <= 4'h0; // no cache
rampage[0]<= 8'h00;
rampage[1]<= 8'h05;
rampage[2]<= 8'h02;
rampage[3]<= 8'h00;
end
else if (p7ffd_wr) begin
memconf[0] <= din[4];
rampage[3] <= {2'b0, lock128_3 ? {din[5], din[7:6]} : ({1'b0, lock128 ? 2'b0 : din[7:6]}), din[2:0]};
end
else if (portxt_wr) begin
if (hoa[7:2] == RAMPAGE[7:2]) rampage[hoa[1:0]] <= din;
if (hoa == FMADDR) fmaddr <= din[4:0];
if (hoa == SYSCONF) begin
sysconf <= din;
cacheconf <= {4{din[2]}};
end
if (hoa == DMAWPD) dmawpdev <= din[1:0];
if (hoa == CACHECONF) cacheconf <= din[3:0];
if (hoa == MEMCONF) memconf <= din;
if (hoa == FDDVIRT) fddvirt <= din;
if (hoa == INTMASK) intmask <= din;
end
end
// 7FFD port
wire p7ffd_wr = !a[15] && (loa==PORTFD) && iowr_s && !lock48;
reg lock48;
always @(posedge clk) begin
if (rst) lock48 <= 1'b0;
else if (p7ffd_wr && !lock128_3) lock48 <= din[5];
end
// AY control
wire ay_hit = (loa==PORTFD) & a[15];
assign ay_bc1 = ay_hit & a[14] & iordwr;
assign ay_bdir = ay_hit & iowr;
// VG93
wire [3:0] fddvrt = fddvirt[3:0];
wire virt_vg = fddvrt[drive_sel_raw];
wire open_vg = fddvirt[7];
assign drive_sel = {drive_sel_raw[1], drive_sel_raw[0]};
wire vg_wen = (dos || open_vg) && !vdos && !virt_vg;
assign vg_cs_n = !(iordwr && vg_port && vg_wen);
assign vg_wrFF = iowr_s && vgsys_port && vg_wen;
wire vg_wrDS = iowr_s && vgsys_port && (dos || open_vg);
assign vdos_on = iordwr_s && (vg_port || vgsys_port) && dos && !vdos && virt_vg;
assign vdos_off = iordwr_s && vg_port && vdos;
// write drive number
reg [1:0] drive_sel_raw;
always @(posedge clk) if (vg_wrDS) drive_sel_raw <= din[1:0];
// SD card (Z-controller compatible)
wire sdcfg_wr;
wire sddat_wr;
wire sddat_rd;
reg [1:0] spi_cs_n;
assign sdcfg_wr = ((loa==SDCFG) && iowr_s && (!dos || vdos));
assign sddat_wr = ((loa==SDDAT) && iowr_s && (!dos || vdos));
assign sddat_rd = ((loa==SDDAT) && iord_s);
// SDCFG write - sdcs_n control
always @(posedge clk) begin
if (rst) spi_cs_n <= 2'b11;
else if (sdcfg_wr) spi_cs_n <= {~din[2], din[1]};
end
// start signal for SPI module with resyncing to fclk
assign sd_start = sddat_wr || sddat_rd;
// data for SPI module
assign sd_datain = wr ? din : 8'hFF;
// xxF7
wire portf7_wr = ((loa==PORTF7) && (a[8]==1'b1) && port_wr && (!dos || vdos));
wire portf7_rd = ((loa==PORTF7) && (a[8]==1'b1) && port_rd && (!dos || vdos));
// EFF7 port
reg [7:0] peff7;
always @(posedge clk) begin
if (rst) peff7 <= 8'h00;
else if (!a[12] && portf7_wr && !dos) peff7 <= din; // #EEF7 in dos is not accessible
end
// gluclock ports
wire gluclock_on = peff7[7] || dos; // in dos mode EEF7 is not accessible, gluclock access is ON in dos mode.
// comports
wire comport_wr = ((loa == COMPORT) && port_wr);
wire comport_rd = ((loa == COMPORT) && port_rd);
// write to wait registers
always @(posedge clk) begin
// gluclocks
if (gluclock_on && portf7_wr) begin
if (!a[14]) wait_write <= din; // $BFF7 - data reg
if (!a[13]) wait_addr <= din; // $DFF7 - addr reg
end
// com ports
if (comport_wr) wait_write <= din; // $xxEF
if (comport_wr || comport_rd) wait_addr <= a[15:8];
if ((loa==PORTXT) && (hoa == DMAWPA)) wait_addr <= din;
end
// wait from wait registers
// ACHTUNG!!!! here portxx_wr are ON Z80 CLOCK! logic must change when moving to clk strobes
assign wait_start_gluclock = (gluclock_on && !a[14] && (portf7_rd || portf7_wr)); // $BFF7 - gluclock r/w
assign wait_start_comport = (comport_rd || comport_wr);
endmodule