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Added AXI interface

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This commit is contained in:
Jens True
2018-11-20 17:22:49 +01:00
parent f65b8535e3
commit 1d1217609e
6 changed files with 558 additions and 25 deletions
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23
minized_vga.xdc
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@ -3,17 +3,20 @@
#######################################################################
set_property PACKAGE_PIN L15 [get_ports {PL_VGA_R[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_R[0]}]
set_property PACKAGE_PIN L15 [get_ports {PL_VGA_R}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_R}]
set_property PACKAGE_PIN M15 [get_ports {PL_VGA_G[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_G[0]}]
set_property PACKAGE_PIN M15 [get_ports {PL_VGA_G}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_G}]
set_property PACKAGE_PIN L14 [get_ports {PL_VGA_B[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_B[0]}]
set_property PACKAGE_PIN L14 [get_ports {PL_VGA_B}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_B}]
set_property PACKAGE_PIN K13 [get_ports {PL_VGA_HSYNC[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_HSYNC[0]}]
set_property PACKAGE_PIN K13 [get_ports {PL_VGA_HS}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_HS}]
set_property PACKAGE_PIN L13 [get_ports {PL_VGA_VSYNC[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_VSYNC[0]}]
set_property PACKAGE_PIN L13 [get_ports {PL_VGA_VS}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_VS}]
set_property PACKAGE_PIN N13 [get_ports {PL_VGA_ACTIVE}]
set_property IOSTANDARD LVCMOS33 [get_ports {PL_VGA_ACTIVE}]

111
simplevga_v1_0.v Normal file
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`timescale 1 ns / 1 ps
module simplevga_v1_0 #
(
// Users to add parameters here
// User parameters ends
// Do not modify the parameters beyond this line
// Parameters of Axi Slave Bus Interface S00_AXI
parameter integer C_S00_AXI_DATA_WIDTH = 32,
parameter integer C_S00_AXI_ADDR_WIDTH = 4
)
(
// Users to add ports here
input wire I_PIXEL_CLK,
output wire O_VGA_ACTIVE, //High when drawing is active
output wire O_VGA_HS, // horizontal sync output
output wire O_VGA_VS, // vertical sync output
output wire O_VGA_R, // 1-bit VGA red output
output wire O_VGA_G, // 1-bit VGA green output
output wire O_VGA_B, // 1-bit VGA blue output
// User ports ends
// Do not modify the ports beyond this line
// Ports of Axi Slave Bus Interface S00_AXI
input wire s00_axi_aclk,
input wire s00_axi_aresetn,
input wire [C_S00_AXI_ADDR_WIDTH-1 : 0] s00_axi_awaddr,
input wire [2 : 0] s00_axi_awprot,
input wire s00_axi_awvalid,
output wire s00_axi_awready,
input wire [C_S00_AXI_DATA_WIDTH-1 : 0] s00_axi_wdata,
input wire [(C_S00_AXI_DATA_WIDTH/8)-1 : 0] s00_axi_wstrb,
input wire s00_axi_wvalid,
output wire s00_axi_wready,
output wire [1 : 0] s00_axi_bresp,
output wire s00_axi_bvalid,
input wire s00_axi_bready,
input wire [C_S00_AXI_ADDR_WIDTH-1 : 0] s00_axi_araddr,
input wire [2 : 0] s00_axi_arprot,
input wire s00_axi_arvalid,
output wire s00_axi_arready,
output wire [C_S00_AXI_DATA_WIDTH-1 : 0] s00_axi_rdata,
output wire [1 : 0] s00_axi_rresp,
output wire s00_axi_rvalid,
input wire s00_axi_rready
);
wire [C_S00_AXI_DATA_WIDTH-1:0] reg_x;
wire [C_S00_AXI_DATA_WIDTH-1:0] reg_y;
wire [C_S00_AXI_DATA_WIDTH-1:0] reg_color;
// Instantiation of Axi Bus Interface S00_AXI
simplevga_v1_0_S00_AXI # (
.C_S_AXI_DATA_WIDTH(C_S00_AXI_DATA_WIDTH),
.C_S_AXI_ADDR_WIDTH(C_S00_AXI_ADDR_WIDTH)
) simplevga_v1_0_S00_AXI_inst (
.slave_reg0(reg_x),
.slave_reg1(reg_y),
.slave_reg2(reg_color),
.S_AXI_ACLK(s00_axi_aclk),
.S_AXI_ARESETN(s00_axi_aresetn),
.S_AXI_AWADDR(s00_axi_awaddr),
.S_AXI_AWPROT(s00_axi_awprot),
.S_AXI_AWVALID(s00_axi_awvalid),
.S_AXI_AWREADY(s00_axi_awready),
.S_AXI_WDATA(s00_axi_wdata),
.S_AXI_WSTRB(s00_axi_wstrb),
.S_AXI_WVALID(s00_axi_wvalid),
.S_AXI_WREADY(s00_axi_wready),
.S_AXI_BRESP(s00_axi_bresp),
.S_AXI_BVALID(s00_axi_bvalid),
.S_AXI_BREADY(s00_axi_bready),
.S_AXI_ARADDR(s00_axi_araddr),
.S_AXI_ARPROT(s00_axi_arprot),
.S_AXI_ARVALID(s00_axi_arvalid),
.S_AXI_ARREADY(s00_axi_arready),
.S_AXI_RDATA(s00_axi_rdata),
.S_AXI_RRESP(s00_axi_rresp),
.S_AXI_RVALID(s00_axi_rvalid),
.S_AXI_RREADY(s00_axi_rready)
);
// Add user logic here
wire [9:0] box_x1 = reg_x[9:0];
wire [9:0] box_x2 = reg_x[25:16];
wire [8:0] box_y1 = reg_y[8:0];
wire [8:0] box_y2 = reg_y[24:16];
wire [5:0] box_color = reg_color[5:0];
vgasquare display (
.CLK(s00_axi_aclk), // board clock
.PIXEL_CLK(I_PIXEL_CLK), // Pixel clock: 25Mhz (or 25.125MHz) for VGA
.RST_BTN(s00_axi_aresetn), // reset button
.box_x1(box_x1),
.box_x2(box_x2),
.box_y1(box_y1),
.box_y2(box_y2),
.box_color(box_color), //1 bit for each color Foreground and background
.VGA_ACTIVE(O_VGA_ACTIVE),
.VGA_HS(O_VGA_HS), // horizontal sync output
.VGA_VS(O_VGA_VS), // vertical sync output
.VGA_R(O_VGA_R), // 1-bit VGA red output
.VGA_G(O_VGA_G), // 1-bit VGA green output
.VGA_B(O_VGA_B) // 1-bit VGA blue output
);
// User logic ends
endmodule

409
simplevga_v1_0_S00_AXI.v Normal file
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`timescale 1 ns / 1 ps
module simplevga_v1_0_S00_AXI #
(
// Users to add parameters here
// User parameters ends
// Do not modify the parameters beyond this line
// Width of S_AXI data bus
parameter integer C_S_AXI_DATA_WIDTH = 32,
// Width of S_AXI address bus
parameter integer C_S_AXI_ADDR_WIDTH = 4
)
(
// Users to add ports here
output wire [C_S_AXI_DATA_WIDTH-1:0]slave_reg0,
output wire [C_S_AXI_DATA_WIDTH-1:0]slave_reg1,
output wire [C_S_AXI_DATA_WIDTH-1:0]slave_reg2,
// User ports ends
// Do not modify the ports beyond this line
// Global Clock Signal
input wire S_AXI_ACLK,
// Global Reset Signal. This Signal is Active LOW
input wire S_AXI_ARESETN,
// Write address (issued by master, acceped by Slave)
input wire [C_S_AXI_ADDR_WIDTH-1 : 0] S_AXI_AWADDR,
// Write channel Protection type. This signal indicates the
// privilege and security level of the transaction, and whether
// the transaction is a data access or an instruction access.
input wire [2 : 0] S_AXI_AWPROT,
// Write address valid. This signal indicates that the master signaling
// valid write address and control information.
input wire S_AXI_AWVALID,
// Write address ready. This signal indicates that the slave is ready
// to accept an address and associated control signals.
output wire S_AXI_AWREADY,
// Write data (issued by master, acceped by Slave)
input wire [C_S_AXI_DATA_WIDTH-1 : 0] S_AXI_WDATA,
// Write strobes. This signal indicates which byte lanes hold
// valid data. There is one write strobe bit for each eight
// bits of the write data bus.
input wire [(C_S_AXI_DATA_WIDTH/8)-1 : 0] S_AXI_WSTRB,
// Write valid. This signal indicates that valid write
// data and strobes are available.
input wire S_AXI_WVALID,
// Write ready. This signal indicates that the slave
// can accept the write data.
output wire S_AXI_WREADY,
// Write response. This signal indicates the status
// of the write transaction.
output wire [1 : 0] S_AXI_BRESP,
// Write response valid. This signal indicates that the channel
// is signaling a valid write response.
output wire S_AXI_BVALID,
// Response ready. This signal indicates that the master
// can accept a write response.
input wire S_AXI_BREADY,
// Read address (issued by master, acceped by Slave)
input wire [C_S_AXI_ADDR_WIDTH-1 : 0] S_AXI_ARADDR,
// Protection type. This signal indicates the privilege
// and security level of the transaction, and whether the
// transaction is a data access or an instruction access.
input wire [2 : 0] S_AXI_ARPROT,
// Read address valid. This signal indicates that the channel
// is signaling valid read address and control information.
input wire S_AXI_ARVALID,
// Read address ready. This signal indicates that the slave is
// ready to accept an address and associated control signals.
output wire S_AXI_ARREADY,
// Read data (issued by slave)
output wire [C_S_AXI_DATA_WIDTH-1 : 0] S_AXI_RDATA,
// Read response. This signal indicates the status of the
// read transfer.
output wire [1 : 0] S_AXI_RRESP,
// Read valid. This signal indicates that the channel is
// signaling the required read data.
output wire S_AXI_RVALID,
// Read ready. This signal indicates that the master can
// accept the read data and response information.
input wire S_AXI_RREADY
);
// AXI4LITE signals
reg [C_S_AXI_ADDR_WIDTH-1 : 0] axi_awaddr;
reg axi_awready;
reg axi_wready;
reg [1 : 0] axi_bresp;
reg axi_bvalid;
reg [C_S_AXI_ADDR_WIDTH-1 : 0] axi_araddr;
reg axi_arready;
reg [C_S_AXI_DATA_WIDTH-1 : 0] axi_rdata;
reg [1 : 0] axi_rresp;
reg axi_rvalid;
// Example-specific design signals
// local parameter for addressing 32 bit / 64 bit C_S_AXI_DATA_WIDTH
// ADDR_LSB is used for addressing 32/64 bit registers/memories
// ADDR_LSB = 2 for 32 bits (n downto 2)
// ADDR_LSB = 3 for 64 bits (n downto 3)
localparam integer ADDR_LSB = (C_S_AXI_DATA_WIDTH/32) + 1;
localparam integer OPT_MEM_ADDR_BITS = 1;
//----------------------------------------------
//-- Signals for user logic register space example
//------------------------------------------------
//-- Number of Slave Registers 4
reg [C_S_AXI_DATA_WIDTH-1:0] slv_reg0;
reg [C_S_AXI_DATA_WIDTH-1:0] slv_reg1;
reg [C_S_AXI_DATA_WIDTH-1:0] slv_reg2;
reg [C_S_AXI_DATA_WIDTH-1:0] slv_reg3;
wire slv_reg_rden;
wire slv_reg_wren;
reg [C_S_AXI_DATA_WIDTH-1:0] reg_data_out;
integer byte_index;
reg aw_en;
// I/O Connections assignments
assign slave_reg0 = slv_reg0;
assign slave_reg1 = slv_reg1;
assign slave_reg2 = slv_reg2;
// End custom assignments
assign S_AXI_AWREADY = axi_awready;
assign S_AXI_WREADY = axi_wready;
assign S_AXI_BRESP = axi_bresp;
assign S_AXI_BVALID = axi_bvalid;
assign S_AXI_ARREADY = axi_arready;
assign S_AXI_RDATA = axi_rdata;
assign S_AXI_RRESP = axi_rresp;
assign S_AXI_RVALID = axi_rvalid;
// Implement axi_awready generation
// axi_awready is asserted for one S_AXI_ACLK clock cycle when both
// S_AXI_AWVALID and S_AXI_WVALID are asserted. axi_awready is
// de-asserted when reset is low.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_awready <= 1'b0;
aw_en <= 1'b1;
end
else
begin
if (~axi_awready && S_AXI_AWVALID && S_AXI_WVALID && aw_en)
begin
// slave is ready to accept write address when
// there is a valid write address and write data
// on the write address and data bus. This design
// expects no outstanding transactions.
axi_awready <= 1'b1;
aw_en <= 1'b0;
end
else if (S_AXI_BREADY && axi_bvalid)
begin
aw_en <= 1'b1;
axi_awready <= 1'b0;
end
else
begin
axi_awready <= 1'b0;
end
end
end
// Implement axi_awaddr latching
// This process is used to latch the address when both
// S_AXI_AWVALID and S_AXI_WVALID are valid.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_awaddr <= 0;
end
else
begin
if (~axi_awready && S_AXI_AWVALID && S_AXI_WVALID && aw_en)
begin
// Write Address latching
axi_awaddr <= S_AXI_AWADDR;
end
end
end
// Implement axi_wready generation
// axi_wready is asserted for one S_AXI_ACLK clock cycle when both
// S_AXI_AWVALID and S_AXI_WVALID are asserted. axi_wready is
// de-asserted when reset is low.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_wready <= 1'b0;
end
else
begin
if (~axi_wready && S_AXI_WVALID && S_AXI_AWVALID && aw_en )
begin
// slave is ready to accept write data when
// there is a valid write address and write data
// on the write address and data bus. This design
// expects no outstanding transactions.
axi_wready <= 1'b1;
end
else
begin
axi_wready <= 1'b0;
end
end
end
// Implement memory mapped register select and write logic generation
// The write data is accepted and written to memory mapped registers when
// axi_awready, S_AXI_WVALID, axi_wready and S_AXI_WVALID are asserted. Write strobes are used to
// select byte enables of slave registers while writing.
// These registers are cleared when reset (active low) is applied.
// Slave register write enable is asserted when valid address and data are available
// and the slave is ready to accept the write address and write data.
assign slv_reg_wren = axi_wready && S_AXI_WVALID && axi_awready && S_AXI_AWVALID;
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
slv_reg0 <= 0;
slv_reg1 <= 0;
slv_reg2 <= 0;
slv_reg3 <= 0;
end
else begin
if (slv_reg_wren)
begin
case ( axi_awaddr[ADDR_LSB+OPT_MEM_ADDR_BITS:ADDR_LSB] )
2'h0:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 0
slv_reg0[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
2'h1:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 1
slv_reg1[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
2'h2:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 2
slv_reg2[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
2'h3:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 3
slv_reg3[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
default : begin
slv_reg0 <= slv_reg0;
slv_reg1 <= slv_reg1;
slv_reg2 <= slv_reg2;
slv_reg3 <= slv_reg3;
end
endcase
end
end
end
// Implement write response logic generation
// The write response and response valid signals are asserted by the slave
// when axi_wready, S_AXI_WVALID, axi_wready and S_AXI_WVALID are asserted.
// This marks the acceptance of address and indicates the status of
// write transaction.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_bvalid <= 0;
axi_bresp <= 2'b0;
end
else
begin
if (axi_awready && S_AXI_AWVALID && ~axi_bvalid && axi_wready && S_AXI_WVALID)
begin
// indicates a valid write response is available
axi_bvalid <= 1'b1;
axi_bresp <= 2'b0; // 'OKAY' response
end // work error responses in future
else
begin
if (S_AXI_BREADY && axi_bvalid)
//check if bready is asserted while bvalid is high)
//(there is a possibility that bready is always asserted high)
begin
axi_bvalid <= 1'b0;
end
end
end
end
// Implement axi_arready generation
// axi_arready is asserted for one S_AXI_ACLK clock cycle when
// S_AXI_ARVALID is asserted. axi_awready is
// de-asserted when reset (active low) is asserted.
// The read address is also latched when S_AXI_ARVALID is
// asserted. axi_araddr is reset to zero on reset assertion.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_arready <= 1'b0;
axi_araddr <= 32'b0;
end
else
begin
if (~axi_arready && S_AXI_ARVALID)
begin
// indicates that the slave has acceped the valid read address
axi_arready <= 1'b1;
// Read address latching
axi_araddr <= S_AXI_ARADDR;
end
else
begin
axi_arready <= 1'b0;
end
end
end
// Implement axi_arvalid generation
// axi_rvalid is asserted for one S_AXI_ACLK clock cycle when both
// S_AXI_ARVALID and axi_arready are asserted. The slave registers
// data are available on the axi_rdata bus at this instance. The
// assertion of axi_rvalid marks the validity of read data on the
// bus and axi_rresp indicates the status of read transaction.axi_rvalid
// is deasserted on reset (active low). axi_rresp and axi_rdata are
// cleared to zero on reset (active low).
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_rvalid <= 0;
axi_rresp <= 0;
end
else
begin
if (axi_arready && S_AXI_ARVALID && ~axi_rvalid)
begin
// Valid read data is available at the read data bus
axi_rvalid <= 1'b1;
axi_rresp <= 2'b0; // 'OKAY' response
end
else if (axi_rvalid && S_AXI_RREADY)
begin
// Read data is accepted by the master
axi_rvalid <= 1'b0;
end
end
end
// Implement memory mapped register select and read logic generation
// Slave register read enable is asserted when valid address is available
// and the slave is ready to accept the read address.
assign slv_reg_rden = axi_arready & S_AXI_ARVALID & ~axi_rvalid;
always @(*)
begin
// Address decoding for reading registers
case ( axi_araddr[ADDR_LSB+OPT_MEM_ADDR_BITS:ADDR_LSB] )
2'h0 : reg_data_out <= slv_reg0;
2'h1 : reg_data_out <= slv_reg1;
2'h2 : reg_data_out <= slv_reg2;
2'h3 : reg_data_out <= slv_reg3;
default : reg_data_out <= 0;
endcase
end
// Output register or memory read data
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_rdata <= 0;
end
else
begin
// When there is a valid read address (S_AXI_ARVALID) with
// acceptance of read address by the slave (axi_arready),
// output the read dada
if (slv_reg_rden)
begin
axi_rdata <= reg_data_out; // register read data
end
end
end
// Add user logic here
// User logic ends
endmodule

11
userland.c Normal file
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@ -0,0 +1,11 @@
SIMPLEVGA_mWriteReg(XPAR_SIMPLEVGA_0_S00_AXI_BASEADDR, SIMPLEVGA_S00_AXI_SLV_REG0_OFFSET, 0xFFFFFFFF);
SIMPLEVGA_mWriteReg(XPAR_SIMPLEVGA_0_S00_AXI_BASEADDR, SIMPLEVGA_S00_AXI_SLV_REG1_OFFSET, 0xFFFFFFFF);
SIMPLEVGA_mWriteReg(XPAR_SIMPLEVGA_0_S00_AXI_BASEADDR, SIMPLEVGA_S00_AXI_SLV_REG2_OFFSET, 0xFFFFFFFF);
unsigned long x = 1;
while(1) {
for(x = 1; x < 100; x++) {
unsigned long xreg = ((640-x) << 16) + x;
SIMPLEVGA_mWriteReg(XPAR_SIMPLEVGA_0_S00_AXI_BASEADDR, SIMPLEVGA_S00_AXI_SLV_REG0_OFFSET, x);
//usleep(1000000);
}
}

22
vga640x480.v
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@ -54,25 +54,23 @@ module vga640x480(
// animate: high for one tick at the end of the final active pixel line
assign o_animate = ((v_count == VA_END - 1) & (h_count == LINE));
always @ (posedge i_clk)
always @ (posedge i_pix_stb)
begin
if (i_rst) // reset to start of frame
begin
h_count <= 0;
v_count <= 0;
end
if (i_pix_stb) // once per pixel
begin
if (h_count == LINE) // end of line
begin
h_count <= 0;
v_count <= v_count + 1;
end
else
h_count <= h_count + 1;
if (v_count == SCREEN) // end of screen
v_count <= 0;
if (h_count == LINE) // end of line
begin
h_count <= 0;
v_count <= v_count + 1;
end
else
h_count <= h_count + 1;
if (v_count == SCREEN) // end of screen
v_count <= 0;
end
endmodule

5
vgasquare.v
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@ -14,6 +14,7 @@ module vgasquare(
input wire [8:0] box_y1,
input wire [8:0] box_y2,
input wire [5:0] box_color, //1 bit for each color Foreground and background
output wire VGA_ACTIVE, //High when drawing is active
output wire VGA_HS, // horizontal sync output
output wire VGA_VS, // vertical sync output
output wire VGA_R, // 1-bit VGA red output
@ -30,6 +31,7 @@ module vgasquare(
.i_clk(CLK),
.i_pix_stb(PIXEL_CLK),
.i_rst(rst),
.o_active(VGA_ACTIVE),
.o_hs(VGA_HS),
.o_vs(VGA_VS),
.o_x(x),
@ -37,8 +39,7 @@ module vgasquare(
);
// Draw one square
wire square;
assign square = ((x > box_x1) & (y > box_y1) & (x < box_x2) & (y < box_y2)) ? 1 : 0; //Is box within range?
wire square = ((x > box_x1) & (y > box_y1) & (x < box_x2) & (y < box_y2)) ? 1 : 0; //Is box within range?
assign VGA_R = square ? box_color[0] : box_color[3]; // Set R (Foreground and then background)