To make your FPGA output slower, you typically reduce the frequency of the signal you're generating. This is often done using a clock divider or counters in your HDL (VHDL or Verilog). Here's how to approach it:

Common Methods to Slow Down Output on FPGA
1. Use a Clock Divider
Divide the system clock to get a slower signal:

Verilog Example:

verilog

module clock_divider (
    input wire clk,         // Input clock (e.g., 50 MHz)
    output reg slow_clk     // Slower output clock
);
    reg [24:0] count = 0;

    always @(posedge clk) begin
        count <= count + 1;
        slow_clk <= count[24];  // Output toggles every 2^24 cycles
    end
endmodule

This divides the frequency by 2^25, producing a very slow square wave.

2. Use a Counter for Timing Control
If you're toggling an output (e.g., LED), use a counter to delay the toggle:

verilog

module led_blink (
    input wire clk,
    output reg led
);
    reg [23:0] counter = 0;

    always @(posedge clk) begin
        counter <= counter + 1;
        if (counter == 24_000_000) begin  // Adjust based on your clock speed
            led <= ~led;
            counter <= 0;
        end
    end
endmodule

3. Use a PLL or Clock Management Block (e.g., in Xilinx or Intel FPGAs)
Modern FPGAs have Clock Management Tiles (CMTs) or PLL blocks to generate custom clock frequencies.

• In Xilinx Vivado: Use Clocking Wizard to generate a slower clock.
• In Intel Quartus: Use the ALTPLL IP core.

This is better for precise or multiple clock domains.

Things to Watch Out For

Summary