To make your [FPGA](https://www.ampheo.com/c/fpgas-field-programmable-gate-array) 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: ![FASTPCQIWI0TZ4P](https://hackmd.io/_uploads/Hyt0BiAQlx.jpg) **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](https://www.vemeko.com/product/#Intel))** Modern [FPGAs](https://www.ampheoelec.de/c/fpgas-field-programmable-gate-array) 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** ![企业微信截图_20250617161646](https://hackmd.io/_uploads/S11KVoRmll.png) **Summary** ![企业微信截图_20250617161706](https://hackmd.io/_uploads/B1N9EoCXeg.png)