The method of ram and ROM initialization in FPGA design

FPGA In design RAM and ROM Used as a memory to store variable or immutable types of data , There are different initialization methods according to different usage scenarios .ROM Initialization is usually to load fixed data ,RAM It is declared as unsteady data by default , When initializing, the data can be all 1 Or all 0.

RAM Initialization method of

Method 1： small RAM When resetting, write the initial value according to the address

For small RAM You can directly write the initial value by address during reset , Examples are as follows .

always @(posedge Wr_clk or negedge rst_n)begin
    if (!rst_n) begin 
        Mem[0] <= 24'b0;
        Mem[1] <= 24'b0;
        Mem[2] <= 24'b0;
        Mem[3] <= 24'b0;
        Mem[4]