FPGA开发板 SD卡例程 上电至少等待74个同步时钟周期, 为什么POWER_ON_NUM = 5000 这不成了等待5000个时钟了吗
//上电等待稳定计数器
always @(posedge div_clk or negedge rst_n) begin
if(!rst_n)
poweron_cnt <= 13'd0;
else if(cur_state == st_idle) begin
if(poweron_cnt < POWER_ON_NUM) // 5000个clk??
poweron_cnt <= poweron_cnt + 1'b1;
end
else
poweron_cnt <= 13'd0;
end |