IO_BUFFER_TYPE不像其他属性,可在XDC约束文件中使用,该属性只能用于RTL代码中,用法示例:(* IO_BUFFER_TYPE=VALUE*) input in,VALUE只能为NONE或YES。 2.2 工程代码 moduleDIRECT_CE_RS(d,ce,clk,out0);(*IO_BUFFER_TYPE="NONE"*)inputd;inputce,clk;outputout0;regout0;always@(posedge...
如果不想自动插入BUFFER,则可使用属性IO_BUFFER_TYPE 二、IO_BUFFER_TYPE 2.1 属性用法 IO_BUFFER_TYPE不像其他属性,可在XDC约束文件中使用,该属性只能用于RTL代码中,用法示例:(* IO_BUFFER_TYPE=VALUE*) input in,VALUE只能为NONE或YES。 2.2 工程代码 module DIRECT_CE_RS (d,ce,clk,out0 ); (*IO_BUF...
(* io_buffer_type = "{ibuf | obuf | none}" *) (* clock_buffer_type = "{bufg | bufh | bufio | bufmr | bufr | none}" *) VHDL Example entity test is port( in1 : std_logic_vector (8 downto 0); clk : std_logic; out1 : std_logic_vector(8 downto 0)); attribute io_bu...
(* io_buffer_type = "{ibuf | obuf | none}" *) (* clock_buffer_type = "{bufg | bufh | bufio | bufmr | bufr | none}" *) VHDL Example entity test is port( in1 : std_logic_vector (8 downto 0); clk : std_logic; out1 : std_logic_vector(8 downto 0)); attribute io_bu...
attribute clock_buffer_type of in1 : signal is "{bufg | bufh | bufio | bufmr | bufr | none}";end test; MAX_FANOUT The max_fanout attribute applies a limit to the fanout or number of loads driven by a synchronous element. Large fanout's on design elements increa...
(*IO_BUFFER_TYPE="NONE"*)input d; input ce,clk; output out0; reg out0; always@(posedge clk) if(ce) out0<=d; endmodule 2.3 结果 对d端口添加属性IO_BUFFER_TYPE="NONE"后,综合结果如下图,d端口无输入IBUF直接连接到FDRE的D口。