EMIF (External Memory Interface) 是 Quartus 平台提供的 IP，用于实现高速存储器件接口与控制器。通过 Intel Quartus Prime 软件，可以很方便地实现 EMIF IP 电路。本文记录了使用 EMIF 实现 DDR3 控制器的仿真过程，软件平台为 Quartus Prime Pro 21.3，器件型号为 10CX220YF780E6G.

1 EMIF IP 介绍

2 EMIF DDR3 IP 配置

3 EMIF DDR3 IP 仿真

1 EMIF IP 介绍

Intel EMIF IP 是 Quartus 平台提供的 IP，用于实现高速存储器件接口与存储控制器电路。借助 EMIF 电路，FPGA 可以与外部存储器件进行数据交换。

EMIF IP 实现物理层接口与存储控制器，这两部分的功能说明如下：

物理层接口（Physical Layer Interface），用于建立数据通路，以及管理 FPGA 和存储器件的传输时序；
存储控制器（Memory Controller），实现内存命令与协议层规范。

EMIF IP 的总体设计流程如下图：

EMIF IP 设计过程中涉及许多参数与配置步骤，IP 配置完成之后，可以生成参考工程，用于功能仿真，以检查参数配置是否有误。

2 EMIF DDR3 IP 配置

新建工程，器件型号选择 10CX220YF780E6G。

在 IP Catalog 中输入 memory，然后双击选择 External Memory Interfaces Intel Cyclone 10 FPGA IP。

Memory Protocol 选 DDR3，时钟频率和 PLL 参考时钟频率根据需要配置，这里时钟频率填 933M，PLL 参考时钟频率为 116.625MHz.

（PS：右下角 Presets 中有预设的选项，双击可以直接应用）

容量为 1Gb 的 DDR3，行地址为 13bit，DQ width 根据实际器件类型填写。

中间时序参数可以先跳过，最后有个仿真选项，选择 Skip Calibration，跳过校准阶段。

IP 配置完成之后，点击 Generate Example Design，生成参考工程。

3 EMIF DDR3 IP 仿真

在前面生成的参考工程中，仿真相关文件在 sim/ed_sim/mentor 和 sim/ed_sim/sim 路径下。修改 sim/ed_sim/sim 路径下的 ed_sim.v 文件，替换掉 ed_sim_tg 模块例化代码，就可以仿真自己编写的控制逻辑。

仿照 ed_sim_tg 模块接口，编写 ed_sim_tg_0 模块，代码如下：

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;entity ed_sim_tg_0 isgeneric(AMM_WRITE_PATTERN   : std_logic_vector := X"0102030405060708090A0B0C0D0E0F10";AMM_WRITE_INC       : std_logic_vector := X"01010101010101010101010101010101");port(emif_usr_reset_n    : in std_logic;emif_usr_clk        : in std_logic; -- 233MHzlocal_cal_success   : in std_logic;amm_ready_0         : in std_logic;amm_read_0          : out std_logic;amm_write_0         : out std_logic;amm_address_0       : out std_logic_vector(28 downto 0);amm_readdata_0      : in std_logic_vector(127 downto 0);amm_writedata_0     : out std_logic_vector(127 downto 0);amm_burstcount_0    : out std_logic_vector(6 downto 0);amm_byteenable_0    : out std_logic_vector(15 downto 0);amm_readdatavalid_0 : in std_logic);
end entity;
architecture behav of ed_sim_tg_0 is
-- internal signal declarations
type state is (st_emif_init,st_amm_idle,st_amm_write,st_amm_read
);
signal pstate                  : state := st_emif_init;
signal buf_amm_read_0          : std_logic;
signal buf_amm_write_0         : std_logic;
signal cnt_amm_write_0         : std_logic_vector(7 downto 0);
signal buf_amm_address_0       : std_logic_vector(28 downto 0);
signal buf_amm_writedata_0     : std_logic_vector(127 downto 0);
signal buf_amm_burstcount_0    : std_logic_vector(6 downto 0);
signal buf_amm_byteenable_0    : std_logic_vector(15 downto 0);
signal cnt_amm_readdatavalid_0 : std_logic_vector(7 downto 0);
------------------------------------------------------
begin
------------------------------------------------------
amm_write_0      <= buf_amm_write_0;
amm_read_0       <= buf_amm_read_0;
amm_address_0    <= buf_amm_address_0;
amm_writedata_0  <= buf_amm_writedata_0;
amm_burstcount_0 <= buf_amm_burstcount_0;
amm_byteenable_0 <= buf_amm_byteenable_0;process(emif_usr_reset_n,emif_usr_clk) 
beginif emif_usr_reset_n = '0' thenpstate <= st_emif_init;buf_amm_write_0 <= '0';cnt_amm_write_0 <= (others => '0');buf_amm_read_0 <= '0';buf_amm_address_0 <= (others => '0');buf_amm_writedata_0 <= (others => '0');buf_amm_burstcount_0 <= (others => '0');buf_amm_byteenable_0 <= (others => '0');cnt_amm_readdatavalid_0 <= (others => '0');elsif rising_edge(emif_usr_clk) thencase(pstate) iswhen st_emif_init => if local_cal_success = '1' thenpstate <= st_amm_idle;elsepstate <= st_emif_init;end if;when st_amm_idle => pstate <= st_amm_write;buf_amm_writedata_0 <= AMM_WRITE_PATTERN;buf_amm_address_0 <= buf_amm_address_0 + 1;when st_amm_write => if cnt_amm_write_0 = 63 thencnt_amm_write_0 <= (others => '0');buf_amm_write_0 <= '0';buf_amm_byteenable_0 <= (others => '0');pstate <= st_amm_read;buf_amm_read_0 <= '1';elseif buf_amm_write_0 = '1' and amm_ready_0 = '1' thencnt_amm_write_0 <= cnt_amm_write_0 + 1;buf_amm_writedata_0 <= buf_amm_writedata_0 + AMM_WRITE_INC;end if;buf_amm_write_0 <= '1';buf_amm_burstcount_0 <= conv_std_logic_vector(64,7);buf_amm_byteenable_0 <= (others => '1');pstate <= st_amm_write;end if;when st_amm_read => if buf_amm_read_0 = '1' and amm_ready_0 = '1' thenbuf_amm_read_0 <= '0';end if;if cnt_amm_readdatavalid_0 = 64 thencnt_amm_readdatavalid_0 <= (others => '0');pstate <= st_amm_idle;elseif amm_readdatavalid_0 = '1' thencnt_amm_readdatavalid_0 <= cnt_amm_readdatavalid_0 + 1;end if;pstate <= st_amm_read;end if;when others => NULL;end case;end if;
end process;
end architecture;

打开 Modelsim 读取 msim_setup.tcl 文件，编译 EMIF IP 文件与用户设计文件，并启动仿真。