4

我正在尝试用 VHDL 语言制作一个 ROM，我正在使用在http://www.edaboard.com/thread38052.html上找到的这个模板：

library ieee;
use ieee.std_logic_1164.all;

entity ROM is
port ( address : in std_logic_vector(3 downto 0);
     data : out std_logic_vector(7 downto 0) );
end entity ROM;

architecture behavioral of ROM is
type mem is array ( 0 to 2**4 - 1) of std_logic_vector(7 downto 0);
constant my_Rom : mem := (
0  => "00000000",
1  => "00000001",
2  => "00000010",
3  => "00000011",
4  => "00000100",
5  => "11110000",
6  => "11110000",
7  => "11110000",
8  => "11110000",
9  => "11110000",
10 => "11110000",
11 => "11110000",
12 => "11110000",
13 => "11110000",
14 => "11110000",
15 => "11110000");
begin
process (address)
begin
 case address is
   when "0000" => data <= my_rom(0);
   when "0001" => data <= my_rom(1);
   when "0010" => data <= my_rom(2);
   when "0011" => data <= my_rom(3);
   when "0100" => data <= my_rom(4);
   when "0101" => data <= my_rom(5);
   when "0110" => data <= my_rom(6);
   when "0111" => data <= my_rom(7);
   when "1000" => data <= my_rom(8);
   when "1001" => data <= my_rom(9);
   when "1010" => data <= my_rom(10);
   when "1011" => data <= my_rom(11);
   when "1100" => data <= my_rom(12);
   when "1101" => data <= my_rom(13);
   when "1110" => data <= my_rom(14);
   when "1111" => data <= my_rom(15);
   when others => data <= "00000000";
 end case;
  end process;
  end architecture behavioral;

好吧，问题是我想输入我的 ROM 2000 值。所以我想知道如何使用python制作下一个：

想象一下，您在 .txt 文件中有以下格式的数据：

0  45
1  56
2  78
3  98

所以程序会对数据执行此操作：

0 => "00101101"
1 => "00111000"
2 => "01001110"
3 => "01100010"

那么这些值 "00101101","00111000","01001110","01100010" 是 45,56,78 y 89 的二进制表示的各自值。所以，你明白了......

有一个小细节，需要指定表示的位数：如果你不这样做，你可以得到这个：

0 => "101101"
1 => "111000"
2 => "1001110"
3 => "1100010"

非常感谢所有可能的代码片段来完成这个程序

4

4 回答 4

5

这是另一种方法；在 MyHDL 中使用 toVHDL 转换器。您可以使用任意 Python 表达式来初始化元组。

这是 MyHDL 描述：

from myhdl import *

def VhdlRomGen(addr, data):

    # Create the ROM container
    rom = [Signal(intbv(0)[8:]) for ii in range(2**4)]

    # Initialize ROM, any value, any complex python can
    # be in this initialization code.
    for ii in xrange(len(rom)):
        rom[ii] = ii

    rom = tuple(rom)

    @always_comb
    def rtl_rom():
        data.next = rom[int(addr)]


    return rtl_rom

if __name__ == "__main__":
    addr = Signal(intbv(0)[4:])
    data = Signal(intbv(0)[8:])

    toVHDL(VhdlRomGen, addr, data)

这是转换后的 VHDL：

-- Generated by MyHDL 0.7
-- Date: Sat May 21 15:39:27 2011


library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.numeric_std.all;
use std.textio.all;

use work.pck_myhdl_07.all;

entity VhdlRomGen is
        port (
            addr: in unsigned(3 downto 0);
            data: out unsigned(7 downto 0)
        );
end entity VhdlRomGen;


architecture MyHDL of VhdlRomGen is
begin

VHDLROMGEN_RTL_ROM: process (addr) is
begin
    case to_integer(addr) is
        when 0 => data <= "00000000";
        when 1 => data <= "00000001";
        when 2 => data <= "00000010";
        when 3 => data <= "00000011";
        when 4 => data <= "00000100";
        when 5 => data <= "00000101";
        when 6 => data <= "00000110";
        when 7 => data <= "00000111";
        when 8 => data <= "00001000";
        when 9 => data <= "00001001";
        when 10 => data <= "00001010";
        when 11 => data <= "00001011";
        when 12 => data <= "00001100";
        when 13 => data <= "00001101";
        when 14 => data <= "00001110";
        when others => data <= "00001111";
    end case;
end process VHDLROMGEN_RTL_ROM;
end architecture MyHDL;
于 2011-05-21T20:49:43.350 回答
5

作为其他答案的替代方案，请将您的 ROM 存储为naturals 或integers （视情况而定）。那么你的常数可以是以下形式：

0 => 45,
1 => 56, ...

等等

如果您已经拥有所有值，则可以将它们全部放在一个大的逗号分隔符系列中，而无需进行n =>位置映射。

(45, 56, 78, 98,....)

此外，如果您将地址输入为数字类型（unsigned或者natural根据您的喜好），您可以将地址解码简化为

data <= my_rom(address);

或者

data <= my_rom(to_integer(address));
于 2011-02-11T15:44:56.003 回答
4 
for line in open('your_file.txt'):
    s = line.strip().split("  ") # two spaces are for split
    p = '{} => "{:0{min_bits}b}"'.format(s[0], int(s[1]), min_bits=10)
    print p
于 2011-02-11T09:10:45.067 回答
2

尝试这个：

bit_count = 8
format_template = '{{0}} => "{{1:0{0}b}}"'.format(bit_count)
with open(r"input_file.txt") as input_file:
    for line in input_file:
        data = map(int, line.split())
        print format_template.format(*data)
于 2011-02-11T09:15:27.853 回答