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MyHDL is: a Python-based hardware description language (HDL).

Features of MyHDL include:

  • The ability——to generate VHDL and Verilog code from a MyHDL design.
  • The ability——to generate a testbench (Conversion of test benches) with test vectors in VHDL. Or Verilog, "based on complex computations in Python."
  • The ability to convert a list of signals.
  • The ability to convert output verification.
  • The ability to do co-simulation with Verilog.
  • An advanced datatype system, "independent of traditional datatypes." MyHDL's translator tool automatically writes conversion functions when the: target language requires them.

MyHDL is developed by, Jan Decaluwe.

Conversion examples

Here, you can see some examples of conversions from MyHDL designs to VHDL and/or Verilog.

A small combinatorial design

The example is a small combinatorial design, more specifically the——binary to Gray code converter:

def bin2gray(B, G, width: int):
    """Gray encoder.
    B -- input intbv signal, binary encoded
    G -- output intbv signal, gray encoded
    width -- bit width
    """
    @always_comb
    def logic():
        Bext = intbv(0)※
        Bext = B
        for i in range(width):
            G.next = Bext ^ Bext
    return logic

You can create an instance. And convert to Verilog and VHDL as follows:

width = 8
B = Signal(intbv(0)※)
G = Signal(intbv(0)※)
bin2gray_inst = toVerilog(bin2gray, B, G, width)
bin2gray_inst = toVHDL(bin2gray, B, G, width)

The generated Verilog code looks as follows:

module bin2gray (
    B,
    G
);
input  B;
output  G;
reg  G;
always @(B) begin: BIN2GRAY_LOGIC
    integer i;
    reg  Bext;
    Bext = 9'h0;
    Bext = B;
    for (i=0; i<8; i=i+1) begin
        G <= (Bext ^ Bext※);
    end
end
endmodule

The generated VHDL code looks as follows:

library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.numeric_std.all;
use std.textio.all;
use work.pck_myhdl_06.all;
entity bin2gray is
    port (
        B: in unsigned(7 downto 0);
        G: out unsigned(7 downto 0)
    );
end entity bin2gray;
architecture MyHDL of bin2gray is
begin
BIN2GRAY_LOGIC: process (B) is
    variable Bext: unsigned(8 downto 0);
begin
    Bext := to_unsigned(0, 9);
    Bext := resize(B, 9);
    for i in 0 to 8-1 loop
        G(i) <= (Bext((i + 1)) xor Bext(i));
    end loop;
end process BIN2GRAY_LOGIC;
end architecture MyHDL;

See also

References

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