MyHDL is a
Python
Python may refer to:
Snakes
* Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia
** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia
* Python (mythology), a mythical serpent
Computing
* Python (pro ...
-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)[width + 1 :]
Bext[:] = B
for i in range(width):
G.next[i] = Bext[i + 1] ^ Bext[i]
return logic
You can create an instance and convert to Verilog and VHDL as follows:
width = 8
B = Signal(intbv(0)[width:])
G = Signal(intbv(0)[width:])
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 [7:0] B;
output [7:0] G;
reg [7:0] G;
always @(B) begin: BIN2GRAY_LOGIC
integer i;
reg [9-1:0] Bext;
Bext = 9'h0;
Bext = B;
for (i=0; i<8; i=i+1) begin
G[i] <= (Bext[(i + 1)] ^ Bext[i]);
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
* Comparison of Free EDA software
* Comparison of EDA Software
* Electronic design automation (EDA)
* C to HDL compilers
References
{{Programmable Logic
Hardware description languages