Cosim Namespace Reference

Helper class for software (C++) / firmware (VHDL) co-simulation. More...

Functions
std::string	display_value (const char *count, int size)
	Display value of the signal.
template<size_t N>
std::string	slv_to_bin_string (std::array< char, N > signal, bool padding=false)
	Transform into string.
template<size_t N>
void	display_hex (const std::array< char, N > &signal)
	Display signal in hex.
template<size_t N>
void	display_nonzero_hex (const std::array< char, N > &signal)
	Display nonzero value of signal in hex.
template<size_t nbits, size_t min, size_t max>
std::bitset< max - min+1 >	subset (std::bitset< nbits > set)
	extract a subset of bitstring, like substring. More...

Variables
const char *	std_logic_literal [] = {"U", "X", "0", "1", "Z", "W", "L", "H", "-"}
	In case you are not familiar with VHDL simulation, there are 9 possible values defined for the standard logic type, instead of just 0 and 1. More...
const char	one_val = 3
	'1' in XSI VHDL simulation
const char	zero_val = 2
	'0' in XSI VHDL simulation

Detailed Description

Helper class for software (C++) / firmware (VHDL) co-simulation.

Function Documentation

subset()

std::bitset< max - min + 1 > Cosim::subset

(

std::bitset< nbits >

set

)

extract a subset of bitstring, like substring.

In principle this can be done using only integer manipulations, but for the sake of simplicity, let's just cast them to string. Beware the endianness. 0 refer to the rightmost bit in std::bitset, but the leftmost bit in std::string

Definition at line 120 of file Cosim.h.

  {
    const size_t outWidth = max - min + 1;
    std::string str = set.to_string();
    return std::bitset<outWidth>(str.substr(nbits - max - 1, outWidth));
  }

Variable Documentation

std_logic_literal

const char* std_logic_literal[] = {"U", "X", "0", "1", "Z", "W", "L", "H", "-"}

In case you are not familiar with VHDL simulation, there are 9 possible values defined for the standard logic type, instead of just 0 and 1.

The simulator needs to compute all these possible outcomes. Therefore, XSI uses a byte, instead of a bit, to represent a std_logic. This is represented with a char with possible values ranging from 0 to 8.

Definition at line 40 of file Cosim.h.