FPGAs 101

2.3. Mathematical Functions

Mathematical functions, such as adder, subtractor, multiplier, and divider, are performed using arithmetic operators; see Table 2-1. The arithmetic operators can be used in concurrent and/or sequential statements; it depends on the circuit. To keep things simple, this example uses only a concurrent statement, and a sequential statement is demonstrated in later examples.

Table 2-1. Mathematical functions

Symbol	Data Types	Package
Accepts	Returns
+Addition	std_logic, integer, std_logic_vector	std_logic_vector	std_logic_unsigned
signed, unsigned, natural, integer	signed, unsigned	numeric_std
–Subtraction	std_logic, integer, std_logic_vector,	std_logic_vector	std_logic_unsigned
signed, unsigned, natural, integer	signed, ...