Array and Records in VHDL Digital Design using VHDL by Ravinder Nath Rajotiya - May 13, 2021May 13, 20210 Composite Data Type: In addition to predefined type, VHDL also allow us to use array and record types in our VHDL designs. This can provide us with a more structured design which is easier to maintain. These are of two types: Array Record: records are like structures in C language. They allow us to use different types Array: An array is a collection / group of elements of the same type as a single object. Array can be of any type In VHDL. Array can be one dimension, two dimension and multi dimension. Syntax: type <type_name> is array (<range> ) of <type> ; the <range> field in the above example can be built using the downto and to VHDL keywords Type of Arrays Constrained type array Unconstrained
Data Types in VHDL Digital Design using VHDL by Ravinder Nath Rajotiya - May 10, 20210 Data Types in VHDL The syntax of object declaration as studied in the previous chapter is again revisited. Object_class Object_name : Object_data_type[:= Initial_value]; The essential component of the above declaration is object class and data type. Whereas the class signifies the class/category (signal, variable, constant, file) to which the object belongs, the data type gives an idea of the type (bit, Boolean, std_logic, integer etc.) -of the values an object may take and the value from a set of the values that an object may be assigned. Every given data type supports some specific operations for the object for example data type bit supports logical and arithmetic operations but std_logic (as given in std-logic_1164) does not support arithmetic operation. If arithmetic operation on std_logic