calcaute_r.vhd

老师给我们的vhdl源代码

LIBRARY IEEE ;
USE  IEEE.STD_LOGIC_1164.ALL ;
LIBRARY WORK ;
USE  WORK.my_package.ALL ;

ENTITY  calculate_ohm  IS
PORT (  I_data  : IN  current ;
         U_data  : IN  voltage ;
         R_data  : OUT  resistance ) ;
END ENTITY calculate_ohm ;

ARCHITECTURE  behavioral  OF  calculate_ohm  IS
    SIGNAL I_tem:current:=10 uA;
    SIGNAL U_tem:voltage:=1 mV;
BEGIN
	calculate_ohms : PROCESS ( I_data, U_data )
	VARIABLE  temp_i, temp_v, temp_r :  INTEGER ; 
	BEGIN
		temp_v  :=  voltage'POS ( U_tem );  
		temp_i  :=  current'POS ( I_tem );  
		temp_r  :=  temp_v / temp_i ;  
		R_data  <=  resistance'VAL(temp_r); 
    END  PROCESS  calculate_ohms ;
END  behavioral ;