don't rewrite .xco all the time

[raggedstone] / dhwk / source / IO_RW_SEL.vhd

-- J.STELZNER\r
-- INFORMATIK-3 LABOR\r
-- 23.08.2006\r
-- File: CONFIG_WR_SEL.VHD\r
\r
library IEEE;\r
use IEEE.std_logic_1164.all;\r
\r
entity IO_WR_SEL is\r
	port\r
	(\r
	IO_WR_COM		:in		std_logic;\r
	IRDY_REGn		:in		std_logic;\r
	TRDYn				:in		std_logic;\r
	ADDR_REG		:in		std_logic_vector(31 downto 0);\r
	CBE_REGn		:in		std_logic_vector( 3 downto 0);\r
	WRITE_XX1_0	:out	std_logic;\r
	WRITE_XX3_2	:out	std_logic;\r
	WRITE_XX5_4	:out	std_logic;\r
	WRITE_XX7_6	:out	std_logic \r
	);\r
end entity IO_WR_SEL;\r
\r
--PCI Byte Enable \r
--C/BE[3..0] gueltige Datenbits \r
-------------------------------\r
--	0000		AD 31..0\r
--	1000		AD 23..0\r
--	1100		AD 15..0\r
--	1110		AD  7..0\r
--	0011		AD 31..16\r
\r
architecture IO_WR_SEL_DESIGN of IO_WR_SEL is\r
\r
	signal	WR_ENA	:std_logic;\r
	signal	ADDR		:std_logic_vector( 5 downto 0);	\r
\r
begin\r
\r
		WR_ENA	<=	'1' when\r
										IO_WR_COM = '1'	and\r
										IRDY_REGn	=	'0' and\r
							 			TRDYn			=	'0'	else	'0';\r
\r
\r
		ADDR	<=	 ADDR_REG(3) &	ADDR_REG(2)	&	CBE_REGn;\r
\r
\r
		WRITE_XX1_0	<=	'1'	when	WR_ENA	=	'1'	and	ADDR	=	"001100"	else '0';	 \r
		WRITE_XX3_2	<=	'1'	when	WR_ENA	=	'1'	and	ADDR	=	"000011"	else '0';\r
		WRITE_XX5_4	<=	'1'	when	WR_ENA	=	'1'	and	ADDR	=	"011100"	else '0';	 \r
		WRITE_XX7_6	<=	'1'	when	WR_ENA	=	'1'	and	ADDR	=	"010011"	else '0';\r
	\r
end architecture IO_WR_SEL_DESIGN;\r