696ded12 |
1 | -- J.STELZNER |
2 | -- INFORMATIK-3 LABOR |
3 | -- 23.08.2006 |
4 | -- File: PARITY_OUT.VHD |
5 | |
6 | library ieee; |
7 | use ieee.std_logic_1164.all; |
8 | |
9 | entity PARITY_OUT is |
10 | port( |
11 | PCI_CLOCK :in std_logic; |
12 | PCI_RSTn :in std_logic; |
13 | PAR_IN :in std_logic_vector ( 2 downto 0); |
14 | PAR_REG :in std_logic; |
15 | SERR_CHECK :in std_logic; |
16 | PERR_CHECK :in std_logic; |
17 | OE_PCI_PAR :in std_logic; |
18 | OE_PCI_PERR :in std_logic; |
19 | PA_ER_RE :in std_logic; |
20 | SERR_ENA :in std_logic; |
21 | PCI_PAR_IN :in std_logic; |
22 | PERR :out std_logic; |
23 | SERR :out std_logic; |
24 | PCI_PERRn :out std_logic; -- s/t/s |
25 | PCI_SERRn :out std_logic; -- o/d |
26 | PCI_PAR :out std_logic -- t/s |
27 | ); |
28 | end entity PARITY_OUT; |
29 | |
30 | architecture PARITY_OUT_DESIGN of PARITY_OUT is |
31 | |
32 | signal PAR :std_logic; |
33 | signal PAR_FF :std_logic; |
34 | signal SERR_FF :std_logic; |
35 | signal PERR_FF :std_logic; |
36 | |
37 | begin |
38 | |
39 | PAR <= ( PAR_IN(2) xor PAR_IN(1) xor PAR_IN(0) ); |
40 | |
41 | process (PCI_CLOCK, PCI_RSTn) |
42 | begin |
43 | if PCI_RSTn = '0' then PAR_FF <= '0'; |
44 | PERR_FF <= '0'; |
45 | SERR_FF <= '0'; |
46 | |
47 | elsif (PCI_CLOCK'event and PCI_CLOCK = '1') then |
48 | |
49 | PAR_FF <= PAR; |
50 | SERR_FF <= ((PCI_PAR_IN xor PAR) and SERR_CHECK) and PA_ER_RE and SERR_ENA and (not SERR_FF); |
51 | PERR_FF <= ((PCI_PAR_IN xor PAR) and PERR_CHECK) and (not PERR_FF); |
52 | |
53 | end if; |
54 | end process; |
55 | |
56 | SERR <= SERR_FF; |
57 | PERR <= PERR_FF; |
58 | |
59 | PCI_PAR <= PAR_FF when OE_PCI_PAR = '1' else 'Z' ; |
60 | PCI_SERRn <= '0' when SERR_FF = '1' else 'Z' ; |
61 | PCI_PERRn <= not PERR_FF when OE_PCI_PERR = '1' and PA_ER_RE = '1' else 'Z' ; |
62 | |
63 | end architecture PARITY_OUT_DESIGN; |
64 | |
65 | |
66 | |