錯誤訊息

canoe1114

使用軟體:MAX+plus 2
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4 @) ~' S3 w" l, n錯誤訊息:warning Line 101:File c:\documents and setting\adminstrator\桌面\anew.vhd:
) @5 T, O9 u$ f- s! t# ?% RFuond multiple assignmengs to the same singal or signal bit"cutting0"in a Process Statement-
only the lase assignment will take effect
4 b  Z' T- I8 L- W, }& x, g程式說明:
1 x4 V) t7 N- M1 H! Zentity anew is
) K4 l/ d: F) |# a8 I        port (
                clock:in std_logic;
9 D6 j5 J% l/ G8 z- R! Z                enable:in std_logic;
                direction:in std_logic;
                selection:in std_logic_vector(1 downto 0);
                cutting:out std_logic_vector(3 downto 0);
4 o. e% g' k% I3 T& l                phase:out std_logic_vector(3 downto 0));
/ N) W0 B7 P4 d. H' m4 {. M1 [! Iend anew;
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2 X4 x' I7 s) Yarchitecture wena of anew is
% P  t/ f; g/ a- I* o% vbegin
) ~' K9 U, D/ c4 q5 j        process(clock,enable,direction,selection)
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        variable countcut2:integer range 0 to 3;
1 A4 m3 o6 H' M- h        variable countcut3:integer range 0 to 7;
        variable countcut4:integer range 0 to 15;
        variable countphase:integer range 0 to 7;
        cutting
宣告的四個variable均是對同一個輸出而設定
如果 variable countcut1:integer range 0 to 3;則輸出到cutting(1 downto 0)
如果 variable countcut2:integer range 0 to 3;則輸出到cutting(2 downto 0)
/ O6 J: N) v. c& h* q& ?如果 variable countcut3:integer range 0 to 3;則輸出到cutting(3 downto 0)
以上的指定是用 : case  is  when ...
" g6 ~8 ~: U* `" m) h* [) \但四種狀態是個別發生

4 @6 t: f1 i- ~6 H出現的訊息說不能重覆設定不然只以最後一個設定為準

( ^% p" A7 k2 R  _7 ]" X, x5 A- p請問有什麼方法可以解決此問題嗎
" A9 U7 ^- ?2 k; V因為不想設定這麼多支接角(epm7032)
也有試過將cutting:out std_logic_vector(3 downto 0);
再分成用alias的子集合..但也不行
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