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各位大大好~
: G2 n% P4 j/ M我要用ADC0804抓一個0~5V 電壓~
9 P- }' @/ m6 I, [, r- f9 J* n' R下面是唐佩忠那本書裡面的ADC0804的VHDL程式碼~, L- y0 r5 W* y* o' u
他只有對0804的WR跟RD做控制~~
$ I3 E6 e F& j$ v6 G# d0 D那CS 跟INTR都不用做控制嗎?
7 K' r, v t: k
- H0 O0 ^, F. I& g不知道有沒有大大~有用過FPGA來控過ADC0804的嗎?7 R" a0 u4 g& d0 }0 Z1 O# r
希望可以向你請叫問題~
7 E! Y9 [8 @: y& c4 P- Q" D6 u, i1 T9 ]非常感謝~~
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Library IEEE;
% h7 a9 [' ^# N2 g A6 l, l( k$ j; I. sUSE IEEE.std_logic_1164.ALL;
) H' [. T! R" m! D* U! xUSE IEEE.std_logic_arith.ALL;
1 U, p+ \; u7 I8 C/ k3 A7 s k- IUSE IEEE.std_logic_unsigned.ALL;! r- e+ y) C' u7 t% ~
ENTITY ADC0804 IS
. p6 t! s& l8 m PORT
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AOP : OUT STD_LOGIC_VECTOR(7 DOWNTO 0);
& S* ]1 a7 n1 ~( | AIN : IN STD_LOGIC_VECTOR(7 DOWNTO 0);+ u% T' P# w5 _1 \ X. x& ?2 S) D
WR : OUT STD_LOGIC;1 y) q, v4 w, p1 Z
RD : OUT STD_LOGIC;
1 D0 z0 g# E' E9 c: J4 u CLK : IN STD_LOGIC;
- D v* {( d& Q+ O- z0 d& I% ~ FERQ : IN STD_LOGIC
9 M$ e8 h0 S1 ]. m- ~ );
4 A: e7 B7 v! ]3 D7 N# @END ADC0804;
/ D9 q. `3 s5 e V) ?, LARCHITECTURE a OF ADC0804 IS
* d8 G( s( k# N$ G6 n. }SIGNAL D0,D1,D2,D3 : STD_LOGIC;
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--*********************************************************************- v7 p8 _. s3 @# t" e
time_sequence : block
5 g: X# P. z7 P8 fBEGIN: r! c5 N1 Z- P- P) G5 C2 j
process(CLK)
- H2 G+ P8 K0 ^ begin
; W$ ^$ p. y1 h if CLK'event and CLK='1' then7 K( m. J2 u( D1 D2 Y
D3<=D2;
9 C- p2 V* K4 s4 t: f" l D2<=D1;. O8 U. J. ` X1 D( S3 |
D1<=D0;
# T$ u% E; I0 j1 d& h+ m D0<=FERQ; y2 K1 T$ k. h2 E5 ^3 j" I! S
END if;
. X* r6 C! @7 L# t- P6 n end process;4 K2 R+ _$ Y$ H' e! j/ b4 @
RD <= not (FERQ or D0 or D1);
: h& j9 z- Q+ M+ |7 [7 f$ Z WR <= not D3;
" _& Y: Q2 W+ v, m( @6 W/ B. Qend block time_sequence;7 m; r0 m- g) T
--*********************************************************************
4 j% E, w6 w) l4 EADC_FETCH : block
. S: ^4 Z' O+ {# M SIGNAL EC : STD_LOGIC;, E; v7 M! ]" A6 Y P
begin
9 _7 R L4 j; s process(CLK)
$ | t/ ]/ p0 i* a& B, k begin
# H3 x3 s9 z- X if CLK'event and CLK='1' then1 ?8 l0 N" P% X
if EC='1' then
6 p2 _( J' n# |+ d' I4 _5 [ AOP <= AIN;
" m9 q" \: r+ G3 W2 P end if;3 a: f& Q: E$ n: d
end if;
- m1 _6 c) P, I) ~ end process;1 b V6 M& M, P' q2 K% T! b. @
EC <= D1;8 B) D0 F7 P2 h# t; x/ ?! w$ ?+ E
end block ADC_FETCH;- h. \/ T& }# C/ h4 l# Q
END a; |
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