Kosyas41
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Hello,
I little bit confused with dual port RAM,my target is write and read data.I want to write data.like on the certain positions will be 128 and on the rest positions will be just 0.
I reading this article https://www.altera.co.jp/ja_JP/pdfs/literature/hb/qts/qts_qii51007.pdf
and I think I need true dual port Ram.
but the question.how can I write data to this Ram?
I little bit confused with dual port RAM,my target is write and read data.I want to write data.like on the certain positions will be 128 and on the rest positions will be just 0.
I reading this article https://www.altera.co.jp/ja_JP/pdfs/literature/hb/qts/qts_qii51007.pdf
and I think I need true dual port Ram.
Code:
library ieee;
use ieee.std_logic_1164.all;
entity true_dual_port_ram_single_clock is
generic (
DATA_WIDTH : natural := 8;
ADDR_WIDTH : natural := 6
);
port (
clk : in std_logic;
addr_a : in natural range 0 to 2**ADDR_WIDTH - 1;
addr_b : in natural range 0 to 2**ADDR_WIDTH - 1;
data_a : in std_logic_vector((DATA_WIDTH-1) downto 0);
data_b : in std_logic_vector((DATA_WIDTH-1) downto 0);
we_a : in std_logic := '1';
we_b : in std_logic := '1';
q_a : out std_logic_vector((DATA_WIDTH -1) downto 0);
q_b : out std_logic_vector((DATA_WIDTH -1) downto 0)
);
end true_dual_port_ram_single_clock;
architecture rtl of true_dual_port_ram_single_clock is
-- Build a 2-D array type for the RAM
subtype word_t is std_logic_vector((DATA_WIDTH-1) downto 0);
type memory_t is array((2**ADDR_WIDTH - 1) downto 0) of word_t;
-- Declare the RAM signal.
shared variable ram : memory_t;
begin
process(clk)
begin
if(rising_edge(clk)) then -- Port A
if(we_a = '1') then
ram(addr_a) <= data_a;
-- Read-during-write on the same port returns NEW data
q_a <= data_a;
else
-- Read-during-write on the mixed port returns OLD data
q_a <= ram(addr_a);
end if;
end if;
end process;
process(clk)
begin
if(rising_edge(clk)) then -- Port B
if(we_b = '1') then
ram(addr_b) := data_b;
-- Read-during-write on the same port returns NEW data
q_b <= data_b;
else
-- Read-during-write on the mixed port returns OLD data
q_b <= ram(addr_b);
end if;
end if;
end process;
end rtl;
