Hi everyone;
I need to store data comes from an external ADC. So, i opted to use the
internal Memory M9K implemented in my Cyclone IV FPGA.
For that purpose, i used the mega-function ALTSYNCRAM provided by
Altera. The code is below:
1 | ENTITY RAM_2PORT IS
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2 | PORT
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3 | (
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4 | clock : IN STD_LOGIC := '1';
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5 | data : IN STD_LOGIC_VECTOR (31 DOWNTO 0);
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6 | rdaddress : IN STD_LOGIC_VECTOR (12 DOWNTO 0);
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7 | wraddress : IN STD_LOGIC_VECTOR (12 DOWNTO 0);
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8 | wren : IN STD_LOGIC := '0';
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9 | q : OUT STD_LOGIC_VECTOR (31 DOWNTO 0)
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10 | );
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11 | END RAM_2PORT;
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For this RAM there are two addresses, one fro write operations and the
other one for read operations. I have created init_file(ram.mif) with
known values, to initialize the RAM.
When i write a value in a specified address, i can read it after.
1 | if(rising_edge(CLOCK_50)) then
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2 |
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3 | if(interrupt_timer='1') then -- interrupt that activate the the write in the RAM
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4 | -- RAM dual port mode -----
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5 | RAM_W_address<='0' & X"001";
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6 | RAM_wren2<='1';
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7 | RAM_data_IN2<=X"55555557";
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8 |
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9 | else
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10 |
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11 | -- RAM dual port
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12 | RAM_wren2<='0';
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13 | RAM_R_address<='0' & X"001";
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14 | LED<=RAM_out2(15 downto 8);
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15 | end if;
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16 | end if;
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The problem is I get only zero when i want to read an initialized value
loaded from the init_file.
Do you have an idea what would be the problem ? Thank for any help.
Best Regards
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