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New ContributorHow does Quartus Prime deal with arrays?
I am using VHDL to code a Deo nano SoC. This system has FPGA, CPU and ram. I am focused on the FPGA. I currently am reading data from an outside source and I load the data in a 300 element array. I then changed the array size to 3000 elements and recompiled. I copied the compilation report for both cases and I did not notice a difference in the resources. Where is the FPGA storing the array data and how much room do I have? I am self taught and it was my understanding that data was stored in a form of an IF THEN or similar statement.
4 Replies
sstrellSuper Contributor
It would help if you posted the code. Device resources get optimized away (or never synthesized at all) if it is determined they are not needed during compilation.
#iwork4intel
DKirvHere is an example of my code for a larger array.
Where are the elements in the array stored?
type t_Memory is array (0 to 1023) of std_logic_vector(31 downto 0);
signal my_array : t_Memory;
signal my_index : integer range 0 to 1023 := 0;
signal my_input : std_logic_vector(31 downto 0) ;
if flag = 3 then
my_index <= my_index + 1;
my_array(my_index) <= my_input;
end if;
if my_index = 1022 then
flag <= 4;
- DKirv
Yesterday, I was writing code and as I changed the parameters of an array, the RAM summary would change accordingly. Now the RAM appears to be utilized by the ALUs. Now I am out of ALU space. Is there a way to explicitly get QP to read/write array elements from RAM?
- DKirv
I found my problem. I had a runaway index.
