How to find largest value and its position in memory array?

to get max of stream:

in a clocked process:

if din > max then

max <= din;

addr_of_max <= addr;

end if;

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to get max of stream:

in a clocked process:

if din > max then

max <= din;

addr_of_max <= addr;

end if;

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Hi Kaz, thanks for your reply... i know the concept... but I have no idea how to write it in Verilog code... though I have tried for several times, the output is wrong...

I have written the code in vhdl, which should work provided you look after type issues(signed...etc).

You can write verilog on same basis.

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I have written the code in vhdl, which should work provided you look after type issues(signed...etc).

You can write verilog on same basis.

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Hi Kaz, here is my code... but it's wrong... can you figure out my mistake?

module absolute(clock,Enable, d_in, max_value) ;

input wire clock;

input wire Enable;

input wire [9:0] d_in;

output reg [9:0] max_value;

reg [9:0] max_val_tmp;

reg [2:0] Q;

reg [9:0] mem_array [0:7];

initial

begin

max_val_tmp = mem_array[0];

end

always @ (posedge clock)

begin

if (Enable)

begin

mem_array[Q] <= d_in;

if (mem_array[Q] > max_val_tmp)

begin

max_value <= mem_array[Q];

end

else

begin

max_value <= max_val_tmp;

end

Q <= Q + 1;

end

end

endmodule

I suggested:

always @ (posedge clock)
       begin 
             if (Enable) 
                   begin
                        if (din > max_val)
                           begin
                              max_val <= din;
                              Q_val <= Q;
                           end
                          Q <= Q + 1;
       end 
end

you need to take care of verilog syntax and rules as I am not good at it. You also need to take care of address latency.

I also thought you are reading from memory but your code suggest are just writing to an array from din?? so which is'it? Anyway the code for din above should work in principle. what you do with din before/after is your focus.

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I suggested:

always @ (posedge clock)
       begin 
             if (Enable) 
                   begin
                        if (din > max_val)
                           begin
                              max_val <= din;
                              Q_val <= Q;
                           end
                          Q <= Q + 1;
       end 
end

you need to take care of verilog syntax and rules as I am not good at it. You also need to take care of address latency.

I also thought you are reading from memory but your code suggest are just writing to an array from din?? so which is'it? Anyway the code for din above should work in principle. what you do with din before/after is your focus.

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Thank you Kaz for your time :)

I have tried the codes below, both with mem_array and without mem_array gave the same results which are wrong... (as picture attachment)

module absolute(clock,Enable, d_in, max_value, max_location) ;

input wire clock;

input wire Enable;

input wire [9:0] d_in;

output reg [9:0] max_value;

output reg [2:0] max_location;

reg [9:0] max_val_tmp;

reg [2:0] Q;

//reg [9:0] mem_array [0:7];

initial

begin

max_val_tmp = 0;

end

always @ (posedge clock)

begin

if (Enable)

begin

//mem_array[Q] <= d_in;

if (d_in > max_val_tmp)

begin

max_value <= d_in;

max_location <= Q;

end

Q <= Q + 1;

end

end

endmodule

**p.s. I need to write d_in into mem_array[Q] so that i can keep track on its location right?

**another way i found something:

"develop a verilog model for a peak detector that finds the maximum value in a sequence of 10-bit unsigned integers. a new number arrives at the input during a clock cycle when the data_en input is 1. if the new number is greater than the previously stored maximum value, the maximum value is updated with the new number; otherwise, it is unchanged. the stored maximum value is cleared to zero when the reset control input is 1. both data_en and reset are synchronous control inputs."

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Thank you Kaz for your time :)

**p.s. I need to write d_in into mem_array[Q] so that i can keep track on its location right?

**another way i found something:

"develop a verilog model for a peak detector that finds the maximum value in a sequence of 10-bit unsigned integers. a new number arrives at the input during a clock cycle when the data_en input is 1. if the new number is greater than the previously stored maximum value, the maximum value is updated with the new number; otherwise, it is unchanged. the stored maximum value is cleared to zero when the reset control input is 1. both data_en and reset are synchronous control inputs."

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What another way? It is same one I am telling you since last year!!

and your code : why do you keep using the wrong signal name: why do you use max_val_tmp, I did not say that.

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What another way? It is same one I am telling you since last year!!

and your code : why do you keep using the wrong signal name: why do you use max_val_tmp, I did not say that.

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last year?? i just joined today... if i didn't create a temparory reg "max_val_tmp" how can keep the number for comparing with the next number??

if you don't mind to edit my whole codes, so i don't make any mistakes again won't ask you anymore??

now i change to these codes and the output as shown in picture attachment...

input wire Enable;

input wire [9:0] d_in;

output reg [9:0] max_value;

output reg [2:0] max_location;

reg [2:0] Q;

initial

begin

max_value = 0;

end

always @ (posedge clock)

begin

if (Enable)

begin

if (d_in > max_value)

begin

max_value <= d_in;

max_location <= Q;

end

Q <= Q + 1;

end

end

endmodule

Just use my above code. The max_val updates and stores din by itself until it is updated (if at all).

I am sorry I have not done verilog for years so can't help directly at code level.

Yourlast code and waveforms looks ok to me