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Vhdl Full Adder

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48 Threads found on Vhdl Full Adder
if you use a programmable logic and you use vhdl or verilog you must define a vector of 9 bits. when you add you 3 8 bits you have the carry gratis. bye. G.
Here's vhdl code for a full adder and Half adder: - Jayson
I am having a Halfadder Module... I want to make a full adder by using the Halfadder module... How to implemnt it in vhdl?....
Hi Werner ;-) for a vhdl solution s. Similar Threads below. For schematics use G00GLE, s. this thread.
you can use the common "+" statement to indicate it is a plus operation, and use according synopsys directive statement in your vhdl comment, then DC will call the DesignWare library cell to do it
Dear, I need a help in writing a vhdl cobe for a 4bit full-adder regards
Hii I am having a problem with a test bench in vhdl the following is my code for a full adder:: library IEEE; use IEEE.STD_LOGIC_1164.ALL; use ieee.numeric_std.all; entity adderwa is generic (n:positive:=4); port(a,b:in std_logic_vector(n-1 downto 0); cin:in std_logic; sum:out std_logic_vector(n-1 downto (...)
i have just learned to write on vhdl and I have completed my first full adder code using components for the xor, and, or gates but im not sure if its right, could someone please tell me if this is right? I do not have vhdl ive written this on notepad.. -- For XOR gates: library IEEE; use IEEE.std_logic_1164.all; (...)
Hi can anybody give the idea for desining a 1-bit full adder of behavioral modeelling using case/if ststements
Hello every one i need your help in vhdl . actually i need a code to design a full adder using a Decoder .. and thank you for such great forum ...
Dear, I need a help in writing a vhdl cobe for a 2bit full-adder using 2 half adder regards
Just write vhdl code based on truth table.
first design four bit adder from one bit adder .then you can design 16bit adder from 4 full adder circuit.the code is available for this module in Xilinx website. Hi Preetam, Thanks a lot for your reply! The 4 bit adder is a pure combinational circuit. It seems that the (...)
Hi, I have to develop a program on leakage current estimation and reduction in a full adder circuit using vhdl. Please Reply ASAP. Thanks.
in vhdl sum <= a xor b xor carry_in; -- each is 1 bit carry_out <= (a AND b) OR (a AND carry_in) OR (b AND carry_in); -- either 2 of the input is 1 then there is a carry out we need bout 7 basic logic gates... how many gates required to build the decoder? is it cost effective? i wonder is it better way to use decoder as multiplier so no
use your loaf use google
Hello friends.. can you tell me something about designing a up down counter using only half adders (and flip flops) say for 4 bit ? vhdl code would also do ...or a logic diagram or a link....? thanks....
any code available ?? on vhdl and also tutorial points will be given....... ty in advance
could you give some details about this adder because we need it for vhdl design.... thnx....
Refer book to understand design and test bench writing : Hdl Chip Design: A Practical Guide for Designing, Synthesizing & Simulating Asics & Fpgas Using vhdl or Verilog by Douglas J. Smith Also below link is useful
4x4 multiplier can be implemented with a scaling accumulator multiplier which performs multiplication using an iterative shift-add operations. EDIT: check this pdf which contains 4x4 multiplier
You can download the Xilinx Webpack for free here: Xilinx: Downloads A fulladder vhdl code looks like this: -- This is just to make a reference to some common things needed. LIBRARY IEEE; use IEEE.STD_LOGIC_1164.ALL; -- We declare the 1-bit adder with the inputs and outputs -- shown in
Nightlamp, I would assume that c_in is your carrier bit?....If so the beauty of vhdl is that vhdl takes care of the carrier bit for you. Are you trying to add from 000 to 111? If so you can use integer range instead of std_logic when you declare your variables. something like this PORT( A:IN INTEGER RANGE 0 to 7
this may help u vhdl Tutorial
Hi to all, i'm studying the vhdl language, and i'm trying to do some exercise! i did a simple full adder, it works, i have already test it, and with the same criteria i did a ripple carry adder at 8 bits,but i have a problem with the simulation, the error is: # Loading work.rcatb(tb) # ** Warning: (vsim-3473) Component (...)
Hi, I try to read but it seem like I can't understand it clearly. Can roughly what does each lines does? Of course I can, but you won't be any wiser compare the schematics of the full adder on wikipedia with what has been coded. Maybe you'll find some similarities. As such you will probably understand it. 2nd
I didn't see that P is an output in your top level design. You need to declare a signal that can be used internally that you would then set P equal to. You cannot read an output signal. It seems like this is the first time you worked with structural vhdl design. I suggest you read:
Hi You are welcome to see some free projects and vhdl tips at: vhdl, verilog, design, verification, scripts, ... " Record array in vhdl using free simulator GHDL. record tip A simple guide describing how to print from vhdl code. print tip The importance of stop on fata
Old vhdl versions had the problem that a port of the buffer type must be continued as buffer through the hierarchy. The restriction doesn't apply to recent vhdl. But the suggestion to copy the signal is reasonable for clarity, though.
There arnt any. You have to build your own or get someone elses. vhdl does not containt libraries of specific constructs, just abstracted ideas as different tools and vendors may do things differently.
is there anythin specific.. actually there are lotsa things u can implement. wot did u get with the xilinx's developer's kit.. did u get a general purpose kit? if u had purchased a general purpose kit u can try some programs like half, full adder and subtractor, u can also try the MUX and Demux programs.. which version of xilinx webpack did u ge
hi, i got the same problem too. i want to create 4-to1-package mux to built 16-to-1 mux. i've read some tutorial from quartus but could not find the answer. but i've read from google groups that previous version of quartus did not support the vhdl package. but i'm not sure about the latest version. anyone know how to solve the probs?
I am generating post P&R vhdl file from Leonardo. While compiling it in modelsim error is coming like no default binding for 'ibuf' and 'obuf'. If I generate same file from the Xilinx then it includes simprim and unisim file. But file generated from Leonardo don't include any such file. Pls help me Program is of simple full adder. (...)
As Iouri suggested, the '-' operator in HDL (such as Verilog or vhdl) is easy to use, and usually generates well-optimized logic for your target device. The results will probably be as small and fast as anything you create yourself. What is "FA"?
A delay for output sum might solve. For vhdl ex: sum <= ( a xor b ) afte 5 ns ; carry <= ( a and b ) after 5 ns ;
Hi everyone, I am wondering if it is possible to write a vhdl/verilog code and uses it to generate the schematic and layout so that I can combine it with my own full custom design? For instance, say I am working on a adder. In order to test the adder, I need to layout not only the adder, but the (...)
can anyone help the following assignment? A ripple-carry adder is designed using for-loop construction. The simplest way to describe a ripple-carry adder is to use a chain of 1-bit full-adders (see figure below where 4-bit ripple carry adder is implemented using 1-bit full (...)
hii everyone, I'm new in vhdl and I'm trying to design a modulo generic adder by using ROM. The output for the adder should be (x + y)mod m. I have no idea on how to create it.
Here c_out is a signal and carry is a variable. In vhdl, a signal will be updated with a small delay. So dependent assignments like above will not happen in the same clock cycle. But variable will be updated immediately. For the first clock cycle: c_out(0) <='1'; carry(0) := old value of c_out(0) = '1'; c_out(1) <= '1' xor '1' = '0'; --old va
Hi all, I am using TetraMAX to generate test patterns for a full adder code. The problem is at the stage "Write Patterns", Synopsys no longer let us the patterns in Verilog or vhdl, you will receive the error "write_patterns -format verilog_single_file is obsolete; command ignored". I can only save as STIL, binary....But I want to have a (...)
hello i need help for my code in test bench .. the code is use IEEE.STD_LOGIC_1164.ALL; entity ff_vhdl is Port(a,b : in std_logic_vector(3 downto 0); cin : in std_logic; s: out std_logic_vector(3 downto 0); cout : out std_logic); end ff_vhdl; architecture structural of ff_vhdl is component (...)
Hello, im practicing on my exam to come, and im trying an old exam, i did answer two questions but im very unsure wether they are correct or not, since it was a long time since i wrote vhdl. I would appreciate if someone could check those answers and tell me if something is wrong :). a) using vhdl, implement a component for a full (...)
Hello Dear I want to use some arithmetic operations such as (+,_,*) in my design. The design is fix point. Could you please tell me, If I use (+,_,*) symbols in my vhdl code, is it synthesize correctly or not? Or I need to design the units ( n_bit full adder, for instance) then write the code structurally. ( consider it that, I don't start (...)
# vsim adder.vhdl # Loading C:/Modeltech_5.7e/win32/../win32aloem/convert_hex2ver.dll # ** Error: (vsim-3193) Load of "C:/Modeltech_5.7e/win32/../win32aloem/convert_hex2ver.dll" failed: File not found. # ** Error: (vsim-PLI-3002) Failed to load PLI object file "C:/Modeltech_5.7e/win32/../win32aloem/convert_hex2ver.dll". # Region: / # ** Error:
have a look there , may be it is within : there is to_float() function . Check entier directory for float package.
Hi, members, I've some interview questions about digital circuit, vhdl and ASIC/FPGA. I think it's a good opportunity for us to discuss these questions. Maybe it's very helpful when we want to seek for jobs in the near future. The following is the first quesion. Interview question #1: What are the different adder circuits you studied? Here is m
Hi, I am looking to design a parallel squarer circuit using vhdl and try optimizing interconnections to see if it can be more efiicient. The design template Im looking to follow is based on this