# Designing a Pseudorandom Noise Generator

#### VEDELAGO!!

Joined May 8, 2007
6
Hello Everybody,

First of all, FANTASTIC site - Everything is well explained.

Anyway I'm new here and thought I'd ask a question and just get some clarification on whether I'm headed on the right path.

I was given the task described in the title for an assignment. Now, I've done a search on the message board forums, and to my knowledge (and searching skillz ) I don't believe this question has been asked previously.

I have to design this Pseudorandom Noise Generator using The Hardware Description Language Called ABEL. Now I've done alot of searching and reading and have concluded that the only way i would be able to achieve this would be through a linear feedback shift register. I'm very unsure on how to implement one of these in ABEL or if using a LFSR is the right way to go about it

My questions are:

1.) Will using a LFSR with a series of XOR gate feedback functions produce a Pseudorandom Noise Generator?

2.) Does anyone have any ideas/links/code examples/text references on how to design a LFSR (Or Pseudorandom Noise Generator) using ABEL?

I apologize if this question has been previously asked, i did run a search using the forums' search engine prior to submitting this post.

Anyways thanks in advance and Keep up the fantastic work with the site and forum

Regards, VEDELAGO!!

I should Further Clarify that i am to implement this into a Development board designed by Lattice called M4A5.

#### Papabravo

Joined Feb 24, 2006
20,600
An LFSR will produce a pseudorandom sequence with a period that can approach 2^n where n is the number of stages. The sequence cannot be longer than 2^n states and might be much shorter.

#### VEDELAGO!!

Joined May 8, 2007
6

Okay, so i use a LFSR to produce the pseudorandom sequence. My question is, does anyone know how to implement a LFSR in ABEL code? Do i use a series of flipflops and if so? How do i code THEM in ABEL?

Thanks again.

- VEDELAGO!!

#### John Luciani

Joined Apr 3, 2007
475
The Art of Electronics by Horowitz and Hill ISBN: 0521370957
has a section on pseudo-random bit sequences.

(* jcl *)

#### VEDELAGO!!

Joined May 8, 2007
6
Thanks John

#### 2216_8

Joined May 16, 2007
1
Hmmm, it seems you are in my CC2510 class