VGA Output in 7 Slices. Really.
Ridiculous? Read on - I will show you how to generate VGA timing in seven XilinxR Spartan3R slices.Some time ago I needed to output video to a VGA monitor for my Apple ][ FPGA clone. Obviously (I thought), VGA's been done before and all I had to do was find some Verilog code and drop it into my design. As is often the case (with me anyway), the task proved to be very different from my imagined 'couple of hours to integrate the IP'.I found some example code for my board. I...
How to start in FPGA development? - Simulation software tools
Introduction
This post is related to the first post How to start in FPGA development? - Some tips which aimed to show other options to work on the simulation of your project. In this first approach will be explained some advantages and disadvantages of using Xilinx ISE (+ModelSim) or using ModelSim, Precision and Xilinx ISE. And finally my opinion of which are the ones I...
MyHDL FPGA Tutorial II cont. (Echo, Audio Interface)
Introduction
To demonstrate the echo on an FPGA board an interface to an audio ADC/DAC chip will be used. The following will explain the connection to the audio codec and the HDL module used to interface.
Audio Codec InterfaceI have two boards with TI AIC23b audio codecs. The AIC23 has a configuration interface (ability to program the registers) and a streaming audio interface. The SPI mode will be used to configure the codec and the I2S interface is used to send and...
FPGA Assemblers and Time Machines
Flashback to 1986. A young man has a crazy idea - he wants to make a CPU all by himself. He is reading early Xilinx manuals cover to cover as if they were novels. Yes, you are quick - this is indeed a (mostly) true story about me and my dream, suddenly made possible by this new FPGA technology.
Sadly more than 20 years went by before my first CPU ran in a Xilinx FPGA. Why did it take so long? Every few years I set up the tools and every time I walked away, scared silly. As the years...
How to start in FPGA development? - Some tips
IntroductionThe aim of this tutorial is to show some useful tips for people like me that one day started from zero to work with FPGA's. Why FPGA's? Because they are easy to use and they are not too expensive, and they are usually used in lab courses to let students "play" with them.
1: How to choose the right FPGA?As you may know there are a lot of different FPGA's, brands and models. How to choose the right one? It's very difficult to say that before knowing which will be the...
MyHDL FPGA Tutorial II (Audio Echo)
IntroductionThis tutorial will walk through an audio echo that can be implemented on an FPGA development board. This tutorial is quite a bit more involved than the previous MyHDL FPGA tutorial. This project will require an FPGA board with an audio codec and the interface logic to the audio codec.
Review the Previous TutorialThe previous MyHDL FPGA tutorial I posted a strobing LED on an FPGA board. In that tutorial we introduced the basics of a MyHDL module....
An Editor for HDLs
Unless you're still living in the '90s and using schematics, your FPGA designs are entered into text files as VHDL or Verilog source. Which, of course, implies you're using some form of text editor. Now, right after brace placement in C, the choice of an editor is the topic most likely to incite a nerd civil war (it's a bike-shed issue). I won't attempt to influence your choice because it really makes no difference to me. But if you are using the same editor I do, then maybe I can help you...
Are you kidding me?
If I understand the blog entry [1] correctly, it's saying the industry is ready for high level synthesis (HLS), well almost. The blog states, the higher abstraction level will be achieved via C/C++/SystemC (the C-centric flows). A quote from the blog.
... getting close, and one of the biggest hurdles still to overcome is the skill set -- the combination of hardware design expertise and C++ -- ...
C/C++/SystemC, are you kidding...
Designing a FPGA Micro Pt2 - Clock and Counter build and test.
So last time I looked and talked about designing my own PIC12F509. I concluded by talking shortly about the clock that is used inside the chip. If you have not read this it may be a good time to jump back and read what I have written so far. I’ll be putting links back at the top of every blog from now on to help.State Machine ‘v’ Micro in a FPGADesigning a FPGA Micro Pt1 - Start The ClockOk so this last week I started writing the VHDL code for my PIC core that I’ll be...
Designing a FPGA Micro Pt1 - Start The Clock
Last time I talked about state machines and micro’s inside FPGAs and why you may want to consider having a micro. So lets say you have decided you want or need a micro in your FPGA design. Where will you start? Well there are lots to pick from but one option is to design your own. So with that in mind I decided to set myself the challenge of doing just that.
MyHDL Resources and Projects
Last updated 07-Nov-2017
MyHDL ResourcesIf you want to dive into MyHDL (digital hardware description in Python) there are many resources available. Below is a list of MyHDL resources, including some of the past blogs here on fpgarelated.
The MyHDL manual is a great (probably the best) place to get started.
The manual is an in-depth introduction to MyHDL. The concepts are well explained and there are examples to test while working through the...
The New Forum is LIVE!
After months of hard word, I am very excited to introduce to you the new forum interface.
Here are the key features:
1- Easily add images to a post by drag & dropping the images in the editor
2- Easily attach files to a post by drag & dropping the files in the editor
3- Add latex equations to a post and they will be rendered with Mathjax (tutorial)
4- Add a code snippet and surround the code with
Point of View
I was caught of guard when someone commented:
"when a FIR filter is full of multiple loops and complex code, something is wrong"The comment was made during an informal discussion on alternative hardware description languages (HDL) and was targeted to the straightforward FIR filter implemented in MyHDL:
(different FIR description simulation results)
Personally, (and...
Polynomial Math
Elliptic Curve Cryptography is used as a public key infrastructure to secure credit cards, phones and communications links. All these devices use either FPGA's or embedded microprocessors to compute the algorithms that make the mathematics work. While the math is not hard, it can be confusing the first time you see it. This blog is an introduction to the operations of squaring and computing an inverse over a finite field which are used in computing Elliptic Curve arithmetic. ...
Mathematics and Cryptography
The mathematics of number theory and elliptic curves can take a life time to learn because they are very deep subjects. As engineers we don't have time to earn PhD's in math along with all the things we have to learn just to make communications systems work. However, a little learning can go a long way to helping make our communications systems secure - we don't need to know everything. The following articles are broken down into two realms, number theory and elliptic...
Choosing an Implementation Approach
What one man can do, another can do!--The Edge (1997) Choose the hill you want to die on.--Common saying attributed to the United States Marine Corps Planning out an FPGA Implementation
In my first article, I gave a high-level view of the project that brings me into the world of FPGA development. At the end, I tried to break down the areas of development that would be involved, and some of the knowledge and expertise I would probably have to gain in order to make it a...
One Clock Cycle Polynomial Math
Error correction codes and cryptographic computations are most easily performed working with GF(2^n)
Finally got a drone!
As a reader of my blog, you already know that I have been making videos lately and thoroughly enjoying the process. When I was in Germany early this summer (and went 280 km/h in a porsche!) to produce SEGGER's 25th anniversary video, the company bought a drone so we could get an aerial shot of the party (at about the 1:35 mark in this video). Since then, I have been obsessing on buying a drone for myself and finally made the move a few weeks ago - I acquired a used DJI...
Are you kidding me?
If I understand the blog entry [1] correctly, it's saying the industry is ready for high level synthesis (HLS), well almost. The blog states, the higher abstraction level will be achieved via C/C++/SystemC (the C-centric flows). A quote from the blog.
... getting close, and one of the biggest hurdles still to overcome is the skill set -- the combination of hardware design expertise and C++ -- ...
C/C++/SystemC, are you kidding...
Elliptic Curve Key Exchange
Elliptic Curve Cryptography is used to create a Public Key system that allows two people (or computers) to exchange public data so that both sides know a secret that no one else can find in a reasonable time. The simplest method uses a fixed public key for each person. Once cracked, every message ever sent with that key is open. More advanced key exchange systems have "perfect forward secrecy" which means that even if one message key is cracked, no other message will...
One Clock Cycle Polynomial Math
Error correction codes and cryptographic computations are most easily performed working with GF(2^n)
PicoBlaze - Program RAM Access for an Interactive Monitor
I have a confession to make: I love PicoBlaze! There are many reasons to love it. It is a tiny CPU (96 Spartan3 slices or 26 Spartan6 slices plus a BRAM). It is simple. It is bug-free. It's pretty fast. It can reduce the size and the complexity of your design - instead of debugging a big state machine, just throw one (or more) of these in. Add a serial output and you can debug your fpga from inside out!However, there are a few problems. The...
Designing Embedded Systems with FPGA-2
In last part, we created hardware design of basic system. The next step is to generate (compile) hardware design. Compiled hardware design is known as bit-stream andstored in *.bit file. To compile hardware, use hardware->generate hardware tab. The complete hardware design generation takes several seconds to several minutes depending on computer speed and design complexity. In back ground, the whole design process involves many different steps including synthesis, placement, routing and...
MyHDL Interface Example
MyHDL Interfaces ExampleWith the next release of MyHDL, version 0.9, conversion of interfaces will be supported. In this context an interface is any object with a Signal attribute. This can be used to simplify connection between modules and port definitions. For example, if I want to define a simple memory-map bus, the Signals for the bus can be defined as follows:
class BareBoneBus: def __init__(self): self.wr = Signal(False) self.rd =...Polynomial Inverse
One of the important steps of computing point addition over elliptic curves is a division of two polynomials.
New Discussion Group: DSP & FPGA
I have just created a new discussion group for engineers implementing DSP functions on FPGAs. The creation of this group has been on my todo list for a long time. If you want to join the group, send a blank email to: fpgadsp-subscribe@yahoogroups.com
As usual, it should take a few weeks before there are enough members for interesting discussions to get started.
Designing a FPGA Micro Pt1 - Start The Clock
Last time I talked about state machines and micro’s inside FPGAs and why you may want to consider having a micro. So lets say you have decided you want or need a micro in your FPGA design. Where will you start? Well there are lots to pick from but one option is to design your own. So with that in mind I decided to set myself the challenge of doing just that.
State Machine ‘v’ Micro in a FPGA
Designing a system and considering if to have a FPGA in the first place is something a engineer should always consider. However one thing that people look to do is designing a microcontroller on a FPGA and in this post I want to consider why we would do it at all and what would be the real consideration for doing this.
We first look at what's available in the microcontroller world. We have a vast range from tiny 8bit 6 pin devices right the way up to monster 32bit devices. These...
