Use Microprogramming to Save Resources and Increase Functionality
IntroductionMicroprogramming is a design approach that every FPGA designer should have in their bag of tricks. I subscribe to the concept that microprogramming is a structured approach to the design of state machines. This is essentially the view of Maurice Wilkes when he first proposed microprogramming in 1951 as an alternative method for the implementation of the control section of a computer. Wilkes was interested in improving the reliability and reducing time needed to implement...
I don’t often convert VHDL to Verilog but when I do ...
VHDL to VerilogI don’t often convert VHDL to Verilog but when I do it is not the most exciting task in the world (that is an understatement). For the most part I am HDL agnostic. Well that is not true, I have a strong preference for MyHDL, and an insubstantial preference for VHDL over Verilog. The choice of HDL for a project is often complicated, irrational, sometimes rational, but most often random. It is often not a choice of the developer - for...
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...
MyHDL Presentation Examples
The last two years I presented at EELive. The first year as an overview of MyHDL and a strong case why you should be using MyHDL as your hardware description language (HDL) [paper]. The second year was an introduction to three alternative HDLs (alt.hdl), including MyHDL. I also presented at a regional Python conferene: pyohio. At the Python conference I presented...
Spline interpolation
A cookbook recipe for segmented y=f(x) 3rd-order polynomial interpolation based on arbitrary input data. Includes Octave/Matlab design script and Verilog implementation example. Keywords: Spline, interpolation, function modeling, fixed point approximation, data fitting, Matlab, RTL, Verilog
IntroductionSplines describe a smooth function with a small number of parameters. They are well-known for example from vector drawing programs, or to define a "natural" movement path through given...
[Comments] C HLS Benefits
Earlier this week I posted a small write-up comparing a hardware median calculation implemented in a C-to gates "HLS" (Vivado C HLS) and a version in MyHDL. For a long time I have had the belief that C-to-gate technologies are of little to no benefit - based on the simple premise that "C" is not that high-level of a language (I actually consider it lower than Verilog and VHDL ... but that is a conversation for another time).
Language comparisons...
Little to no benefit from C based HLS
Last updated 07-Nov-2015
As I write this I am on a plane and my destination is EELive 2014 where I am going to give a talk hardware design: the grunge era. It is a shotgun introduction to three alternative hardware description languages (alt.hdl). The three languages briefly introduced in the talk are: bsv, chisel, and myhdl. The goal of the talk is simply to raise awareness of the three...
Signed serial-/parallel multiplication
Keywords: Binary signed multiplication implementation, RTL, Verilog, algorithm
Summary- A detailed discussion of bit-level trickstery in signed-signed multiplication
- Algorithm based on Wikipedia example
- Includes a Verilog implementation with parametrized bit width
A straightforward method to multiply two binary numbers is to repeatedly shift the first argument a, and add to a register if the corresponding bit in the other argument b is set. The...
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 =...MyHDL @EDAPlayground
Trying out MyHDL became a little easier recently. MyHDL is now avaialbe @EDAPlayground. One can experiment with Python/MyHDL verification of HDL modules and implementing complex digital cirucits in MyHDL.
The @EDAPlayground has two main panels. On the left is the testbench and the right the HDL description to be tested.
There are a couple examples...
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...
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...
Introduction to FPGA Technology
OverviewFPGA stands for Field Programmable Gate Array. An FPGA is an integrated circuit (IC) that can be programmed and configured by the embedded system developer in the field after it has been manufactured. FPGA is a semi-conductor device which is not limited to any pre-defined hardware function; it is rather highly flexible in its functionality and may be configured by the embedded system developer according to his design requirements. FPGAs use pre-built logic blocks and programmable...
Two jobs
For those of you following closely embeddedrelated and the other related sites, you might have noticed that I have been less active for the last couple of months, and I will use this blog post to explain why. The main reason is that I got myself involved into a project that ended up using a better part of my cpu than I originally thought it would.
edit - video of the event:
I currently have two jobs: one as an electrical/dsp engineer recycled as a web publisher and the other...
Sensors Expo - Trip Report & My Best Video Yet!
This was my first time at Sensors Expo and my second time in Silicon Valley and I must say I had a great time.
Before I share with you what I find to be, by far, my best 'highlights' video yet for a conference/trade show, let me try to entertain you with a few anecdotes from this trip. If you are not interested by my stories or maybe don't have the extra minutes needed to read them, please feel free to skip to the end of this blog post to watch the...
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...
How to start in FPGA development? - Simulation software tools
IntroductionThis 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...
Feedback Controllers - Making Hardware with Firmware. Part 4. Engineering of Evaluation Hardware
Following on from the previous abstract descriptions of an arbitrary circuit emulation application for low-latency feedback controllers, we now come to some aspects in the hardware engineering of an evaluation design from concept to first power-up. In due course a complete specification along with application examples will be maintained on the project website.- Part 1: Introduction
- Part 2:...
Project introduction: Digital Filter Blocks in MyHDL and their integration in pyFDA
Hi everyone! After a lot of hesitation and several failed attempts, I have finally entered the world of blogging. A little about myself : My name is Sriyash Caculo and I’m a third year undergrad student at BITS Pilani K.K. Birla Goa Campus pursuing a major in Electronics and Instrumentation engineering. Being an electronics engineer, I developed an interest in Digital Signal Processing and its implementation on hardware.
This blog-post is the first of many to come for the...
Feedback Controllers - Making Hardware with Firmware. Part 7. Turbo-charged DSP Oscillators
This article will look at some DSP Sine-wave oscillators and will show how an FPGA with limited floating-point performance due to latency, can be persuaded to produce much higher sample-rate sine-waves of high quality.Comparisons will be made between implementations on Intel Cyclone V and Cyclone 10 GX FPGAs. An Intel numerically controlled oscillator
Introducing the VPCIe framework
IntroductionMy daily work involves platforms featuring an embedded CPU communcating with a FPGA device over a PCI Express link (PCIe for short). The main purpose of this link is for the CPU to convey configuration, control, and status commands to hardware slaves implemented in the FPGA. For data intensive applications (2D XRay detector readout backend), this link can also be used as a DMA channel to transfer data from the FPGA to the CPU memory. Finally, a slave can interrupt the CPU using...
binary hello world
Python + Ohio + MyHDL + FPGARecently I had the opportunity to coordinate a hands-on programmable hardware (FPGA) workshop (open-space) at a regional Python conference - @pyohio. The workshop was for those that had little to no exposure to programmable hardware. For this situation I used two basic examples: two versions of a binary hello world.
The binary hello world -- blinking an LED -- is a good starting point to introduce programmable hardware, hardware descriptions languages,...
Live Streaming from Embedded World!
For those of you who won't be attending Embedded World this year, I will try to be your eyes and ears by video streaming live from the show floor.
I am not talking improvised streaming from a phone, but real, high quality HD streaming with a high-end camera and a device that will bond three internet connections (one wifi and two cellular) to ensure a steady, and hopefully reliable, stream. All this to hopefully give those of you who cannot be there in person a virtual...
Windows XP and Win32 - the Platform of the Future!
Over the past decade I often wondered why anyone uses Windows. It's just so... proprietary. And pedestrian. As I grew up my OS of choice went nothing to CPM to DOS (on Apple ][), GEM on Atari ST, MS-DOS, DOS extenders, Mac OS, Windows NT, Windows XP, Linux... Now, I again find myself a fan of Windows XP, the platform of the future. (I am still a fan of bare metal, of course).Maybe I am not totally serious, but I, a self-proclaimed freedom lover and...
Feedback Controllers - Making Hardware with Firmware. Part 9. Closing the low-latency loop
It's time to put together the DSP and feedback control sciences, the evaluation electronics, the Intel Cyclone floating-point FPGA algorithms and the built-in control loop test-bed and evaluate some example designs. We will be counting the nanoseconds and looking for textbook performance in the creation of emulated hardware circuits. Along the way, there is a printed circuit board (PCB) issue to solve using DSP.
Fig 1. The evaluation platform
Additional design...
Feedback Controllers - Making Hardware with Firmware. Part 7. Turbo-charged DSP Oscillators
This article will look at some DSP Sine-wave oscillators and will show how an FPGA with limited floating-point performance due to latency, can be persuaded to produce much higher sample-rate sine-waves of high quality.Comparisons will be made between implementations on Intel Cyclone V and Cyclone 10 GX FPGAs. An Intel numerically controlled oscillator
Tools of the Trade: reading PDFs (and keeping bookmarks)
In this article I will take a look at the wonderful MuPDF viewer and present a small modification that saves bookmarks alongside the pdf files, making it infinitely more useful.
Some days I sit down to work and wonder how anything ever gets done. A simple example. When I work on an FPGA design, I wind up with 3 or 4 screens full of documentation, generally in PDF format. There are the Xilinx manuals, the various tool manuals, language reference manuals, you name it. While...
ESC Boston's Videos are Now Up
In my last blog, I told you about my experience at ESC Boston and the few videos that I was planning to produce and publish. Here they are, please have a look and any feedback (positive or negative) is appreciated.
Short HighlightThis is a very short (one minute) montage of some of the footage that I shot at the show & conference. In future shows, I absolutely need to insert clips here and there of engineers saying a few words about the conference (why they...
Project introduction: Digital Filter Blocks in MyHDL and their integration in pyFDA
Hi everyone! After a lot of hesitation and several failed attempts, I have finally entered the world of blogging. A little about myself : My name is Sriyash Caculo and I’m a third year undergrad student at BITS Pilani K.K. Birla Goa Campus pursuing a major in Electronics and Instrumentation engineering. Being an electronics engineer, I developed an interest in Digital Signal Processing and its implementation on hardware.
This blog-post is the first of many to come for the...
Launch of EmbeddedRelated.tv
With the upcoming Embedded Word just around the corner, I am very excited to launch the EmbeddedRelated.tv platform.
This is where you will find the schedule for all the live broadcasts that I will be doing from Embedded World next week. Please note that the schedule will be evolving constantly, even during the show, so I suggest your refresh the page often. For instance, I am still unsure if I will be able to do the 'opening of the doors' broadcast as...