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Examples under vhdl.
Run all examples, which have assertions in them:
cd vhdl
./runFiles:
- Examples
- Basic
- vhdl/hello_world_tb.vhdl: hello world
- vhdl/min_tb.vhdl: min
- vhdl/assert_tb.vhdl: assert
- Lexer
- vhdl/comments_tb.vhdl: comments
- vhdl/case_insensitive_tb.vhdl: case insensitive
- vhdl/whitespace_tb.vhdl: whitespace
- vhdl/literals_tb.vhdl: literals
- Flow control
- vhdl/procedure_tb.vhdl: procedure
- vhdl/function_tb.vhdl: function
- vhdl/operators_tb.vhdl: operators
- Types
- vhdl/integer_types_tb.vhdl: integer types
- vhdl/array_tb.vhdl: array
- vhdl/record_tb.vhdl.bak: record. TODO fails with "GHDL Bug occurred" on GHDL 1.0.0
- vhdl/generic_tb.vhdl: generic
- vhdl/package_test_tb.vhdl: Packages
- vhdl/standard_package_tb.vhdl: standard package
- textio
* vhdl/write_tb.vhdl: write
* vhdl/read_tb.vhdl: read - vhdl/std_logic_tb.vhdl: std_logic
- vhdl/stop_delta_tb.vhdl:
--stop-delta
- Basic
- Applications
- Combinatoric
- vhdl/adder.vhdl: adder
- vhdl/sqrt8_tb.vhdl: sqrt8
- Sequential
- vhdl/clock_tb.vhdl: clock
- vhdl/counter.vhdl: counter
- Combinatoric
- Helpers
* vhdl/template_tb.vhdl: template
List of similar feeling films: www.youtube.com/watch?v=zwYwFoanrNg 11 Underrated Hard Sci-fi Movies by Marvelous Videos (2021)
There is only a very fine difference between a very good film, and the best films of all time. Perhaps it is something to do on how epic the subject matter is? It is often very hard to tell, and switches between the categories are also possible.
web.archive.org/web/20181119214326/https://www.bipm.org/utils/common/pdf/CGPM-2018/26th-CGPM-Resolutions.pdf gives it in raw:The breakdown is:
- the unperturbed ground state hyperfine transition frequency of the caesium-133 atom is 9 192 631 770 Hz
- the speed of light in vacuum c is 299 792 458 m/s
- the Planck constant h is 6.626 070 15 × J s
- the elementary charge e is 1.602 176 634 × C
- the Boltzmann constant k is 1.380 649 × J/K
- the Avogadro constant NA is 6.022 140 76 × mol
- the luminous efficacy of monochromatic radiation of frequency 540 × 1012 Hz, Kcd, is 683 lm/W,
- actually use some physical constant:
the unperturbed ground state hyperfine transition frequency of the caesium-133 atom is 9 192 631 770 Hz
Defines the second in terms of caesium-133 experiments. The beauty of this definition is that we only have to count an integer number of discrete events, which is what allows us to make things precise.the speed of light in vacuum c is 299 792 458 m/s
Defines the meter in terms of speed of light experiments. We already had the second from the previous definition.the Planck constant h is 6.626 070 15 × J s
the elementary charge e is 1.602 176 634 × C
- arbitrary definitions based on the above just to match historical values as well as possible:
the Boltzmann constant k is 1.380 649 × J/K
the Avogadro constant NA is 6.022 140 76 × mol
the luminous efficacy of monochromatic radiation of frequency 540 × 1012 Hz, Kcd, is 683 lm/W
One very good thing about this is that it makes it easy to create test cases directly in C++. You just supply inputs and clock the simulation directly in a C++ loop, then read outputs and assert them with
assert(). And you can inspect variables by printing them or with GDB. This is infinitely more convenient than doing these IO-type tasks in Verilog itself.Some simulation examples under verilog.
First install Verilator. On Ubuntu:Tested on Verilator 4.038, Ubuntu 22.04.
sudo apt install verilatorRun all examples, which have assertions in them:
cd verilator
make runFile structure is for example:
- verilog/counter.v: Verilog file
- verilog/counter.cpp: C++ loop which clocks the design and runs tests with assertions on the outputs
- verilog/counter.params: gcc compilation flags for this example
- verilog/counter_tb.v: Verilog version of the C++ test. Not used by Verilator. Verilator can't actually run out
_tbfiles, because they do in Verilog IO things that we do better from C++ in Verilator, so Verilator didn't bother implementing them. This is a good thing.
Example list:
- verilog/negator.v, verilog/negator.cpp: the simplest non-identity combinatorial circuit!
- verilog/counter.v, verilog/counter.cpp: sequential hello world. Synchronous active high reset with active high enable signal. Adapted from: www.asic-world.com/verilog/first1.html
- verilog/subleq.v, verilog/subleq.cpp: subleq one instruction set computer with separated instruction and data RAMs
Bibliography:
- Something Ventured (2011) documentary
Companies have been really slow to support SVG features in their browsers, and that is very saddening: medium.com/@michaelmangial1/introduction-to-scalable-vector-graphics-6450c03e8d2e
You can't drop SVG support for
canvas until there's a way to run untrusted JavaScript on the browser!SVG does have some compatibility annoyances, notably SVG fonts. But we should as a society work to standardize and implement a fix those, the benefits of SVG are just too great!
Examples:
- svg/svg.svg a minimal somewhat sane SVG:
- if the
widthandheightproperties were not given, you get the default 300x150, which seems to be set in the SVG standard:
- if the
- how to add na SVG image to a HTML file:
- svg/svg.html: external image. The included file is svg/svg.svg.
- svg/inline.html: inline.
- svg/billion-laughs.svg
- svg/html.svg
- svg/triangle.svg
- svg/viewBox.svg: this attribute allows you to control the default SVG
svg width=andheight=while keeping the coordinates of the drawing untouched. If theviewBoxaspect ratio differs from the width/height ratio, you likely want to play withpreserveAspectRatio, otherwise you would get white spaces by default on the generated image - CSS with SVG:
- svg/style.svg: inline CSS
- svg/style-external.svg: external CSS with:
<?xml-stylesheet type="text/css" href="svg.css" ?>, see also: stackoverflow.com/questions/18434094/how-to-style-svg-with-external-css- svg/subdir/style-external.html: is the relative CSS relative to the HTML or to the SVG? Answer: to the SVG... OMG. So how to make it work reliably?
- svg/current-color.html and svg/current-color.svg: illustrates
fill="currentColor". Only works for inline SVG however... See also: stackoverflow.com/questions/13000682/how-do-i-have-an-svg-image-inherit-colors-from-the-html-document/13002311
- JavaScript with SVG:
- svg/defs.html hows how
defsworks- svg/defs-external.html tries to include external
defsfrom svg/defs.svg, but that fails like everything else related to external SVGs
- svg/defs-external.html tries to include external
Diffeomorphic to the 3 sphere.
The complex analogue of the special orthogonal group, i.e. the subgroup of the unitary group with determinant equals exactly 1 instead of an arbitrary complex number with absolute value equal 1 as is the case for the unitary group.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact