MyHDL hardware design language encased in the tasty PygMyHDL wrapper.
PygMyHDL is a thin wrapper around MyHDL. MyHDL lets you design and simulate digital hardware using Python. PygMyHDL does the same thing, but tries to make it a little simpler. Think of it as “MyHDL on training wheels”. Once you get enough experience with PygMyHDL, you’ll probably cast it aside and just use straight MyHDL. That’s OK; that’s why I invented it.
PygMyHDL adds the following features to MyHDL:
- Wire and Bus classes for declaring single-bit and multi-bit digital signals.
- Bus objects have .o and .i properties that are used to get the value on a bus (that’s the .o property) and to drive values onto a bus (using the .i property).
- State objects are used to declare state variables for finite-state machines. Each State object also stores all the defined states in its s attribute for use in making comparisons to states or updating state values.
- The @chunk decorator is used to indicate a function will create one or more pieces of logic circuitry. These pieces will be implicitly gathered into a list of logic instances that can be simulated and synthesized later. (MyHDL requires you to explicitly store logic instances into Python variables so they can be found and processed later.)
- The decorators @comb_logic and @seq_logic are used to declare functions that perform combinational and sequential logic operations, respectively. (These are almost identical to MyHDL’s @always_comb and @always_seq decorators except they assist with the implicit instantiation of logic.)
- Helper functions are provided for testing a digital design using random test vectors, exhaustive test vectors, user-defined test vectors, or a simple clock signal.
- The myhdlpeek module is used to display the results of logic simulations as waveforms or tables.
Below are some examples of Jupyter notebooks using PygMyHDL. Unfortunately, the Github Notebook viewer doesn’t render the waveform displays so you’ll have to download and run the notebooks locally or click on the static HTML link to see what PygMyHDL can do.
- The Fastest, Easiest FPGA Blinker, Ever!: [Notebook1] [HTML1]
- Hierarchy and Abstraction and Ursidae, Oh My!: [Notebook2] [HTML2]
- Pulse Width Modulators: [Notebook3] [HTML3]
- Block (RAM) Party!: [Notebook4] [HTML4]
- FSMs Without Monsters!: [Notebook5] [HTML5]
- Free software: MIT license
- Added State object for working with finite-state machines in PygMyHDL.
- Fixed Bus object so my_bus.o[m:n] now calls my_bus(m, n) to get a shadow slice instead of creating an array of wires.
- First release on PyPI.