Package: icemu
# ICemu - Emulate Integrated Circuits`icemu` is a Python library that emulates integrated circuits at the logic level. For example,if you want to simulate a circuit with a decoder driving the clock pin of two shift registers,it would look like this:dec = SN74HC138()sr1 = CD74AC164()sr2 = CD74AC164()mcu_pin = OutputPin('PB4')sr1.pin_CP.wire_to(dec.pin_Y0)sr2.pin_CP.wire_to(dec.pin_Y1)sr1.pin_DS1.wire_to(mcu_pin)sr2.pin_DS1.wire_to(mcu_pin)print(dec.asciiart())_______A>|-   +|>Y7B>|-   +|>Y6C>|-   +|>Y5G2A>|-   +|>Y4G2B>|-   +|>Y3G1>|+   +|>Y2Y0<|-___+|>Y1You could then play with pins at your heart contents and have them "propagate" through wires and IClogic automatically.## See it in actionHere's a little video of the simulated `seg7` example (see `examples` folder):[![asciinema](https://asciinema.org/a/LCF3EGRiJFK1LzXwn2R6XUgGb.png)](https://asciinema.org/a/LCF3EGRiJFK1LzXwn2R6XUgGb)and here is the video of the **exact same code** running in real life![![vimeo](https://i.vimeocdn.com/video/662736875_677x.jpg)](https://vimeo.com/239693641)## What is it forThe goal of this library is to facilitate the testing and debugging of embedded software. When werun software on an embedded prototype, it's often hard to debug failures because we don't evenknow if the problem comes from hardware (wiring, it's always the wiring!) or software. Moreover,testing directly on a prototype often involves significant setup time.With emulation, we have a quick setup time, introspection capabilities, all this stuff. We can thenconfirm the soundness of our logic before sending it to our prototype.### Killer feature: direct integration with your codeIf you have a circuit with a microcontroller in it, you can simulate the circuit by **directlyplugging the code you're putting on the MCU** in it. See examples.### Comparison with Verilog/VHDLBeing new to the world of electronics, I don't know much about full blown simulation solutions.However, from what I read about Verilog and VHDL, these tools seem to be about helping to design**circuits**.ICemu's goal is not that! Its goal is to help you debug the software you're going to flash on yourMCU. Python being easily hooked to C, you can, with a little abstraction layer, directly run yourcode on the simulator and debug it there.What I've read about simulations on Verilog/VHDL simulators is that you supply it with a series ofinputs you want to send to your circuits. That's insufficient! What I want to do is run my whole,complex software and have **it** supply the inputs and react to the outputs of my simulated circuit.There's a possibility that my newbie-ness made me create a tool that already exists, however, andif that happened, please tell me so I can stop working on useless tools.## Why PythonBecause it's used for debugging purposes, speed is not essential. Also, Python is easy to gluewith C.I've tried writing quick `icemu` prototype in C and Rust, but they were needlessly complicated.With Python, it's easy to write the software and add new chips. Because there's gonna be a *lot*of these chips to add, we might as well make this process as fast as possible.## How to useYou can install `icemu` with pip on python **3.4+**:$ pip install --user icemuThen, you need to recreate your prototype's logic in a small Python program that uses `icemu` andwrap that into easy to use functions. Those functions should be designed to receive pin statechange from the MCU and apply the logic change into your circuit. Make that program print relevantinformation so that you can assert your logic's soundness.Then, write yourself a small Hardware Abstraction Layer at the pin/register level, embed yourPython program like a regular C application would do, make your `ifdef`ed functions call helperfunctions you've written in your Python program, compile and run!## ExamplesThere are examples in the `examples` folder. Follow instructions in the README file of each example.## LicenseLGPLv3, Copyright 2017 Virgil Dupras