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Hardcaml Logo Hardcaml Web IDE

Introduction

Hardcaml Web IDE is a browser-based environment for learning and experimenting with hardware design using Hardcaml, Jane Street’s OCaml library for digital circuit design.

What is Hardcaml?

Section titled “What is Hardcaml?”

Hardcaml is a powerful library for describing, simulating, and generating digital hardware. It provides:

  • Type-safe circuit descriptions - Catch errors at compile time
  • Simulation - Test your circuits without physical hardware
  • Waveform visualization - See signal behavior over time
  • RTL generation - Export to Verilog for synthesis
  • Much More!

What can you do here?

Section titled “What can you do here?”

Learn Hardcaml

Section titled “Learn Hardcaml”

Work through interactive tutorials that teach you hardware design concepts using real, runnable code.

Complete Nand2Tetris

Section titled “Complete Nand2Tetris”

Implement the Part 1 of the Nand2Tetris course in Hardcaml - build a computer from NAND gates up to a CPU!

Experiment

Section titled “Experiment”

Try out circuit ideas quickly without any local setup. The IDE compiles and simulates your code in the cloud.

Quick Example

Section titled “Quick Example”

Here’s a simple 8-bit counter:

open! Core
open! Hardcaml
open! Signal


module I = struct
  type 'a t = { clock : 'a; clear : 'a; enable : 'a }
  [@@deriving hardcaml]
end


module O = struct
  type 'a t = { out : 'a [@bits 8] }
  [@@deriving hardcaml]
end


let create scope (i : _ I.t) : _ O.t =
  let spec = Reg_spec.create ~clock:i.clock ~clear:i.clear () in
  let counter = reg_fb spec ~width:8 ~f:(fun fb ->
    mux2 i.enable (fb +:. 1) fb)
  in
  { out = counter }
;;


let hierarchical scope =
  let module Scoped = Hierarchy.In_scope (I) (O) in
  Scoped.hierarchical ~scope ~name:"counter" create
;;

Try it out in the IDE!

Next Steps

Section titled “Next Steps”