Copyright	(C) 2013-2016 University of Twente 2017 Google Inc. 2019 Myrtle Software Ltd
License	BSD2 (see the file LICENSE)
Maintainer	Christiaan Baaij <christiaan.baaij@gmail.com>
Safe Haskell	Safe
Language	Haskell2010

Clash.Prelude.Moore

Contents

Moore machine

Description

Whereas the output of a Mealy machine depends on current transition, the output of a Moore machine depends on the previous state.

Moore machines are strictly less expressive, but may impose laxer timing requirements.

Synopsis

moore :: (HiddenClockResetEnable dom, Undefined s) => (s -> i -> s) -> (s -> o) -> s -> Signal dom i -> Signal dom o
mooreB :: (HiddenClockResetEnable dom, Undefined s, Bundle i, Bundle o) => (s -> i -> s) -> (s -> o) -> s -> Unbundled dom i -> Unbundled dom o
medvedev :: (HiddenClockResetEnable dom, Undefined s) => (s -> i -> s) -> s -> Signal dom i -> Signal dom s
medvedevB :: (HiddenClockResetEnable dom, Undefined s, Bundle i, Bundle s) => (s -> i -> s) -> s -> Unbundled dom i -> Unbundled dom s

Moore machine

moore Source #

Arguments

:: (HiddenClockResetEnable dom, Undefined s)
=> (s -> i -> s)	Transfer function in moore machine form: `state -> input -> newstate`
-> (s -> o)	Output function in moore machine form: `state -> output`
-> s	Initial state
-> Signal dom i -> Signal dom o	Synchronous sequential function with input and output matching that of the moore machine

Create a synchronous function from a combinational function describing a moore machine

macT
  :: Int        -- Current state
  -> (Int,Int)  -- Input
  -> Int        -- Updated state
macT s (x,y) = x * y + s

mac
  :: HiddenClockResetEnable dom
  => Signal dom (Int, Int)
  -> Signal dom Int
mac = moore mac id 0

>>> simulate @System mac [(0,0),(1,1),(2,2),(3,3),(4,4)]
[0,0,1,5,14,30,...
...

Synchronous sequential functions can be composed just like their combinational counterpart:

dualMac
  :: HiddenClockResetEnable dom
  => (Signal dom Int, Signal dom Int)
  -> (Signal dom Int, Signal dom Int)
  -> Signal dom Int
dualMac (a,b) (x,y) = s1 + s2
  where
    s1 = moore mac id 0 (bundle (a,x))
    s2 = moore mac id 0 (bundle (b,y))

mooreB Source #

Arguments

:: (HiddenClockResetEnable dom, Undefined s, Bundle i, Bundle o)
=> (s -> i -> s)	Transfer function in moore machine form: `state -> input -> newstate`
-> (s -> o)	Output function in moore machine form: `state -> output`
-> s	Initial state
-> Unbundled dom i -> Unbundled dom o	Synchronous sequential function with input and output matching that of the moore machine

A version of moore that does automatic Bundleing

Given a functions t and o of types:

t :: Int -> (Bool, Int) -> Int
o :: Int -> (Int, Bool)

When we want to make compositions of t and o in g using moore, we have to write:

g a b c = (b1,b2,i2)
  where
    (i1,b1) = unbundle (moore t o 0 (bundle (a,b)))
    (i2,b2) = unbundle (moore t o 3 (bundle (c,i1)))

Using mooreB however we can write:

g a b c = (b1,b2,i2)
  where
    (i1,b1) = mooreB t o 0 (a,b)
    (i2,b2) = mooreB t o 3 (c,i1)

medvedev :: (HiddenClockResetEnable dom, Undefined s) => (s -> i -> s) -> s -> Signal dom i -> Signal dom s Source #

Create a synchronous function from a combinational function describing a moore machine without any output logic

medvedevB :: (HiddenClockResetEnable dom, Undefined s, Bundle i, Bundle s) => (s -> i -> s) -> s -> Unbundled dom i -> Unbundled dom s Source #

A version of medvedev that does automatic Bundleing