Copyright	(C) 2015-2016 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	Unsafe
Language	Haskell2010
Extensions	ScopedTypeVariables BangPatterns ViewPatterns DataKinds InstanceSigs StandaloneDeriving DeriveDataTypeable DeriveFunctor DeriveTraversable DeriveFoldable DeriveGeneric DefaultSignatures DeriveLift DerivingStrategies FlexibleContexts MagicHash KindSignatures TupleSections TypeOperators ExplicitNamespaces ExplicitForAll BinaryLiterals TypeApplications

Clash.Prelude.ROM.File

Contents

Asynchronous ROM
Synchronous ROM synchronized to an arbitrary clock
Internal

Description

Initializing a ROM with a data file

ROMs initialized with a data file. The BNF grammar for this data file is simple:

FILE = LINE+
LINE = BIT+
BIT  = '0'
     | '1'

Consecutive LINEs correspond to consecutive memory addresses starting at 0. For example, a data file memory.bin containing the 9-bit unsigned number 7 to 13 looks like:

We can instantiate a synchronous ROM using the content of the above file like so:

f :: HiddenClock dom  => Signal dom (Unsigned 3) -> Signal dom (Unsigned 9)
f rd = unpack <$> romFile d7 "memory.bin" rd

And see that it works as expected:

>>> import qualified Data.List as L
>>> L.tail $ sampleN 4 $ f (fromList [3..5])
[10,11,12]

However, we can also interpret the same data as a tuple of a 6-bit unsigned number, and a 3-bit signed number:

g :: HiddenClock dom  => Signal dom (Unsigned 3) -> Signal dom (Unsigned 6,Signed 3)
g rd = unpack <$> romFile d7 "memory.bin" rd

And then we would see:

>>> import qualified Data.List as L
>>> L.tail $ sampleN 4 $ g (fromList [3..5])
[(1,2),(1,3)(1,-4)]

Synopsis

asyncRomFile :: (KnownNat m, Enum addr) => SNat n -> FilePath -> addr -> BitVector m
asyncRomFilePow2 :: forall n m. (KnownNat m, KnownNat n) => FilePath -> Unsigned n -> BitVector m
romFile :: (KnownNat m, KnownNat n, HiddenClock dom, HiddenEnable dom) => SNat n -> FilePath -> Signal dom (Unsigned n) -> Signal dom (BitVector m)
romFilePow2 :: forall n m dom. (KnownNat m, KnownNat n, HiddenClock dom, HiddenEnable dom) => FilePath -> Signal dom (Unsigned n) -> Signal dom (BitVector m)
asyncRomFile# :: KnownNat m => SNat n -> FilePath -> Int -> BitVector m

Asynchronous ROM

asyncRomFile Source #

Arguments

:: (KnownNat m, Enum addr)
=> SNat n	Size of the ROM
-> FilePath	File describing the content of the ROM
-> addr	Read address `rd`
-> BitVector m	The value of the ROM at address `rd`

An asynchronous/combinational ROM with space for n elements

NB: This function might not work for specific combinations of code-generation backends and hardware targets. Please check the support table below:

               | VHDL     | Verilog  | SystemVerilog |
===============+==========+==========+===============+
Altera/Quartus | Broken   | Works    | Works         |
Xilinx/ISE     | Works    | Works    | Works         |
ASIC           | Untested | Untested | Untested      |
===============+==========+==========+===============+

Additional helpful information:

See Clash.Prelude.ROM.File for more information on how to instantiate a ROM with the contents of a data file.
See Clash.Sized.Fixed for ideas on how to create your own data files.
When you notice that asyncRomFile is significantly slowing down your simulation, give it a monomorphic type signature. So instead of leaving the type to be inferred:
```
myRomData = asyncRomFile d512 "memory.bin"
```
or giving it a polymorphic type signature:
```
myRomData :: Enum addr => addr -> BitVector 16
myRomData = asyncRomFile d512 "memory.bin"
```
you should give it a monomorphic type signature:
```
myRomData :: Unsigned 9 -> BitVector 16
myRomData = asyncRomFile d512 "memory.bin"
```

asyncRomFilePow2 Source #

Arguments

:: (KnownNat m, KnownNat n)
=> FilePath	File describing the content of the ROM
-> Unsigned n	Read address `rd`
-> BitVector m	The value of the ROM at address `rd`

An asynchronous/combinational ROM with space for 2^n elements

NB: This function might not work for specific combinations of code-generation backends and hardware targets. Please check the support table below:

               | VHDL     | Verilog  | SystemVerilog |
===============+==========+==========+===============+
Altera/Quartus | Broken   | Works    | Works         |
Xilinx/ISE     | Works    | Works    | Works         |
ASIC           | Untested | Untested | Untested      |
===============+==========+==========+===============+

Additional helpful information:

See Clash.Prelude.ROM.File for more information on how to instantiate a ROM with the contents of a data file.
See Clash.Sized.Fixed for ideas on how to create your own data files.
When you notice that asyncRomFilePow2 is significantly slowing down your simulation, give it a monomorphic type signature. So instead of leaving the type to be inferred:
```
myRomData = asyncRomFilePow2 "memory.bin"
```
you should give it a monomorphic type signature:
```
myRomData :: Unsigned 9 -> BitVector 16
myRomData = asyncRomFilePow2 "memory.bin"
```

Synchronous ROM synchronized to an arbitrary clock

romFile Source #

Arguments

:: (KnownNat m, KnownNat n, HiddenClock dom, HiddenEnable dom)
=> SNat n	Size of the ROM
-> FilePath	File describing the content of the ROM
-> Signal dom (Unsigned n)	Read address `rd`
-> Signal dom (BitVector m)	The value of the ROM at address `rd` from the previous clock cycle

A ROM with a synchronous read port, with space for n elements

NB: Read value is delayed by 1 cycle
NB: Initial output value is undefined

NB: This function might not work for specific combinations of code-generation backends and hardware targets. Please check the support table below:

               | VHDL     | Verilog  | SystemVerilog |
===============+==========+==========+===============+
Altera/Quartus | Broken   | Works    | Works         |
Xilinx/ISE     | Works    | Works    | Works         |
ASIC           | Untested | Untested | Untested      |
===============+==========+==========+===============+

Additional helpful information:

See Clash.Prelude.ROM.File for more information on how to instantiate a ROM with the contents of a data file.
See Clash.Sized.Fixed for ideas on how to create your own data files.

romFilePow2 Source #

Arguments

:: (KnownNat m, KnownNat n, HiddenClock dom, HiddenEnable dom)
=> FilePath	File describing the content of the ROM
-> Signal dom (Unsigned n)	Read address `rd`
-> Signal dom (BitVector m)	The value of the ROM at address `rd` from the previous clock cycle

A ROM with a synchronous read port, with space for 2^n elements

NB: Read value is delayed by 1 cycle
NB: Initial output value is undefined

NB: This function might not work for specific combinations of code-generation backends and hardware targets. Please check the support table below:

               | VHDL     | Verilog  | SystemVerilog |
===============+==========+==========+===============+
Altera/Quartus | Broken   | Works    | Works         |
Xilinx/ISE     | Works    | Works    | Works         |
ASIC           | Untested | Untested | Untested      |
===============+==========+==========+===============+

Additional helpful information:

See Clash.Prelude.ROM.File for more information on how to instantiate a ROM with the contents of a data file.
See Clash.Sized.Fixed for ideas on how to create your own data files.

Internal

asyncRomFile# Source #

Arguments

:: KnownNat m
=> SNat n	Size of the ROM
-> FilePath	File describing the content of the ROM
-> Int	Read address `rd`
-> BitVector m	The value of the ROM at address `rd`

asyncROMFile primitive