Class: HDLRuby::High::Std::ArbiterT

Inherits:
Object
  • Object
show all
Defined in:
lib/HDLRuby/std/sequencer_sync.rb

Overview

Describes an arbiter for a shared signal.

Direct Known Subclasses

PriorityArbiterT

Instance Method Summary collapse

Constructor Details

#initialize(name, *sigs) ⇒ ArbiterT

Create a new arbitrer named +name+ for shared signals +sigs+.



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# File 'lib/HDLRuby/std/sequencer_sync.rb', line 128

def initialize(name,*sigs)
    # Sets the name.
    name = name.to_sym
    @name = name
    # Register the signals.
    @signals = []
    # Adds the signals.
    self.(*sigs)
    # Create the set of access points.
    @size = 0
    @points = {}
    # Create the acquire/release bit vector.
    acquires = nil
    HDLRuby::High.cur_system.open do
        acquires = [1].inner(HDLRuby.uniq_name(:"#{name}_acq") => 0)
    end
    @acquires = acquires
    # Register the arbiter.
    this = self
    HDLRuby::High.space_reg(name) { this }
end

Instance Method Details

#<=(val) ⇒ Object

Arbiter access code generation: 1 for acquire and 0 for release.



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# File 'lib/HDLRuby/std/sequencer_sync.rb', line 183

def <=(val)
    # Add an access point if required.
    point = self.add_point
    # Do the access.
    @acquires[point] <= val
end

#add_point ⇒ Object

Adds an access point.



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# File 'lib/HDLRuby/std/sequencer_sync.rb', line 161

def add_point
    # Maybe a point already exist for current sequencer.
    sequ = SequencerT.current
    point = @points[sequ]
    return point if point
    # No add it.
    point = @size
    @points[sequ] = point
    @size += 1
    # Resize the acquire vector according to the new point.
    @acquires.type.instance_variable_set(:@range,0..point)
    return point
end

#call(*sigs) ⇒ Object

Adds the signals.



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# File 'lib/HDLRuby/std/sequencer_sync.rb', line 151

def call(*sigs)
    sigs.each do |sig|
        unless sig.is_a?(SharedSignalI) then
            raise "An arbitrer only works on a shared signal, not a #{sig.class}"
        end
        @signals << sig
    end
end

#select(point) ⇒ Object

Shared signal selection code generation.



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# File 'lib/HDLRuby/std/sequencer_sync.rb', line 176

def select(point)
    @signals.each do |signal|
        signal.select(@points.key(point))
    end
end