Class: GBRb::CPU::ConcatenatedRegister

Inherits:
Object
  • Object
show all
Defined in:
lib/gbrb/cpu/concatenated_register.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(high, low) ⇒ ConcatenatedRegister

Returns a new instance of ConcatenatedRegister.



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 5

def initialize high, low
  @high = high
  @low = low
  @bits = @high.bits + @low.bits
end

Instance Attribute Details

#bits ⇒ Object (readonly)

Returns the value of attribute bits.



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 42

def bits
  @bits
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 25

def == other
  other.read == read && other.bits == bits
end

#clear ⇒ Object 



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 37

def clear
  @high.clear
  @low.clear
end

#half_mask ⇒ Object 



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 33

def half_mask
  @half_mask ||= 0x10 ** (@bits/8)
end

#mask ⇒ Object 



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 29

def mask
  @mask ||= 0x10 ** (@bits/4)
end

#read ⇒ Object 



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 17

def read
  @low.read + (@high.read << @high.bits)
end

#store(value) ⇒ Object 



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 11

def store value
  value &= mask - 1
  @high.store value >> @high.bits
  @low.store value << @low.bits >> @low.bits
end

#zero? ⇒ Boolean

Returns:



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# File 'lib/gbrb/cpu/concatenated_register.rb', line 21

def zero?
  @low.zero? && @high.zero?
end