serial_add_behav Architecture Reference

Behavioral and structural architechture for serial_adder. More...

Processes
serial_adder_state_transition	( reset , clk )
	State transition process. When reset is active state machine is in the cout_0 state.
serial_adder_next_state_logic	( carry_out )
	Next state process. When calculated carry is 0 the next state is cout_0 state, otherwise the next state is cout_1 state.

Components
fulladder	<Entity fulladder>

Types
state_type	( cout_0 , cout_1 )
	Definition of states of serial_adder state machine. See detailed description for more details.

Signals
state_reg	state_type
next_state	state_type
carry_out	std_logic
carry_in	std_logic

Instantiations
fa	fulladder <Entity fulladder>

Detailed Description

Serial adder is realized as simple state machine shown in Fig. 1. It has two states, cout_0 and cout_1. For binary addition serial adder instantiates fulladder component and its inputs are serial inputs a_s and b_s, while its output sum is sum_s. Input signals change at every rising edge of clk signal. Input carry should be the output carry from previous calculation. Input carry is determined by the current state of the state machine. These states define two possible situations: cout_0 is the state when input carry (previous output carry) is equal to 0, while cout_1 is the state when input carry (previous output carry) is equal to 1.

Fig. 1. Serial adder state machine and coresponding signals with fulladder instance.

Definition at line 54 of file serial_adder.vhd.

Member Function Documentation

serial_adder_next_state_logic()

serial_adder_next_state_logic (   carry_out   )

Process

Definition at line 92 of file serial_adder.vhd.

serial_adder_state_transition()

serial_adder_state_transition	(		reset,
			clk
	)

Definition at line 82 of file serial_adder.vhd.

Member Data Documentation

carry_in

carry_in std_logic

Signal

Definition at line 63 of file serial_adder.vhd.

carry_out

carry_out std_logic

Signal

Definition at line 62 of file serial_adder.vhd.

fa

fa fulladder

Instantiation

Definition at line 79 of file serial_adder.vhd.

fulladder

fulladder

Component

Definition at line 66 of file serial_adder.vhd.

next_state

next_state state_type

Signal

Definition at line 60 of file serial_adder.vhd.

state_reg

state_reg state_type

Signal

Definition at line 60 of file serial_adder.vhd.

state_type

state_type ( cout_0 , cout_1 )

Type

Definition at line 57 of file serial_adder.vhd.

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The documentation for this class was generated from the following file:

• serial_adder.vhd