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英语翻译Inactualtrafficcontrol,green,yellow,redlightsworkinturncircularly.Accordingtothedifferentphase,theleft-handturnlightofthemasterandslavebrancheschoosetoshowsbetweengreenandyellowlights.Generallyspeaking,thetotal

题目详情
英语翻译
In actual traffic control,green,yellow,red lights work
in turn circularly.According to the different phase,the
left-hand turn light of the master and slave branches
choose to shows between green and yellow lights.
Generally speaking,the total durations of green,left-hand
turn and yellow light equal to the duration of red light.For
the convenience of programming and debugging,the
transition control can be achieved by finite state machine.
The states transition table is shown in table 1.
The number of actual running state is determined by
the input pins of phase selection.The controller receives
new phase setting when the reset signal is valid (state S0).
When number 2 is input by the pins of phase selection,the
order of states changing is S1,S3,S4,S6,and then turn
back to S1.So 2-phase control can be realized.When
number 3 is input,the order of states changing is S1,S2,
S3,S4,S6,and then turn back to S1.3-phase control can
be realized by increasing the left-hand turn phase on
master branches on the basis of 2-phase.When number 4
is input,the order of states changing is S1,S2,S3,S4,S5,
S6,and then turn back to S1.4-phase control can be
realized by increasing the left-hand turn phase on slave
branches on the basis of 3-phase.The translation chart of
states is shown in Figure2.
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答案和解析
在实际的交通控制中,绿色、黄色、红色信号灯依次循环工作.根据不同的相,主支路和从支路的左拐信号灯在绿色和黄色信号灯之间选择来显示.一般来说,绿色、左拐和黄色信号灯的持续时间等于红灯的持续时间.为了编程和调试的方便起见,过渡控制可以用有限状态机来实现.状态过渡表示于表1.
实际运行状态的号码由相选择的输入插针决定.当归零信号有效时(状态S0)控制器接收新的相设定.当由相选择的插针输入号码2时,状态改变的次序为S1、S3、S4、S6,然后转回到S1.因此,2相控制可以实现.当输入号码3时,状态改变的次序为S1、S2、S3、S4、S6,然后转回到S1,通过在2相的基础上,在主支路上增加左拐相就可实现3相控制.当输入号码4时,状态改变的次序为S1、S2、S3、S4、S5、S6,然后转回到S1,通过在3相的基础上,在从支路上增加左拐相就可实现4相控制.状态的过渡表示于图2.