There are 64-way analog signals that are respectively connected with the input ports of four highly precise 16-channel analog switches AD7506 whose enabling signal comes from the other decoder 74HC138. The number of port allotted is 00H-3FH. It is provided in the same way as that of the switching signals . The highest bit of the signal locked that is valid when low voltage is the decoder’s enabling signal . After amplified by highly- precise operational amplifier AD624 and transmitted into voltage of 0-5 V , the analog output signals are selected by the highly precise 8-channel analog switch AD7501, amplified by isolating amplifier AD290, and transmitted into digital signals by analog-to-digital converter ADC0804, then connected to the data bus .
The digital signals are obtained by Hoyle sensor monitoring the rotating speed of the host engine in the cabin[1]. Hoyle sensor has high measuring precision. It can work reliably in seamy conditions of all kinds and send output digitally . Hoyle sensor is connected with the host engine coaxially .A counter detects signals from Hoyle sensor that vary with the rotating speed of the host engine . So the output of the counter stands for the rotating speed of the host engine, once the counting time length is given.
64路模拟信号是由4个高精度16通道模拟信号转换芯片AD7506独自连接的输入端口构成,这个转换芯片能处理来自另一种解码芯片74HC138的信号.端口编码为00H-3FH.转换信号也以同样的方式编号.若低电压为解码器工作的允许信号,信号的最高位被锁定是必要的.经过高精度放大器AD624的放大并输入0-5V电压,高精度8通道模拟转换器AD7501选择模拟输出信号（或是翻译成对模拟信号进行取样）,再经缓冲放大器AD290放大信号,随后经模数转换器ADC0804作用转换为数字信号,最后与数据总线进行连接.
这个数字信号传给霍伊尔传感器以监控船舱内主引擎的转速[1].霍伊尔传感器拥有较高的测量精度.它在各种恶劣的条件下都能可靠的工作,且以数字形式发送输出数据.霍伊尔传感器与主引擎同轴安装.计数器检测来自霍伊尔传感器的信号,这个信号随主引擎转速而变化.因此一旦计数时长给定,计数器的结果即主引擎的转速. There are 64-way analog signals that are respectively connected with the input ports of four highly precise 16-channel analog switches AD7506 whose enabling signal comes from the other decoder 74HC138. The number of port allotted is 00H-3FH. It is provided in the same way as that of the switching signals . The highest bit of the signal locked that is valid when low voltage is the decoder’s enabling signal . After amplified by highly- precise operational amplifier AD624 and transmitted into voltage of 0-5 V , the analog output signals are selected by the highly precise 8-channel analog switch AD7501, amplified by isolating amplifier AD290, and transmitted into digital signals by analog-to-digital converter ADC0804, then connected to the data bus .
The digital signals are obtained by Hoyle sensor monitoring the rotating speed of the host engine in the cabin[1]. Hoyle sensor has high measuring precision. It can work reliably in seamy conditions of all kinds and send output digitally . Hoyle sensor is connected with the host engine coaxially .A counter detects signals from Hoyle sensor that vary with the rotating speed of the host engine . So the output of the counter stands for the rotating speed of the host engine, once the counting time length is given.
64路模拟信号是由4个高精度16通道模拟信号转换芯片AD7506独自连接的输入端口构成,这个转换芯片能处理来自另一种解码芯片74HC138的信号.端口编码为00H-3FH.转换信号也以同样的方式编号.若低电压为解码器工作的允许信号,信号的最高位被锁定是必要的.经过高精度放大器AD624的放大并输入0-5V电压,高精度8通道模拟转换器AD7501选择模拟输出信号（或是翻译成对模拟信号进行取样）,再经缓冲放大器AD290放大信号,随后经模数转换器ADC0804作用转换为数字信号,最后与数据总线进行连接.
这个数字信号传给霍伊尔传感器以监控船舱内主引擎的转速[1].霍伊尔传感器拥有较高的测量精度.它在各种恶劣的条件下都能可靠的工作,且以数字形式发送输出数据.霍伊尔传感器与主引擎同轴安装.计数器检测来自霍伊尔传感器的信号,这个信号随主引擎转速而变化.因此一旦计数时长给定,计数器的结果即主引擎的转速.