超声波外文翻译

超声波外文翻译内容摘要：

is greater than 25mV, the output from the high jump 8 feet into a lowlevel, as interrupt request signals to the singlechip processing. Ranging in front of singlechip termination circuit output port INT0 interrupt the highest priority, right or left location of the output circuit with output gate IC3A access INT1 port singlechip, while singlechip and P1. 4 received input IC3A, interrupted by the process to identify the source of inquiry to deal with, interrupt priority level for the first left right after. Part of the source code is as follows: receive1: push psw push acc clr ex1。 related external interrupt 1 jnb , right。 pin to 0, ranging from right to interrupt service routine circuit jnb , left。 pin to 0, to the left ranging circuit interrupt service routine return: SETB EX1。 open external interrupt 1 pop acc pop psw reti right: ...。 right location entrance circuit interrupt service routine Ajmp Return left: ...。 left Ranging entrance circuit interrupt service routine Ajmp Return The calculation of ultrasonic propagation time When you start firing at the same time start the singlechip circuitry within the timer T0, the use of timer counting function records the time and the launch of ultrasonic reflected wave received time. When you receive the ultrasonic reflected wave, the receiver circuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates a signal, singlechip microputer in response to external interrupt request, the implementation of the external interrupt service subroutine, read the time difference, calculating the distance . Some of its source code is as follows: RECEIVE0: PUSH PSW PUSH ACC CLR EX0。 related external interrupt 0 MOV R7, TH0。 read the time value MOV R6, TL0 CLR C MOV A, R6 SUBB A, 0BBH。 calculate the time difference MOV 31H, A。 storage results MOV A, R7 SUBB A, 3CH MOV 30H, A SETB EX0。 open external interrupt 0 POP ACC POP PSW RETI For a flat target, a distance measurement consists of two phases: a coarse measurement and. a fine measurement: Step 1: Transmission of one pulse train to produce a simple ultrasonic wave. Step 2: Changing the gain of both echo amplifiers according to equation , until the echo is detected. Step 3: Detection of the amplitudes and zero。