JPH011321A - pulse generator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a pulse generator that receives an analog signal as input and generates a pulse with a frequency proportional to the analog signal value.

(b) Conventional technology In general, conventionally used pulse generators that take in an analog signal as input and output a pulse signal according to the analog signal take in an analog input signal at regular intervals, and , a digital output is output in a logical state of ON or OFF depending on the input value.

(C) Problems to be Solved by the Invention In the conventional pulse generator described above, the digital output and analog input signal acquisition are performed at the same sampling period. It was not possible to generate a pulse. For example, if the sampling period was 100 mm and 5 ec intervals, only pulses of 101 rz or less could be generated.

In view of the above, an object of the present invention is to provide a pulse generator that is capable of outputting a higher frequency, that is, a high-speed pulse, regardless of the analog signal acquisition period.

(d) Means and operation for solving the problem The pulse generator of the present invention captures an analog signal in a first period,
A first timer that outputs a pulse signal with a frequency corresponding to the captured analog signal value, the first timer fixedly defining the first cycle, and a cycle corresponding to the captured analog signal value. The device is characterized in that it includes a second timer that defines , and a pulse output circuit that outputs a pulse signal with a period determined by the second timer. This pulse generator captures an analog signal at a period defined by the first timer. Then, each time this analog signal is taken in, a second period is defined by a second timer according to the analog signal value. In accordance with this cycle, a pulse signal is further output from the output circuit. Therefore, the output of the second timer can be timed up many times during the first period, and therefore a high-speed pulse in which many pulses are output during the first period, that is, the sampling period of the analog signal. A signal can be output.

(e) Examples The present invention will be explained in more detail with reference to Examples below.

<Embodiment 1> FIG. 1 is a circuit block diagram of a pulse generator showing an embodiment of the present invention. In the same figure, the pulse generator is
It consists of an input port 1 that receives analog input signals, a CPU 3, a programmable timer 4, an interrupt controller 5, an output port and an output switching element 7. , are connected by path line 2. The programmable timer 4 also includes a fixed timer I4a that defines the period of the analog input signal, and a timer 114b whose period is variably determined by the input analog signal. The interrupt controller 5 outputs signals pr and p every time the timer I4a and timer ll4b of the programmable timer 4 time up. are received, and the output ρ of timer I4a is
When it receives i, it inputs a 7471 interrupt signal to the CPU 3 and takes in the analog input signal at that point. Also,
Upon receiving the output signal p0 from timer ll4b, timer ■
Send an interrupt signal to CPU3. The CPU 3 outputs a pulse signal of the corresponding period from the output port.

In the pulse generator configured as described above, when the timer I4a of the programmable timer 4 times up [see time tl in FIG. 4(a)], the interrupt of the timer 2 is activated, and as shown in FIG. First, an analog signal is taken in (step 5TI).

That is, in response to the interrupt from the timer I, the CPU 3 receives the analog input signal input at that time through the input port 1 and the pass line 2. Next, the pulse frequency is determined depending on the value of this analog input signal (step 5T2). When the pulse frequency is determined, a timer value of period Tta corresponding to twice the frequency is set in timer ] I4b (step 5T3).

As a result, timer [r4b will be used as timer 14a from now on.
Until the start of the timer, that is, an interrupt occurs, the period ROM is counted, and the interrupt of the timer ■ is input to the interrupt controller 5 [t, I...L in FIG. 4(b)
See t). The interrupt controller 5 inputs this interrupt signal to the CPU 3, and the CPU 3 inverts the previous logic output and outputs it every time there is an interrupt from the timer (2) as shown in FIG. 3 (step 5TII).

Therefore, this signal is derived as an output pulse signal via the output port and switching element 7, and its waveform is input from tl to t2, that is, during the analog sampling period T1, as shown in FIG. 4(c). A pulse signal having a frequency corresponding to the analog signal value is output. Next, when the time reaches L2 from Ll, timer I
4a times up again, and this causes an interrupt from timer 2, so the analog input signal at that point is taken in from input port 1 to CPU 3 as before, and the pulse frequency is determined according to the input data value. For example, if the current analog input signal has a smaller value than the previous one, the frequency will be correspondingly smaller (and the period will also be larger, and the output signal waveform will also be smaller, for example, as shown after L2 in Figure 4). A pulse signal with a long period T z b, that is, a low frequency, is output.

<Embodiment 2> FIG. 5 is a block diagram of a pulse generator showing another embodiment. In this embodiment of the pulse generator, an analog input signal is input to the CPU via an input port 11 and then from a path line 12.
3, the CPU 3 receives an analog input signal from the input port 11 at a fixed period T+ according to the timer interrupt signal Pi output from the timer 114a of the programmable timer 14, and the CPU 3 receives the analog input signal from the input port 11 at a fixed period T+. Determine the pulse frequency according to the signal,
A time corresponding to the pulse frequency is set in the timer l114b of the programmable timer 14.

Timer n14b turns ON10F at the set period.
The switching element 15 is configured to digitally output the F signal.

In this embodiment pulse generator, programmable timer 1
The timer 114a of No. 4 starts the timer 114a every time the timer
This interrupt is input to the CPU 13, and the CPU 3 receives an analog input signal as shown in FIG. 6 every time there is an interrupt of the timer (2) (step 5T21). and,
The pulse frequency is determined from the analog input signal data (step 5T22). That is, when the input data is large, a large frequency is determined accordingly, and conversely, when the input data value is small, a small frequency is determined accordingly. Next, a timer value corresponding to this pulse frequency is set in timer n14b. In other words, in the case of a large frequency, the timer l114
b, and conversely, when the frequency is small, the period of the large period is set in the timer l114b. Therefore, the period corresponding to the analog input signal is set for the timer] 114b. Therefore, as shown in FIG. 7(a), at time L1, timer l14a receives the interrupt of timer I from CP.
When applied to U13, the pulse frequency is determined accordingly. Therefore, as shown in FIG. It will be output.

Then, when the interrupt of the timer 114a, that is, the sampling period arrives, the CPU 3
, through the pass line 12, the analog input signal at that point in time is also taken in, and the frequency corresponding to the analog signal value at that point in time is determined accordingly.
As shown after tz shown in b), a signal with a period Tub corresponding to the input signal value is output. In other words, in the pulse generator of this embodiment as well, every time an analog signal is sampled at an input point due to an interruption of the timer (2), a pulse signal having a frequency corresponding to each input analog signal value is output until the next sampling time.

(f) Effects of the Invention According to this invention, a first timer is provided for defining the acquisition cycle of an analog input signal, and a time corresponding to a frequency cycle corresponding to the input analog signal value is further defined. It is equipped with a second timer and an output circuit that outputs a pulse signal with a period specified by the second timer, and since the analog signal acquisition period and the output pulse period are independent, the analog signal It is possible to generate a pulse signal with a period smaller than the acquisition period of , that is, at a high speed, and it is possible to output a high-speed pulse signal with a frequency much higher than the analog sampling period.

[Brief explanation of the drawing]

FIG. 1 is a circuit block diagram showing Embodiment 1 of the present invention;
FIG. 2 is a flowchart showing the interrupt of timer I to explain the operation of the pulse generator, FIG. 3 is a flowchart showing the interrupt of timer II, and FIG. A waveform diagram for explaining the operation of the pulse generator of the same embodiment, FIG. 5 is a block diagram showing the configuration of the second embodiment of the present invention,
FIG. 6 is a flow diagram showing an interrupt of timer 1 to explain the operation of the pulse generator, and FIG. 7 is a waveform diagram to explain the operation of the pulse generator. 1.ll: input port, 2.12: pass line. 3.13: Cr'U. 4.14: Programmable timer. 4a/14a: Timer I, 4b-14b: Tie? I
I. 6: Output port. 7.15: Output switching element. Patent applicant Shimadzu Corporation Representative Patent attorney Shigeru Nakamura Figure 2 Figure 3 Figure 4 Figure 6 Figure 7 t, r2

Claims (1)

[Claims] (1) A pulse generator that captures an analog signal in a first cycle and outputs a pulse signal with a frequency corresponding to the captured analog signal value, the first pulse generator fixedly defining the first cycle. a second timer that defines a cycle according to the captured analog signal value, and a pulse output circuit that outputs a pulse signal with a cycle that is defined by the second timer. A pulse generator featuring: