JPS62133369A - Level sensor for self-diagnosis of electronic equipment - Google Patents

Abstract

PURPOSE:To confirm the normal operation of electric equipment at any time by inputting a detected signal level to a CPU with sampling pulses which operate at the timing of a system controller and judging its normality or abnormality. CONSTITUTION:A sound recording and a video recording signal, a CTL signal, a detected signal Vi1 regarding whether the breaking of a wire occurs to a recording head or not are compared by a comparator 11 with a reference voltage Vref and when the signal Vi1 exceeds the level of the voltage Vref, the comparison output A triggers a D/FF 12. Consequently, the Q output of the FF 12 goes up to an H level and the value is held and also inputted to a CPU 41. Then, the FF 12 is reset with sampling pulses C which are sent out of the CPU 41 at proper intervals to the sensor 10. Then when the signal Vi1 rises above the voltage Vref, the CPU 41 records a logical value 1 without fail. The frequency of this logical value 1 is monitored by respective sensors at specific intervals to judge the normality or abnormality of the detected signal, thereby confirming the operation of the electric equipment.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides an electronic device that automatically determines whether or not it is in a normal operating state, and based on the result, displays an abnormal location. The present invention also relates to a level sensor for self-diagnosis of electronic equipment such as stopping operation.

[Summary of the invention]

The self-diagnosis level sensor of the present invention includes a comparison base that compares a detected signal with a reference voltage, and a latch that outputs a first logical value when the comparison base detects a detected signal of a predetermined level. A circuit is provided, and the output of the latch circuit is read out at a predetermined cycle using a sampling signal from a control unit (CPU) for determining whether the detected signal is normal or abnormal. Therefore, it is possible to easily construct a level sensor that uses a microcomputer to determine whether or not the signal to be detected is normal depending on the content of the detected signal.

[Conventional technology]

High-grade electronic A-bases, such as VTRs (magnetic recording and reproducing devices) for broadcasting stations, are indispensable devices for news gathering, recording and editing of broadcast content, and their drive control is essential. In most cases, it is built-in and controlled by a C6 microcontroller (user).

Then, using the microcomputer 11I, for example, check the installation status of the tape reel, the signal to be recorded, the normality or abnormality of the tape reel, the presence or absence of a disconnection accident of the tape reel, recording or not.
Monitoring of C and T L signals 1 Detect the servo status etc. from the C, / S or circuit signals and check whether these are normal or not 1r? It is preferable to input this information into a built-in microcomputer so that normal operating conditions can be easily checked at all times.

In this case, if the detected signal No. 4 is a control signal with little fluctuation, it is usually sufficient for the cap to monitor its output level, so for example, as shown in FIG.
is input to a peak level detector formed by an operational amplifier l, a 2° f-ode, and a capacitor 3'g, and the output of this peak level detector is set as a reference voltage Vr, .
+ is applied to comparator 4, and the CPU
Convert it to the logical level for manual input, and connect it from manual port 5 to C.
Macro computer (CPU) via PU bus 6
7 may be input.

If such a monitoring system is constructed as part of a program that performs system control of the CPU,
It is possible to display malfunctioning parts of the VTR and give instructions on how to deal with them, so you can prevent accidents such as failure to cover important news sources or damage to valuable recorded content due to incorrect operation or malfunction of the equipment. It will be possible to prevent this from happening.

[Problem that the invention seeks to solve]

However, level sensors that employ peak hold circuits as described above are good when there are no large level fluctuations in the detected signal or when the signal waveform is simple, but they monitor level fluctuations in the detected signal to determine whether it is normal. When there is a need to determine abnormalities, there is a problem in terms of the reliability of detected values, and at the same time there is also a problem in that it is not possible to follow level fluctuations in a fast cycle.

Therefore, it is conceivable to convert the fluctuations in the detected signal into a digital signal using a sampling method and input it to the CPU, but in this case, the circuit scale becomes large and costs increase, and at the same time It is difficult to supply a sampling clock using an analog circuit such as the one shown in FIG.

The present invention has been made in view of the above points, and is capable of forming logical values for various detected signals using a simple circuit so that the CPU can easily determine whether the signal level is normal or abnormal. The present invention provides a level sensor for self-cutting.

[A useless child actor who solves problems and concerns]

The level sensor for self-diagnosis of the present invention includes a comparison circuit that compares a reference voltage and the signal to be detected, and a launch circuit that holds a first logic value when a detection signal of the comparison circuit is output. When a sampling pulse (search pulse) output from the CPU is inputted to the 1171 latch circuit, the held logical value is taken into the CPU and reset.

[Effect]

The form of the detected signal obtained from the monitoring circuit of electronic equipment or the monitoring sensor differs depending on the signal to be monitored, but when using the level sensor described above, the detected signal with large fluctuations and Sampling pulses can be supplied from the CPU at an appropriate frequency according to the detected signal with a small number of signals, and based on the level information of the detected signal obtained at that time, it is possible to accurately determine whether the detected signal is normal or abnormal. Therefore, it becomes possible to perform continuous rotation while constantly checking the normal operation of the electronic device.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of a self-cutting level sensor for electronic equipment according to the present invention.
The portions 0, 20, 3o are the detected signals V + 1. V
i2. V i:i, shows the part of the level sensor to which is input.

Each level sensor 10, 20, 30 has a comparator 1.
1, 21, 31, D-flip-flop 12.22 (2
3), input port 13, 23 (33), output port 14
．． 24 (34) are provided, and each CPU/<
It is connected to a control unit (CPU) 41 via a bus 40 .

The CPU 41 is composed of a system controller that centrally controls the drive control of electronic devices.
In the case of R, control programs such as tape running mode setting, recording/111 raw/editing, control, servo control, time need sending, etc. are built-in.

The signal to be detected Vin includes the recording, recording signal, CTL signal, and time coat transmission supplied to each input terminal.
There is a servo signal (for monitoring the recording current level) to check for disconnection of the REC (recording) head, and these signals are manually input to each level sensor 10°20.30. Hereinafter, the detection operation of each detected signal will be explained with reference to the second example.

The detected signal V + 1 is compared with a reference voltage vre in a comparator 11 in the level sensor, and the reference voltage Vr...
When the level of " is exceeded, the comparison output A triggers the D flip-flop 12. Therefore, the D flip-flop 1
The Q output of No. 2 is at the "H" level, holds that value (waveform B), and is taken into the CPU 41. CPU
41 to each level sensor 10, 20.30 at appropriate intervals.
Flip-flop 12 is reset.

Therefore, when the detected signal v1n reaches a level greater than )1 (quasi-voltage Vref), the CPU 41 always records the logical value "l";
By monitoring the frequency of the signal at predetermined intervals, it is possible to determine whether the detected signal is normal or abnormal.

The determination of normality or abnormality may be determined based on the type of signal to be detected and its characteristics. For example, when determining the presence or absence of a disconnection in the recording head, a longer pitch may be used than when determining the presence or absence of a recording signal.

In addition, time code monitoring, CTL signal monitoring, etc. are done by Shu JI.
JI (7) Set to monitor using short sampling pulses.

In this way, it is sufficient to use sampling pulses that match the timing of the system controller.
It doesn't need to be fast.

The level sensor for self-diagnosis of electronic equipment according to the present invention includes a plurality of level sensors 10 for each detection location as described above.
, 20, 30. The normal level of the detected signal held in each level sensor is sequentially fetched into the CPU at predetermined intervals, and the normal level of the detected signal is checked.
This eliminates the need to use a capacitor for peak level detection in the level sensor, and at the same time, it is possible to detect the normality of the level of a detected signal with rapid level fluctuations using a simple circuit. It can be judged appropriately.

In addition, the sampling period can be set to match the timing of the electronic device's system controller, so high-speed A/D
Since a converter, memory, etc. are unnecessary and the level sensor is simplified, it becomes easy to provide self-diagnosis functions at multiple points.

〔Effect of the invention〕

As explained below, the electric power of this invention is
The level sensor for K uses a sampling pulse that operates at the timing of the system controller to accurately capture the level of the detected signal into the CPU and determine whether it is normal or abnormal. In addition to being simplified, it has the effect of being able to sufficiently follow even small level fluctuations. Therefore, it is possible to provide a system that monitors multiple items such as checking the human output level and checking the operating status of equipment at a low cost, which has the advantage of improving the reliability of electrical equipment. .

[Brief explanation of drawings]

Fig. 1 is a block diagram of a level sensor for self-diagnosis showing an embodiment of the present invention, Fig. 2 is a waveform diagram of the main part of -F in Fig. 1, and Fig. 3 is a diagram of a conventional peak hold detection circuit. The circuit diagram of the level sensor is shown. In the figure, 10, 20.30 are level sensors, 11.21.
31 is a comparator, 12.22 is a D flip-flop (latch circuit), 13.23 is an input port, 14.24 is an output port, 40 is a CPU bus, and 41 is a CPU (control unit). Level sensor block diagram Figure 2

Claims (1)

[Claims] a comparison circuit into which a reference voltage and a detected signal are input; a latch circuit which holds a first logical value according to the detection signal of the comparison circuit; and when a sampling pulse from the CPU is input to the latch circuit, the It comprises an input/output port that imports a first logical value into the CPU and then resets it, and is configured such that the CPU determines the presence or absence of the detected signal based on the frequency of the imported first logical value. Level sensor for self-diagnosis of electronic equipment.