JPH0246038A - Data linking system - Google Patents

Abstract

PURPOSE:To prevent from taking in erroneous input information to a linking master station even when it is transmitted to the linking master station at the time of turning off a switch for power supply in data linking by providing an external power voltage detecting circuit to detect the lowering of a power voltage and noticing the status information of hardware abnormality to the linking master station. CONSTITUTION:When a power switch 7 is turned off from on, an output V1 of a direct current power supply 4, an output V3 of a DC/DC converter 9 and the input information level of a control circuit 11 act in the same way as usual instances. Then, the action of an external power voltage detecting circuit 16 detects the fact that the power switch 7 is turned off from on at a voltage higher than the voltage value of an input information discriminating level 10V of the control circuit 11 when the output V1 of the direct current power supply 4 is down, and it sets '0' to status S1 of the control circuit 11. Thus, even when the erroneous input information from ON to OFF of a switch group 14 for input information are set to data D1-D8 for the output holding time t2 of the DC/DC converter 9, a linking master station 1 does not take in the data but ignores them.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a sequencer data link system including a link master station and a plurality of distributed input stations.

(Prior Art) FIG. 4 is a block diagram showing a conventional sequencer data link system, in which (1) is a link master station, (2) and (3) are distributed input stations, and (4) is a link master station.

(5) is a DC power supply, (6) to (8) are power switches, and the above distributed input stations (2) and (3) are connected to each other based on the turning on of power switches (7) and (8), respectively. A DC/OC converter (9), (to) that drops a predetermined set voltage value V output from the DC power supply (4), (5), and this converter (9),
(10) operates in response to the supply of a predetermined set voltage v2 output from the DC power supply (4), (5), and inputs the supply voltage value V, which is equal to or higher than the predetermined discrimination level, from the DC power supply (4) or (5). It has control circuits (11) and (12) that take in human input information from the switch by receiving it via the groups (14) and (ts), and connects the link master station (1) to the signal transmission line (13). It is designed to be connected through and transmit data.

Next, the operation will be explained. When the power switch (6) is turned on, AC power is supplied to the link master station (1), and the FLAG and data DI to D1B, which indicate the start of link data shown in FIG. 5, are all "0" and the statuses Sl and S.
2, for example, the link data of °O'' is the link master station (
1) is periodically transmitted from the OUT terminal. When the power switches (7) and (8) are inserted, the DC power supplies (4) and (5) are activated, and for example, the set voltage V,
= DC24V is output, distributed human power side (2) and
(3) is supplied to the power input terminal, and the internal [IC/
D(: Converter (9) and (lO) are used to convert the voltage down to control circuits (11) and (12) with ν2=5ν
When power is supplied to GNP+ and GNP+, it operates as follows.

That is, input information switch groups (14), (15
) is the DC power supply (4), (5) and the distributed human power side (2
) and (3) common terminals (COMI, C0M2) and input terminals (Xi to (12) and stored internally. On the other hand, the link data transmitted from the OUT terminal of the link master station (1) is transmitted to the IN terminal of the distributed human power side (2) via a signal transmission line (13) such as an optical fiber cable or signal transmission wire, and is input to the distributed input. layer (2)
If it is set to one station, the previously stored human power information is placed in the link data DI to D8 of one station. For example, the switch group (14) that is turned on is
The data of “1” is set here, and the data that is not input is set to “0”.
”, and when the distributed input layer (2) is operating normally, “°1” is placed on the status Sl within the control circuit (11), and if the hardware is abnormal, O′.These link data are output from the OUT terminal of the distributed human power side (2).Also, since the link master station (1) is connected to the IN terminal of the distributed input layer (3), the distributed human power side If side (3) is set to 2 stations, in the same way, link data D9 of 2 stations is set.
The data of the switch group (15) is placed in ~016, and the hardware abnormality signal is also placed in status S2. Since these link data are transmitted from the 01lT terminal of the distributed input layer (3) to the link master station (1), the distributed human power side (
The manual information and hardware abnormalities in 2) and (3) can be transmitted to the link master station (1) only through the signal transmission line (13) such as an optical fiber cable or signal transmission wire. Incidentally, by installing the distributed input layers (2) and (3) as close as possible to the human information switch group (14) and (15), wiring labor and construction can be saved.

[Problem to be Solved by the Invention] However, in the conventional data link system, for example, when the power switch (7) of the DC power supply (4) is turned from on to off while the link system is in operation, as shown in FIG. , after the output holding time tl of the DC power supply (4), its output reaches the input information discrimination level V2 (
For example, Ov) or below, while D
The output V of the C/DC converter (9) also goes down, but not at the same time, and the internal elements of the control circuit (11) operate during the output holding time t2 of the DC/DC converter (9). The link master station (1) has the problem of transmitting input information to the link master station (1) due to the erroneous switching of the input information switch group (14) from on to off. .

This invention was made to solve the above-mentioned problems, and even if incorrect manual information is transmitted to the link master station when the power to the distributed input layer is turned off, the link master station will not be able to retrieve this data. The purpose is to obtain a data link system that does not involve any interference.

[Means to solve the problem]

The data link system according to the present invention includes a DC/DCC/type converter that drops a predetermined set voltage value output from a DC power supply based on turning on a power switch, and a predetermined set voltage value output from this converter. A control circuit that operates in response to a voltage supply and receives input information from the input information switches by receiving a supply voltage value equal to or higher than a predetermined discrimination level supplied from the DC power supply through the input information switch group. In a data link system in which multiple input layers are connected to a link master station via signal transmission lines to transmit data, the output voltage of the DC power supply is detected, and an abnormality is detected at least while the output voltage of the DC power supply drops to the input information discrimination level of the control circuit. It is equipped with an external power supply voltage detection circuit that sends out a number.

(Operation) In this invention, even if incorrect manual information is transmitted to the link master station when the power of the distributed input station is turned off during link communication, the external power supply voltage detection circuit detects this and the hardware malfunctions. Since the mask station is notified of this, the link master station does not import the data at this time.

[Embodiment] Hereinafter, an embodiment of the present invention will be described with reference to the block diagram of FIG. 1, in which the same parts as in FIG. 4 are denoted by the same reference numerals.

In Figure 1, (16) and (17) are DC power supply (4)
, (5) and outputs an abnormal signal while the output voltage of the control circuits (11) and (12) falls to the human power information discrimination level v2. The voltage detection circuit sets the input information discrimination level V2 to a set voltage v4 of 10V or more and +24V or less, for example, output v1 of the DC power supply (4) to 15V or less.
When the linkage level decreases, an abnormal signal is transmitted to the link master station (1) via the control circuit (11).

The other configurations are the same as the conventional example.

The basic operation in the above configuration is exactly the same as the conventional example.

When the power switch (7) is turned from on to off, the output v1 of the DC power supply (4) and the DC/
DCC/formula-ta (9) output v3 and control circuit (11
) operates in the same way as the conventional example, but the operation of the external power supply voltage detection circuit (16) provided in this embodiment is such that when the output V of the DC power supply (4) goes down, the control circuit It detects quickly that the power switch (7) is turned off from on at a voltage higher than the input information discrimination level (IOV) of (11), and sets 0'' to the status Sl of the control circuit (11). , DC/DCC/formula-ta
Even if erroneous human power information from ON to OFF of the human power information switch group (14) is placed on data D1 to D8 during the output holding time t2 of (9), the link master station (1) will not accept this data. Just ignore it.

In the above embodiment, the set voltage value for sending out the abnormality signal of the external power supply voltage detection circuit (16) was set higher than the human power information discrimination level of the control circuit (11), but as shown in FIG. ) is provided with a delay circuit inside the control circuit (11
The same effect can be obtained by delaying the point in time when the input information level of ) becomes equal to or less than the discrimination level by a predetermined delay time t3.

In this case, the set voltage value of the external power supply voltage detection circuit (16) can be set to the same value as the human power information discrimination level of the control circuit (11), and the normality of data before delay time t3 can be set to the same value as the human power information discrimination level of the control circuit (11). ensure and confirm the nature of the

〔Effect of the invention〕

As described above, according to the present invention, it is possible to notify the link master station of hardware abnormality status information by providing an external power supply voltage detection circuit that detects a drop in power supply voltage. Even if erroneous input information is transmitted to the link master station when switching from on to off, the link master station has the effect of not taking in this data and being able to ignore it.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing one embodiment of the present invention, Fig. 2 is an internal timing chart in Fig. 1, Fig. 3 is a timing chart according to another embodiment, and Fig. 4 is a data link system of a conventional sequencer. FIG. 5 is an explanatory diagram of an example of link data output from a link master station, and FIG. 6 is an internal timing chart in a conventional example. (1) is the link master station, (2) and (3) are distributed input stations, (4) and (5) are DC power supplies, (6) to (8) are power switches, (9) and (10) is DC/[IG converter, (H
), (12) is a control circuit, (13) is a signal transmission line, and (14) and (15) are a group of input information switches. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] a DC/DC converter that drops a predetermined set voltage value output from a DC power supply based on turning on of a power switch; A distributed input station having a control circuit that receives input information from the switches by receiving a supply voltage value higher than a predetermined discrimination level supplied from the input information switch group via a group of input information switches, and connects a signal transmission line to the link master station. A data link system that connects a plurality of devices and transmits data through the external power supply voltage detection circuit, which detects the output voltage of the DC power supply and sends out an abnormality number at least while the output voltage of the DC power supply drops to a level for determining input information of the control circuit. A data link system characterized by: