JPS63141158A - Electronic device provided with plural electronic circuit boards - Google Patents

Abstract

PURPOSE:To easily detect the overlapped selection of an electronic circuit board due to the abnormality of address allocation on an electronic circuit board side, by detecting a current value between the electronic circuit board selected by an address signal and a board selecting device. CONSTITUTION:On each of the electronic circuit boards 2, a constant current circuit 5 on which a prescribed current flows only when the said board is selected by the address signal from a selection means 1 is provided, and the selection means 1 is connected to the constant current circuit 5 with a common line 6. When one electronic circuit board 2 is selected by the selection means 1, the current value which flows on the common line 6 stays at the prescribed value, however, if two or more electronic circuit boards are selected due to the overlapped allocation, the current value on the common line 6 becomes different from the prescribed value. At this time, the change of the current value is detected by a current detecting means 7 which detects a current amount on the common line 6, and the overlapped allocation of the electronic circuit board is displayed on an overlap display part 8.

Description

[Detailed Description of the Invention] [Summary] In an electronic device including a plurality of identical electronic circuit boards,
This is a duplication detection device that detects duplicate selection of boards due to an address assignment error on the electronic circuit board side based on a current value flowing between a board selected by an address signal and a board selection device.

[Industrial application field]

The present invention is applicable to an electronic device that is equipped with a plurality of identical electronic circuit boards and uses only one board at the same time based on an address signal from a board selection device, particularly in an electronic exchange, where address assignments of the electronic circuit boards are duplicated. The present invention relates to an electronic device that includes a plurality of electronic circuit boards that detect whether or not a computer is present.

[Conventional technology]

Conventionally, an electronic device equipped with a plurality of electronic circuit boards with the same specifications has, for example, a shelf (box) containing 20 to 30 electronic circuit boards (puff cages). There is an electronic switchboard that is mounted on a single board.

This electronic exchange controls the puff cages in a time-sharing manner, and as shown in FIG. By using the connected data line 3 and address line 4, data can be taken into only one of the n packages 2 at a certain point in time. That is, the data is distributed to all n packages 2 by the data line 3, but the data is distributed to all n packages 2 by the data line 3.
The address signal flowing through is applied to an address comparison circuit 9 that detects whether the address of the package 2 matches, and only the package 2 whose address signal matches the value assigned in advance by the switch 9a is synchronized with the address signal. The matched signal 5YNC is output as the signal *9b, and the package 2 takes in data from the data line 3 based on this -defeat signal 5YNC.

However, if you simply output the address signal and select one package 2 without checking anything, if there is an error (duplication) in the value assigned by the switch 9a on the electronic circuit board, a problem will occur. The address signal that selects package 2 (for example, ll5) is
(For example, field 7) may also be pulled in at the same time, and there is a risk that data will be captured in both and a failure will occur.

Therefore, as shown in FIG. 3, the signal line 9b to which the one-defeat signal 5YNC of each package 2 is output is led out to the check terminal C provided in the package 2 by a branch signal line 9c, and the check line 16 is connected to this terminal C. and connect the other ends of these check lines 16 to 1 provided in the board selection device 1, for example.
The 1/n detector 1 is connected to the /n detector 17 to detect that the coincidence signal 5YNC comes from only one of the zero check lines 16 from the n packages 2 at a given time.
It has been considered to detect duplication of address assignments by detecting the address assignment using the method 7. In this method, check l4
When the one-defeat signal 5YNC appears on only one of the IA 16, no signal is output from the 1/n detector 17, but the match signal 5YNC appears on two or more of the check lines 16.
appears, the duplicate allocation detection signal from the 1/n detector 17 is held in the flip-flop 18, and the flip-flop 18 drives the alarm 19,
The display device (for example, an LED) 20 is turned on, and the allocation abnormality is recognized.

[The invention solved the problem: 1 > Bi 1 Ro 16' (74:, ) However, in the conventional method, one check line 16 is required for each package 2, so the large capacity (high density) of the electronic exchange With this trend, the number of packages 2 connected to one exchange has increased, and the number of check lines 16 has also increased, creating a physical limit on the number of connectors on electronic circuit boards. Also, there is no problem with configuring the check line 16 with a wire, but recently the data vA3 and address line 4, including the check line 16, are connected to the back of the package 2.
Pattern wiring is now being done using printed circuit boards (called backboards). In such a case, the fourth
Terminal D located at the same position in each package 2 as shown in the figure.
Data line 3 to connect to 1~Dns Al~An
The address lines 4 and 4 can be formed as parallel lines on the printed circuit board 'll1I5, but when attempting to connect the check terminals C, which are also located at the same position, on the printed circuit board 15 by printed wiring, the printed circuit board 15
Since 20 to 30 patterns had to be formed on the printed circuit board 15, pattern wiring was physically impossible except by increasing the size of the printed circuit board 15, which was disadvantageous in terms of space and cost.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the conventional electronic devices equipped with a plurality of electronic circuit boards. To provide an electronic device in which the number of check lines for detecting selection is only one, and data lines, address lines, and check lines can be pattern-wired on the back of a package.

[Means for solving problems]

FIG. 1 shows a principle block diagram of an electronic device equipped with a plurality of electronic circuit boards according to the present invention.

In FIG. 1, reference numeral 1 denotes a board selection device, which is connected to n electronic circuit boards via at/res wires 4. In FIG. The electronic circuit board is assigned an address by a switch or the like, and operates only when selected by an address signal from the selection means 1.

The electronic circuit board includes a constant current circuit 5 through which a predetermined current flows only when the board is selected by an address signal from the selection means 1, and the selection means 1 and the constant current circuit 5
are connected by one common line 6.

7 is a detection means for detecting the amount of current flowing through the common line 6, and when the detection value of this detection means 7 exceeds a predetermined value, a duplication display section 8 connected to the detection means 7 displays the duplication allocation.

(Function) If the number of electronic circuit boards selected by the board selection device 1 is one, the current value flowing through the common line 6 is always a predetermined value, but if two or more electronic circuit boards are selected due to duplicate allocation. Then, the current value flowing through the common vA6 is different from the predetermined value.

When the current value flowing through the common line 6 changes from the predetermined value, the current detecting means 7 drives the overlap display section 8 to display the overlap layout of the electronic circuit boards.

In the present invention, duplicate layout of electronic circuit boards can be determined using only one common line.

〔Example〕

FIG. 2 shows an embodiment of the present invention, which is an example of an electronic exchange, and the same parts as in the conventional circuit of FIG. 3 are given the same reference numerals.

In an electronic exchange, 20 to 30 electronic circuit boards (packages) 2 of the same specification are usually mounted in a shelf (box). In such an electronic exchange, the packages 2 are controlled in a time-sharing manner, and all the pancages 2 (for example, there are n pieces 11 to 11) are controlled from the device 1 corresponding to the board selection means
Using data lines 3 and address lines 4 connected to It has become. That is, the data is on data line 3.
The address signal flowing through the address line 4 is applied to a comparison circuit 9 provided in the package 2, and the address signal is distributed to all n packages 2 by the switch 9a as an address setting means. Only the package 2 whose address signal matches the address signal outputs a match signal 5YNC synchronized with the address signal, and the package 2 takes in data from the data line 3 based on this match signal 5fNC.

In the present invention, the coincidence signal line 9b to which the coincidence signal 5YNC of each package 2 is output is branched using a branch signal line 9C, and this is connected to the amplifier 51 of the constant current circuit 5.

The output of the amplifier 51 is connected to a transistor 53 via a resistor 52.
The emitter of the transistor 53 is grounded, and the collector is connected to a check terminal C provided on the package 2 via a load resistor 54.

The terminals C of each package 2 are connected by a check line 6 which is one common line. This check line 6 is connected to the power supply Vcc via a current-voltage conversion resistor 71 of a current detection means 7 installed in the selection device 1, for example.

Although the check line 6 is shown as a branch line on the circuit in FIG. 2, the check line 6 is formed on the printed circuit board and connected to the terminal C.
If the connection is made with a connector or the like, it can actually be formed using one common line. Furthermore, the current detection means 7 may be provided independently outside the selection device 1.

A voltage detector 72 is connected to both ends of the resistor 71 of the current detection means 7, and the output of the voltage detector 72 is connected to a comparator 73 to which a reference voltage Vr is applied. When the output value of the voltage detector 72 is below a predetermined value, the output of the comparator 73 does not change, but when the output value of the voltage detector 72 exceeds the predetermined value, the output of the comparator 73 changes. It is supposed to be done. That is, resistor 71, voltage detector 7
2 and a comparator 73 form a current detector 7 that determines whether the current value flowing through the check line 6 exceeds a predetermined value.

Also connected to the comparator 73 is a redundant display device 8 consisting of a buffer 71 for holding the output, a display 82 (equipped with a light source such as an LED, for example), and an alarm 83. When the output value of the comparator 73 changes when the output value of the comparator 72 exceeds a predetermined value, the display 82 lights up and the alarm 83 generates a warning sound.

The operation of the electronic device having a plurality of electronic circuit boards of the present invention configured as described above will be described next.

(1) When address assignment is normal, package 2 is
Only one of the packages 2, for example 12, is selected, and no other packages 2 are selected. At this time, a match signal 5YNC is output to the match signal line 9b of the 12 packages 2, and this signal 5YNC is input to the amplifier 51 of the constant current circuit 5 via the branch signal line 9c. Since the output of the amplifier 51 is input to the base of the transistor 53 via the resistor 52, the transistor 53 is turned on, and a current flows from the voltage [Vcc in the selection device 1 to the check line 6. Let I be the current that flows when the transistor of one package 2 is turned on, and let the value of the resistor 71 be R. Since 112 puff cages 2 are selected, a potential difference of R1 is generated across the resistor 71, and this is used for voltage detection. The voltage is detected by the device 72 as a voltage R1. Comparator 720 reference voltage Vr is RI<V
Since the value of r<2R1 is set, the output of the comparator 81 does not change and the overlap display device 8 does not operate.

(2) Address allocation error (overlapping) Two or more packages 2, for example, the packages 111 and 12, are selected in duplicate according to the address signal from the board selection device 1. At this time, the one-defeat signal 5YNC is output to the match signal line 9b of the two packages 2, II and 12, so the transistor 53 of the package 2, II and 12,
turns on at the same time. Then, the power supply Vcc in the selection device l
The current flowing from check wire 6 to only one package 2
This is about twice the current value I that flows when the switch is turned on. Therefore, a potential difference of 2RI occurs between both ends of the resistor 71, and this is detected by the voltage detector 72 as a voltage 2RI.

The reference voltage Vr of the comparator 72 is Rr < Vr < 2
Since the voltage Rr is set to the value Rr, the input voltage of the comparator 73 exceeds the reference voltage Vr, and the output of the comparator 73 changes. As a result, the redundant display device 8 is activated, the display 82 lights up in this embodiment, and the alarm 83 emits a warning sound.

In this way, the reference voltage Vr of the comparator 73 is R1<Vr
Since the value is set to <2RI, the overlap display device 8 does not operate when only one package 2 is selected by the board selection device 1, but the overlap display device 8 does not operate when at least two packages 2 are selected simultaneously by the board selection device 1. In such a case, the overlapping display device 8 is activated so that an abnormality in the substrate selection device 1 can be recognized.

In the above description, the switch 9a was used as a means of address assignment, but the means of address assignment is not limited to this, and a memory (RAM, ROM), etc. may also be used.

According to the device of the present invention, no matter how many packages 2 are connected to the board selection means or no matter how many of the n puff cages 2 are removed, the same one check line remains. 6 can be used to reliably detect duplicate allocation of package 2.

〔Effect of the invention〕

As explained above, according to the present invention, duplicate allocation of n packages can be detected by simply measuring the current value flowing through only one check line. This has the effect of being able to detect duplicate allocation of packages. Further, the electronic device including a plurality of electronic circuit boards of the present invention operates reliably no matter how many packages are connected to the board selection device, and is therefore extremely useful in practice.

[Brief explanation of the drawing]

FIG. 1 is a principle block diagram of an electronic device equipped with a plurality of electronic circuit boards according to the present invention, FIG. 2 is a circuit diagram showing an embodiment of the present invention, and FIG. 3 is a conventional electronic device using a 1/n detector. FIG. 4 is a circuit diagram of an electronic device including a plurality of electronic circuit boards, and is an explanatory diagram showing a connection between a conventional selection device and a package. DESCRIPTION OF SYMBOLS 1... Board selection means (device), 2... Electronic circuit board (package), 3... Data line, 4... Address line, 5... Constant current circuit,
6... Common line (check vA), 7... Current detection means, 8... Duplicate display section.

Claims (1)

[Claims] Selection means (1) for selecting one of the plurality of electronic circuit boards (2) according to an address signal, an address setting means (9a), and an address comparison circuit (9).
and a constant current circuit (5) through which a predetermined current flows when selected by the selection means (1) and operates; and the selection means (1) and the electronic circuit. one common line (6) connected to the constant current circuit (5) of the substrate (2); a detection means (7) for detecting the amount of current flowing through the common line (6); and the detection means (7). 1. An electronic device comprising a plurality of electronic circuit boards, comprising: a duplication display section (8) that displays duplication allocation according to a detected value of .