JPH01297754A - Interface system - Google Patents

Abstract

PURPOSE:To detect the excess connection of an interface by subtracting a null address sequentially by the subtracter of an interface device when a main body device sends the null address not being indicated by the interface device, and transmitting a detecting signal to the discriminator of a main body. CONSTITUTION:When an interface unit 3 in a basic part is indicated, the value of a rack select signal is subtracted sequentially by the subtracter 5 of each additional interface starting from the subtracter of the interface unit of the basic part. For example, when an eighth additional unit 20-8 is connected exceeding a regulated number, an input/output processor 2 outputs the rack select signal of 0 similarly, and the rack select signal 0 is detected by the detecting circuit 5B of the additional interface unit 20-8, and a 0 detecting signal is outputted to a rack over information line 13, thereby, the input/output processor 2 recognizes that the connection of the additional interface units exceeding the regulated number is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an interface system for connecting a plurality of interface devices to a common lot.

(Prior Art) FIG. 3 shows the configuration of a system for connecting a plurality of interface devices (units), which has been widely used in the past.

In FIG. 3, 1 is a processor unit, which includes a basic section 110 units 1 to 3 and an interface (T10
) Units l-5-1 to l-5-2 are alternatively selected and information is communicated with external equipment via the selected interface unit.

In order to select an interface, rack select lines 1 to 4-1 to 4-n are connected between the basic interface units 1 to 1, the first to n-th interface units 5-1 to 5-n, and the processor unit 1. is set up.

The output processor 2 is provided in the processor unit 4, and the output processor 2 connects No. 13, which designates the interface unit, to the rack cell I/receiver 1 and lines 4-1 to 4-n to the address generator 2.
-1 causes the selected interface unit to become operational. Selected JAlso transferred from the interface unit)
i! The i-report is sent to the human output block 2 via a lotus (not shown).

Here, the first to nth interface units are added interface units.

For example, when adding seven interface units, eight rack select lines 1 to F1 are required, and as the number of additional interface units increases, rack select lines 1 to F1. Is Q also J Soyasa? There was a drawback that it didn't work. In order to solve this drawback, the next proposed interface unit connection method (second conventional example) is shown in FIG.

In FIG. 4, parts similar to those in the first conventional example shown in FIG. 3 are designated by the same reference numerals.

The second conventional example is an example in which the rack select wires 1 and 4 are connected by a common lot, and an identification number is assigned to the interface unit 1 in advance, and for example, three rack select wires are connected to three rack select wires (not shown in the figure). By supplying a rack select signal indicating the identification number to the input/output processor 2, the expansion interface unit indicated by the identification number is selected.

On the other hand, on the expansion interface unit 1-5 side, a comparator 5B is installed, which is not shown in FIG. There is. Compare the identification number set by the setting switch and the rack select line with the identification number indicated by the comparator 5B, and when the identification numbers match, the comparator 5B indicates that this interface unit 1- has been selected. A match signal is output to the control circuit 5C of the interface unit as a select 1 signal indicating an operable state.

In this second conventional example, the main line of the rack select line 4 does not have to be increased even if the number of expansion interface units 1 to 1 is increased, which may be an advantage.
8 to set number +j, operator or setting step 5
The drawback is that the interface unit's identification number cannot be set by operating the 8.

In order to solve this drawback, the configuration of improved interface units 1 to 1 is shown in FIG.

In FIG. 6, the expansion interface units 1 to 5 are connected to the next i! ! ! A subtracter 5AA is provided between the expansion interface unit 1 and (not shown) which subtracts the input signal by 1''' and outputs the subtractor 5AA. °゛0°
0'53B is provided to detect that it is the helper I2.

When the human output processor 2 supplies the identification number to be selected as a 3-bit signal to the rack select line, this signal is sequentially subtracted by the subtracter 5AA of each unit and becomes 0'' in the target unit. Therefore, which interface unit selects the interface unit that detects this 0°' signal or the input/output processor?

This connection method makes it possible to eliminate the drawback of setting an identification number by the operator.

(Problem to be solved by the invention) In the interface system according to the second conventional example, the number of interface units that can be expanded is determined by the number of rack signal lines. If the number of rack signal lines is increased in order to enable expansion, there is a problem that needs to be resolved when more than the specified number of expansion units are connected. Let me briefly explain the points.

For example, if the rack signal lines are 10-tree, the number of interface units that can be added is extremely large, such as 210. Therefore, when it is desired to add an interface unit, the operator must visually divide the existing interface unit, which is a cumbersome task, if the interface unit shown in FIG. 6 is used.

SUMMARY OF THE INVENTION An object of the present invention is to solve the two problems and provide an interface system that can automatically detect that more than a specified number of interface devices are connected.

[Means to solve the problem]

In order to achieve such an object, the present invention transmits an address for selectively specifying a plurality of interface devices from an address generator of the main device to the serially connected interface devices via a signal line. , wherein each of the interface devices includes a subtracter that subtracts the input address and outputs the subtracted address to the next stage interface device, and the input address before subtraction by the subtracter is a predetermined address. and an address detector that sends a detection signal to the main unit when detected, and when a specific address is output from the main unit GJ or the address generator, the address detector outputs the detection signal from any of the plurality of interface devices. The present invention is characterized in that it includes a discriminator that determines that a predetermined number or more of the interface devices are connected when a detection signal is received.

(Function) In the tree invention, an empty address that does not specify an interface device is provided as a specific address, and when an empty address is sent from the main device, this empty address is processed by the subtracter of the interface device. Subtracted sequentially. When any of the detectors of the interface device sends a detection signal as a response to the discriminator of the main device, the number of interface devices connected exceeds the predetermined number that can be connected. can automatically detect over-connection of an interface by receiving the detection signal.

〔Example〕

Hereinafter, embodiments of the wooden invention will be described in detail with reference to the drawings.

FIG. 1 shows the basic configuration of an embodiment of the present invention.

In the tree embodiment, the signal line 13 for transmitting a signal notifying the rack over notification is connected to one end of the discriminator 2-2 of the turnout processor 2 in the system configuration of the second conventional example shown in FIG. Each expansion unit l-20-1 to 20-7 outputs a signal indicating that it has detected that the rack select signal is °°0°° to the rack over notification line 13 in the form of a level H"' signal. I try to do that.

Also, as an identification number for selecting each expansion unit, the basic part ■10 is set to 0°°, the first expansion interface unit 20-1 is set to ``1'', and the seventh expansion interface unit 20-7 is set to ``7''. '', and the interface unit is selected by the three-hit rack select signal.

t2 Oh, the basic interface unit is not connected to the rack over notification line.

Therefore, it becomes 0°' or an empty address when checking the interface connection.

In addition, the pedestrian processor is provided with a discriminator 2-1 that determines that a predetermined number or more of expansion interface units are connected when it detects that a level "H" signal is generated on the rack over blood line. Note that this discriminator may be a known signal level discriminator using a comparator or the like.

FIG. 2 shows the circuit configuration of the additional interface unit according to the embodiment of the present invention.

In Figure 2, the expansion interface unit]・20
Inside is a 'fA calculator 5AA similar to the conventional example shown in FIG.
A "0" detection circuit 53B is provided, and "0" detection circuit 53B is provided.
``In the detection circuit 58B, whether the rack select signal is 0'
'', a detection signal of ``0'' is outputted to the control circuit 5C and also to the tick-over notification line 13 without indicating that fact.

Returning to FIG. 1, the operation of this embodiment will now be explained.

When the rack select signal "o" is output from the human output processor 2 at the initial time of power-on, when the basic interface unit l~3 is specified, each extension starts from the subtracter of the basic interface unit i~. Interface unit subtractor 5AA
Relax select 1-signal value is 0 → 7-6...→
1 and are sequentially subtracted. Here, if the number of connected extension interface units 20 is within the specified range, the extension interface units l-20-1 to 20-7 do not detect the rack select signal "°0'°, so the rack over notification line 13 is a “0” detection signal or not generated.

Next, for example, if the number of eighth expansion units 20-8 exceeds the specified number, and the crowd processor 2 similarly outputs a rack select signal of '0'', the rack select signal is Since it is 0'° at the time of input to the expansion unit 20-8, the expansion interface unit l-20
-8 0 detection circuit 58B rack select 1- signal ``0'
” is detected, and an o detection signal is output to the rack over notification line 13. By inputting this "0°" detection signal, the turnout processor 2 can determine whether the number of additional interface units is exceeded.

On the other hand, during normal system operation with a regular number of expansion interface units connected, the crowd processor 2 outputs a signal of, for example, 1° as a rack select signal.
When outputting , the first expansion interface unit 2
0-1 '0°' detection (rack over notification line 13 for No. K)
Output to. Therefore, in the present invention, the people flow processor 2 can know that the selection of the additional interface unit is reliably performed by receiving this "0'" detection signal. Another advantage is that it is possible to know the failure of the expansion interface unit by not generating the °' detection signal.

Next, regarding the application form of this embodiment, the following can be considered.

1) In this embodiment, the basic part interface unit 3 and the rack over notification line are not connected, or if it is desired to confirm the selection of the basic part interface unit, the basic part interface unit 3 is connected to the rack over notification line.

However, the identification numbers for the interface units should be changed sequentially from basic interface unit 3 to ゛°1°°.
,゛2°.

..., and leave the identification number ``0°'' as an empty address in order to detect a rack over.

[Effects of the Invention] As explained above, according to the present invention, an empty address that does not specify an interface device is set as a specific address, and when an empty address is sent from the main unit, this empty address are sequentially subtracted by the subtractor of the interface device. When any of the detectors in the interface device sends a detection signal as a response to the discriminator in the main device, the number of devices that can be connected exceeds the predetermined number.
Since the interface device is connected, the discriminator receives the detection signal to automatically detect excessive connection of the interface.

Furthermore, the present invention has the advantage that the conventional subtractive interface device system does not need to be significantly modified in order to implement the new function of checking excess connections of the interface device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of an embodiment of the present invention, FIG. 2 is a circuit diagram showing the configuration of an interface unit of the embodiment of the present invention, and FIG. 3 is a block diagram showing the system configuration of the first conventional example. , Fig. 4 is a block diagram showing the system configuration of the second conventional example, and Fig. 5 shows the expansion interface units 1 to 1 shown in Fig. 4.
FIG. 6 is a circuit diagram showing another configuration of the expansion interface unit shown in FIG. 4. DESCRIPTION OF SYMBOLS 1... Processor unit, 2... Output processor, 3... Basic section 110 unit 1, 4... Rack select line, 5.20... Expansion interface (Ilo) unit, 58 ...Setting switch, 5B...Comparator, 5C...Control circuit, 588...Subtractor, 5[]B...0 detection circuit, 13...Rack over notification line. 2nd A. Expansion of the 4th generation of the most pressing example A. >'77 6th 7th Ace Unit Box Map

Claims (1)

[Scope of Claims] 1) An interface system in which an address for selectively specifying a plurality of interface devices is sent from an address generator of a main unit to the serially connected interface devices via a signal line. , each of the interface devices includes a subtracter that subtracts the input address and outputs it to the next stage interface device; and when the subtracter detects that the input address before subtraction is a predetermined address, it outputs a detection signal. and an address detector that sends the output to the main body device, and the main body device receives the detection signal from any of the plurality of interface devices when the address generator outputs a specific address. An interface system comprising: a discriminator that determines that a predetermined number or more of the interface devices are connected.