JP2703368B2 - Test output device switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Industrial application field) The present invention is based on the number of output devices instead of a plurality of output devices that output the execution results of each output program of a test target system. The present invention relates to a test output device switching device for performing a test using a small number of test output devices.

Further, the present invention relates to a switching device for transferring data output to any of N addresses to n devices smaller than N.

(Prior Art) In a computer system to which a plurality of output devices are connected, usually, an output program designates a logical number (logical address) of an output device and makes an output request to an output control unit. On the other hand, the output control unit reads out the corresponding device number from the correspondence table of the logical number and the device number (physical address) of the output device, which is stored in advance. The output control unit performs an output required by the output program on the output device to which the read device number is assigned.

(Problems to be Solved by the Invention) In some cases, the output function of a computer system is tested using a smaller number of output devices than the number of output devices to be originally connected to the system. For example, there is a case where a test is performed on a system having five output devices in an operating state using two output devices for improvement or troubleshooting.

In such a case, an output test for an unconnected output device cannot be basically performed. If a test is to be performed on an unconnected output device, it is necessary to temporarily stop the test and reset the hardware for the output device to be tested.

However, in such a method, the test must be frequently interrupted, and the operation becomes extremely complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an output device switching device of a computer system capable of easily performing an output test.

Another object of the present invention is to provide an output device switching device that performs a test using a small number of output devices without interrupting the test and without being aware of the device number.

Still another object of the present invention is to provide an apparatus for transferring data output by designating a destination address to a smaller number of devices than the number of addresses.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, an output device switching device according to a first aspect of the present invention includes N (N is a positive integer) output devices connected to each other. Output program storage / execution means (10) for storing an output program of the test target system to be executed and executing the output program; and n connected to the test target system in place of the N output devices for testing. (N is a positive integer, n <N) test output devices (12a, 12b), and the correspondence between the N output devices specified by the output program and the n test output devices. Table means (14) for storing, and an output control means for selecting a test output device corresponding to the output device specified by the output program according to the contents of the table means, and outputting the contents according to the request of the output program ( 11) and Connectable device registration means (13) for storing correspondence data of the n test output devices which can be connected in advance, and associating any one of the n test output devices with an unconnected display device. Means (keyboard) for inputting a correction command for inputting the correction command, and when receiving the correction command from the input means, correspondence data of the test output device to be corresponded from the correction command is registered in the connectable device registration means. Rewriting means (15) for rewriting the correspondence of the test output device corresponding to the unconnected output device stored in the table means using the correspondence data.

According to a second aspect, in the configuration of the present invention, in order to correct the contents of the table means instead of the input means, data representing a switching order which changes as needed according to the use state of the test output device is stored. Storage order instructing means (26, 33), and rewriting means (25, 35) for rewriting the contents of the table means in accordance with the data representing the switching order stored in the switching order instructing means. .

According to a third aspect, the present invention provides a test output device that outputs a certain data until a certain period elapses.
Prohibiting means (31) for prohibiting the output device from outputting new data is provided.

(Operation) According to the configuration of the first aspect of the present invention, even when there is no test output device corresponding to the output device specified by the output program, the data output is performed by inputting the correspondence switching data from the input means. Becomes possible.

According to the configuration of the second aspect of the present invention, even when there is no test output device corresponding to the output device specified by the output program, the contents of the table means are automatically rewritten, and data can be output. .

According to the configuration of the third aspect of the present invention, the next output is not performed until a certain period elapses after one output device outputs one. Therefore, it is easy to check the output contents.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

First Embodiment FIG. 1 shows a test system 12 having two display devices (hereinafter, referred to as CRTs) and five CRs in a normal state.
An embodiment in which a test of a system 9 to be connected to T (hereinafter, referred to as a test target system) 9 will be described.

The storage / execution means 10 for storing the display programs 10a, 10b... Of the test target system 9 and executing the display programs 10a, 10b. The storage / execution unit 10 includes, for example, a memory that stores a plurality of display programs 10a and 10b, a CPU that executes the display programs 10a and 10b, and peripheral circuits such as a display unit. Two CRTs 12a and 12b are connected to the output control means 11 for testing. A device number (physical address) 70 is assigned to the CRT 12a. The device number 71 is assigned to the CRT 12b.
The device numbers assigned to the two test CRTs 12a and 12b are stored in a first device number table (connectable device registration means) 13.

The output control means 11 is connected to a second device number table 14. The second device number table 14 is a display program 10
The correspondence between the CRT logical number (CRT virtual address) specified by a, 10b... and the corresponding device number (CRT physical address) is stored. Second device number table
14 has 5 CRTs in the system under test,
It has five entries. Each entry stores a logical number designated by the display program and a corresponding device number. In this example, two CRTs 12a, 1
Only 2b is connected to the test target system 9. For this reason, in FIG. 1, the device number 70 is assigned to the logical number 1, the device number 71 is allocated to the logical number 3, and the logical numbers 2 and
4 and 5 are the device numbers 72 of dummy CRTs that do not actually exist.
Is assigned.

In order to switch and use the CRTs 12a and 12b, the switching means 15
The CRTs 12a and 12b are connected to the first and second device number tables 13 and 14.

 The operation of the system having the above configuration during a test will be described.

The display programs 10a, 10b,... Executed by the display program storing / executing means 10 edit the contents to be displayed, and specify the logical number of the output destination CRT to output a display request.
When the specified logical number is 1 or 3, the output control means 11 reads the device number 70 or 71 corresponding to the logical number from the device number table 14 and outputs the requested display content to the CRT of the device number. I do. Thus, the content according to the display program is displayed on the CRT.

A procedure when a display test corresponding to a logical number other than the logical numbers 1 and 3, for example, a logical number 5, is to be performed on the CRT 12a will be described.

The operator operates the switching key of the keyboard attached to the CRT 12a, and then inputs the numeral 5. As the switching key, for example, a tenth function key or the like can be used. The switching means 15 reads out the device number (= 70) assigned to the CRT 12a on which the keyboard is operated from the first device number table 13. The switching means 15 sets the read device number 70 to the second
Write to the area (fifth entry) for the logical number 5 in the device number table 14. Then, a software recovery process (usually clearing an abnormal sign) is performed on the device of the logical number 5 up to that time.

The switching means 15 writes the dummy device number 72 in the entry (first entry) for the logical number 1 corresponding to the device number 70. FIG. 2 shows the second device number table 14 thus rewritten. As a result of this rewriting, the display for logical number 1 is stopped, and the display for logical number 5 is stopped.
Made on CRT12a.

Similarly, when the operator designates the switched logical number from the keyboard, the CRTs 12a and 12b can be made to correspond to arbitrary logical numbers, and a display test corresponding to all logical numbers can be performed.

On the other hand, in a normal operation state, five CRTs are connected to the output control means 11, and the device numbers of the five CRTs are set in each entry of the second device number table 14. For this reason, in the normal state, there is a CRT corresponding to the logical number specified by the display programs 10a and 10b, and an arbitrary display is made there.

Next, specific configurations of the output control means 11 and the switching means 15 will be described with reference to FIG.

As shown in FIG. 3, signals (including commands, data, addresses, etc.) from the display program storage / execution means 10 are supplied to the I / O device 111. The I / O device 111 supplies the supplied signal to the data path 113 and the determination unit 115. The data path 113 includes, for example, a bus selector, a bus driver, a bus, and the like. The control unit 115 detects a display request signal among the signals supplied from the I / O device 111. Data path
113 responds to a control signal from the control unit 115, and
Is transmitted to the output terminal.

CRT drivers 117 to 125 for driving a CRT are connected to the first to fifth output terminals of the data path 113. In this embodiment, the first CRT driver 117 includes a test CRT 12a and a third CRT
The CRT 12b is connected to the driver 121.

The control unit 115 is connected to a reading unit 127 that reads the contents of the second device number table 14 under the control of the control unit 115.

The switching means 15 includes an I / O device 151, a control unit 153, and a write circuit 155. The I / O device 151 receives data from the keyboard and transmits the data to the control unit 153. The control unit 153
O receives the data from the O device 151 and receives the first device number table 13
And outputs a write control signal. The write circuit 155 controls the second device number table under the control of the control unit 153.
Rewrite the contents of 14.

The operation of the system shown in FIG. 3 will be described. For example, when the program 10a outputs a request to perform display on the CRT of logical number 1, this request is sent to the control unit 115 via the I / O device 111.
Supplied to In response to the display request, the control unit 115 controls the reading unit 127 to read the contents of the second device number table 14. The control unit 115 has a logical number 1 and a device number 70
, And outputs a control signal to the data path 113. The data path 113 passes display data and the like from the program 10a to the driver 117 in response to the control signal.

On the other hand, for example, if the display program 10b
, The control section 115 detects that the logical number 2 corresponds to the dummy device number 72. In this case, since the CRT corresponding to the logical number 2 does not exist (is not connected), the control unit 115
Is not controlled. The control unit 115 outputs an alarm to the operator, if necessary, to notify that an impossible display request has been made.

In this state, it is assumed that, for example, the operator instructs the switching of the display device and the logical number 2 from the keyboard of the CRT 12a. In this case, the control unit 153 controls the first device number table 13
From the CRT 12a is 70. Next, the control unit 153 writes the device number 70 in the second entry of the second device number table 14, and writes the device number 72 in the entry in which the device number 70 has been written. Control unit
115 checks the contents of the second device number table 14 again, so that the display of the display device of the logical number 2 is made on the CRT 12a.

In the above example, three display devices corresponding to the dummy device number 72 are not connected to the test target system. However, it can be easily performed without interrupting the display test on the unconnected display device.

In the above embodiment, the second device number table 14 was rewritten according to an input command from a keyboard attached to the CRTs 12a and 12b. However, as shown in FIG. 4, for example, an instruction to switch the display device from the system console 16 and a logical number and a device number of the display device may be input.

According to the first embodiment, even when the number of test display devices is smaller than the number of display devices to be originally connected to the test target system, a display test can be performed without interrupting the test.

According to the second embodiment and the first embodiment, the action of the operator is required to switch the display device. However, this method imposes a heavy burden on the operator. In the first embodiment, a CRT is used as a display device. However, the display device may be another display device such as a liquid crystal display device or a plasma display device. In addition, the present invention is not limited to the display test, and is applicable to various output function tests. Further, in the above embodiment, the number of display devices of the test target system is five and the number of display devices of the test system 12 is two, but the number of display devices is arbitrary.

Thus, the second embodiment provides a general system that can perform an output test while automatically switching the output device.

FIG. 5 shows the configuration of the second embodiment. The configuration in FIG.
In the normal state, the test target system to which the N output devices are connected is connected to n (n <N) output devices 22a for testing.
The case of testing using 2n is shown.

The test target system is a program storage and execution device 20,
The apparatus includes first and second device number tables 23 and 24, a switching unit 25, and a switching order table 26 indicating a switching order of output devices.

The program storage / execution device 20 stores the output contents in each output test of the test target system as output programs 20a and 20b.

A unique device number is assigned to each of the output devices 22a to 22n.

The first device number table (connectable device registration means) 23 stores the device numbers of the output devices 22a to 22n.

The second device number table 24 stores output programs 20a, 20b
The correspondence between the logical number (logical address) of the output device designated by (1) and the device number (physical address) of the actually connected output device 22a ... 22n is stored.

The output control means 21 receives an output request specifying the logical number of the output device from the output programs 20a, 20b,. The output control means 21 reads the device number corresponding to the specified logical number from the second device number table 24. Output control means
Reference numeral 21 outputs the content according to the instruction of the output program to the output device of the read device number.

The switching order table 26 stores data indicating a switching order that changes as needed according to the use state of the output device of the test output device in order to correct the contents of the second device number table 24. In the switching order table 26, for example, the switching order of the devices having the latest latest use time is set to 1, and the switching order of the devices having the latest latest use time is sequentially set to 2, 3,.

The switching means 25 rewrites the contents of the second device number table 24 in accordance with the switching order stored in the switching order table 26.

Next, the operation of the configuration shown in FIG. 5 will be described. The output control means 21 reads the contents of the second device number table 24 when there is an output request accompanied by designation of a logical number from the output program. If the device number corresponding to the specified logical number is the device number of the output device 22a ... 22n, the output control means 21
Supplies the output data from the output program to the output device assigned the device number.

When the output device of the device number corresponding to the logical number specified by the output program is undetermined (not connected), the device number corresponding to the specified logical number does not exist in the first device number table 23. In this case, the output control means 21 supplies a switching instruction signal to the switching means 25. The switching means 25 rewrites the second device number table 24 according to the switching order shown in the switching order table 26. Specifically, the switching means 25
Is stored in the corresponding entry of the second device number table 24 as the device number of the output device having the highest switching order, and stored in the first device number table 23 in the entry in which the device number has been stored up to that time. The dummy device number that has not been set is stored. The output control means 21 outputs the rewritten second
Output data is supplied to the output device according to the contents of the device number table 24.

Such an output device can be widely applied, for example, as a display device, a liquid crystal display device, a plasma display, etc., and as a printer, a typewriter, a line printer, a laser printer, a process I / O, or the like.

According to the above configuration, the output function of the test target system can be easily tested using a small number of output devices.

Next, a specific example of a device for switching the test output device according to the second embodiment will be described with reference to FIG. In this specific example, the display device is switched in the order of the latest display time, the output device is a CRT, N is 5, and n is 2.

In FIG. 6, the system to be tested is an output control means.
31; a program storage / execution unit 30; first and second device number tables 33 and 34;
A switching order table 36 is provided. The test system 32 includes two CRTs 32a and 32b for testing.

The program storage / execution means 30 stores the display programs 30a, 30b,... Of the test target system, and executes the storage program. Output control means 31 to program storage and execution means 30
Is connected. The output control means 31 has two CRs for testing.
T32a and 32b are connected. The CRT 32a is provided with a device number 70, and the CRT 32b is provided with a device number 71. CRT32a, 3
The device number 2b is stored in the first device number table 33.

The second device number table 34 includes display programs 30a, 30b,.
The correspondence between the logical number of the display device specified by the device number and the corresponding device number is stored. The second device number table 34 is
Corresponding to the number of CRTs of the system under test being five, five entries are provided. Each entry corresponds to a logical number. In this example, two CRs were used for testing.
Since only T32a and 32b are provided, device number 70 is assigned to logical number 1, device number 71 is assigned to logical number 3, and dummy numbers that are not actually connected are assigned to logical numbers 2, 4, and 5. It is assumed that the CRT device number 72 is assigned.

The switching order table 36 stores the latest time at which the CRTs 32a and 32b were used as data for designating the switching order of the test CRT.

The switching means 35 is connected to the output control means 31, the first and second device number tables 33 and 34, and the switching order table 36, and rewrites the contents of the second device number table 34.

 Next, the operation of the system shown in FIG. 6 will be described.

The program storage / executing means 30 is a display program 30a, 30
Execute b .. The display programs 30a, 30b,... Edit the contents to be displayed, and make a display request by designating the logical number of the output destination display device. The output control means 31 reads the device number corresponding to the designated logical number from the second device number table 34. The read device number is the first device number table
When it exists in 33, that is, when the designated logical number is 1 or 3, the output control means 31 transfers the display data to the CRT to which the read device number is attached. As a result, the C
The display contents according to the request of the display program are displayed on the RT. Further, the output control means 31 writes the time at that time in the area for the CRT in the switching order table.

When the display programs 30a and 30b output a display request by designating the logical numbers 2, 4, and 5, for example, the logical number 5, the output control means 31 refers to the second device number table 34 and It is detected that the number 72 corresponds. The device number 72 does not exist on the first device number table 33. For this reason, the output control means 31 outputs to the switching means 35 data indicating that the display device has been switched and the logical number 5 has been designated. In response to this data, the switching means 35 refers to the switching order table 36. The switching order table 36 stores the latest display time of each CRT. This refresh time is CRT32a, 3
It is updated every time it is displayed in 2b. In FIG. 6, the latest display time of the device number 70 is time1, and that of the device number 70 is time
It is stored as 2 (time1 is earlier in time than time2). Therefore, the switching means 35 extracts the device number (= 70) of the CRT having the oldest display time from the switching order table 36. The switching means 35 writes the extracted device number 70 in the area for the logical number 5 of the second device number table 34, that is, in the fifth entry. Further, the switching means 35 performs a soft recovery process (usually clearing an abnormal sign) on the device of the logical number 5 up to that time. Further, the dummy device number (72) is written in the entry for the logical number 1 in which the device number 70 has been set. According to the rewritten second device number table 34, the output control means 31
The display data of 30a, 30b is transferred to the CRT 32a. As a result,
The display for the logical number 1 device of the test target system is stopped, and the display for the logical number 5 is displayed on the CRT 32a. Further, the output control means 31 updates the latest display time of the device number 70 stored in the switching order table 36 to the display time time3. The contents of the second table 34 after rewriting are the same as in FIG. 2, and the contents of the switching order table 36 after rewriting are shown in FIG.

Hereinafter, each time the display program 30a, 30b specifies the logical number corresponding to the unconnected CRT, the contents of the second device number table 34 are automatically rewritten, and the display test is continued using the CRTs 32a, 32b. .

The specific configuration of the output control means 31 and the switching means 35 shown in FIG. 6 will be described with reference to FIG.

In FIG. 8, the output control means 31 includes an I / O device 311, a data path 313, a control unit 315, CRT drivers 317 to 325, a reading unit 327, and a timer 329 for counting the current time.

The switching unit 35 includes an I / O device 351, a control unit 353, and a write circuit 355.

The operation of each unit in FIG. 8 will be specifically described. When the display program 30a outputs a request to display on the display device of the logical cipher 1, the request is sent to the control unit via the I / O device 311.
315. In response to this display request, the control unit 315
Controls the reading unit 327 to read the device number 70 corresponding to the specified logical number from the second device table 34.
The control unit 315 controls the reading unit 327 to read the contents of the first device number table 33, and detects that the device number 70 is the number assigned to the CRT 32a connected for the test. The control unit 315 causes the data path 313 to supply the output data of the display program 30a to the driver 317. Next, the control unit 315 stores the current time indicated by the timer 329 in the switching order table 3.
Write to the entry for CRT32a in 6.

When the display program 30b outputs a request to perform display on the display device having the logical number 5, the control unit 315 refers to the second device number table 34 and detects that the logical number 2 corresponds to the device number 72. I do. The control unit 315 detects that the device number 72 does not exist in the first device number table 33. In response to this detection, the control unit 315 sends a switching signal and data indicating that the logical number 5 has been instructed to the I / O device 351. This data is supplied to the control unit 353 via the I / O device 351. Control unit 3
53 checks the contents of the switching order table 36 and finds that the latest use time is the oldest CRT (in this example, the latest use time is time1
The device number 70 of the CRT 32a). The control unit 353 controls the read / write circuit 355 to control the second device number table 34.
The device number 70 is written in the fifth entry, and the dummy device number 72 is written in the entry in which the device number has been written. The contents of the second device number table 34 after rewriting are the same as those shown in FIG.

The control unit 315 causes the data path 313 to transfer the display data for the display device with the logical number 5 to the CRT driver 317 in accordance with the contents of the rewritten second table 34. Thus, the display for the display device having the logical number 5 is made on the CRT 32a. Thereafter, the control unit 315 rewrites the rewriting order table 36 as shown in FIG. Thereafter, the same operation is repeated.

According to the second embodiment, even when the number of test output devices is smaller than the number of output devices that should be connected to the test target system, the output test can be executed without interruption.

In the second embodiment, the order of switching the output devices is the order of the latest display time. However, if the test output device is 3
If more than one unit is connected, a table for storing the correspondence between the number of times of switching and the device number may be provided, and the switching order may be determined by a combination of the latest display time and the switching circuit.

In an actual system, there are cases where it is not desirable to automatically switch the correspondence between the logical number and the device number. In this case, an exclusion sign may be added to the logical number and the device number. For example, when the CRT 32a is always used as the display device for the logical number 1, the device number 70 is written in the first entry of the second device number table 34, and for example, -1 is written in the first entry of the switching order table 36. Remember. The switching means 35 excludes the device number 70 from switching targets.

In the second embodiment, a new display may be made on a display device immediately after a certain display is made on the display device. However, this does not allow a sufficient check of the displayed contents. Therefore, if it takes a predetermined time to confirm the output result of the display device, the output control means 31
In addition, a delay function that does not switch the display content of the display device until a certain time has elapsed after the display is performed on the display device may be provided. For example, if the output control means 31
If it is determined that display is to be performed on T32a, the output control means 31
Is the current time and the device number stored in the switching order table 36
Compare with the refresh time of 70 CRTs. Output control means 31
Means that the difference between the current time and the latest display time is a fixed time, for example,
In the case of 5 seconds, 10 seconds or less, the display data is not supplied to the CRT 32a. Then, when the difference reaches a predetermined time, the output control means 31 supplies new display data to the CRT 32a to cause a new display.

In the first and second embodiments, the output control units 11 and 31, the switching units 15 and 35, the tables 13, 14, 33, 34, and 36 are constituted by individual components. However, in the present invention, these are
The configuration may be such that one microcomputer is used, and the function of each unit is executed by software. Therefore,
The operation of the microcomputer when the aforementioned delay function is added will be described with reference to the flowchart of FIG. In this case, the contents of each table are stored in the internal memory or the external memory of the microcomputer.

When there is an output request accompanied by designation of a logical number from the output program, the microcomputer executes the process shown in FIG. First, the content of the designated logical number is read (step S1). Next, it is checked whether the device number corresponding to the read logical number is normal (70 or 71) or abnormal (72) (step S2). When the device number corresponding to the specified logical number is normal, the difference between the latest use time and the current time to which the device number is assigned is obtained. Until the difference reaches a certain time, the process is in a delay state (steps S3, S8). When this difference reaches a certain time,
The display data is supplied to the CRT, and the display is performed (step S4). After that, the latest use time of the CRT is updated.

On the other hand, if it is determined in step S2 that the device number is abnormal, the device number of the CRT whose latest use time is the oldest is searched (step S6). The device number of the CRT whose latest use time obtained in step S6 is the oldest is written in the entry corresponding to the logical number obtained in step S1 of the second device number table, and the device number is previously written. A dummy device number is written in the entry that was entered. Thereafter, control proceeds to step S3.

In the above embodiment, the test target system was tested by connecting the test output device to the test target system. However, for example, the program storage / execution units 10, 20, 30 of the first and second embodiments are part of the test system, and the display program of the system to be tested is loaded into the program storage / execution units 10, 20, 30. By executing the program, the function of the output program can be checked with a small number of output devices.

In the above embodiment, the first and second device number tables, the switching order table, the switching means, and the like are added to the test target system. Even if these elements or functions are added to the system under test in advance for the test,
Alternatively, it may be added to the test target system at the test stage.

In the above embodiment, the test output device switching device has been described. The present invention is not limited to the above embodiment. INDUSTRIAL APPLICABILITY The present invention can be widely applied to a system in which data supplied by designating N (5 in the embodiment) addresses is supplied to n (2 in the embodiment) devices smaller than N while switching the devices. It is.

[Effects of the Invention] According to the present invention, a test can be performed efficiently even when the number of test output devices is much smaller than the number of output devices to be connected to the test target system.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is a diagram showing the contents of a second device number table after rewriting,
3 is a block diagram for specifically explaining the configuration of FIG. 1, FIG. 4 is a block diagram showing a modification of the configuration shown in FIG. 1, and FIG. 5 is a second embodiment of the present invention. FIG. 6 is a block diagram for specifically explaining the configuration of FIG. 5, FIG. 7 is a diagram showing the contents of the switching order table after rewriting, and FIG. 8 is a diagram shown in FIG. FIG. 9 is a block diagram showing the details of the configuration, and FIG. 9 is a flowchart for explaining another embodiment of the present invention. 10a, 10b, 30a, 30b ... display program, 11, 21, 31 ... output control means, 12a, 12b, 32a, 32b ... CRT, 13, 14, 23, 24, 26, 33, 34, 36 ... ... Table, 15,25,35 ... Switching means.

Claims (3)

(57) [Claims] 1. An output program storage / execution means for storing an output program of a test target system to which N (N is a positive integer) output devices are connected in an operating state, and executing the output program; Therefore, instead of N output devices, n (n is a positive integer, n <N) test output devices connected to the test target system, and N output devices specified by the output program Table means for storing the correspondence between the device and the n test output devices; and selecting a test output device corresponding to the output device specified by the output program according to the contents of the table means;
Output control means for outputting the contents according to the request of the output program, connectable device registration means for storing the device numbers of the n test output devices which can be connected in advance, and an output to which the output program is not connected Input means for inputting a correction command for associating any of the n test output devices when the device is designated; and when the correction command is received from the input means, the correction command should be applied by the correction command. When the device number of the test output device is registered in the connectable device registration means, the correspondence relationship of the test output device corresponding to the unconnected output device stored in the table means using this device number. And a rewriting means for rewriting the test system, wherein the system under test to which the N output devices are connected in the operating state is tested using the n test output devices. Output device switching device for testing. 2. An output program storage / execution means for storing an output program of a test target system to which N (N is a positive integer) output devices are connected in an operating state, and executing the output program; Therefore, instead of N output devices, n (n is a positive integer, n <N) test output devices connected to the test target system, and N output devices specified by the output program Table means for storing the correspondence between the device and the n test output devices; and selecting a test output device corresponding to the output device specified by the output program according to the contents of the table means;
Output control means for outputting the contents according to the request of the output program, connectable device registration means for storing the device numbers of the n test output devices which can be connected in advance, and an output to which the output program is not connected When a device is designated, in order to make any one of the n test output devices correspond, a switch that updates and stores data representing a switching order that changes at any time according to the use state of the n test output devices. An order instructing means, when the output device specified by the output program is determined to be unconnected to the test output device from the contents of the table means and the registered contents of the connectable device registering means, The contents of the table means are rewritten according to the data representing the switching order stored in the output program, and one of the test output devices is connected to the output device specified by the output program. Is thereby provided with rewriting means, a test output device switching device for the system under test are N output device is connected to the test with n-number of test output device in the operating state. 3. An output program storage and execution means for storing an output program of a test target system to which N (N is a positive integer) output devices are connected in an operating state, and executing the output program; Therefore, instead of N output devices, n (n is a positive integer, n <N) test output devices connected to the test target system, and N output devices specified by the output program Table means for storing the correspondence between the apparatus and the n test output devices; connectable device registration means for storing the device numbers of the n test output devices which can be connected in advance; The output device to be connected to any one of the n test output devices while referring to the contents of the table means and the registered contents of the connectable device registration means. Means for outputting the contents requested by the device, and prohibition means for prohibiting the test output device from outputting new output data until a certain period of time has elapsed after outputting the output data from a certain test output device. A test output device switching device for testing a test target system to which N output devices are connected in an operating state by using n output devices.