JP2847887B2 - Programmable scanner - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a programmable scanner, and more particularly, to an improvement in expansion of a selected channel.

<Prior Art> In general, a scanner is used for channel switching in multipoint measurement.

By the way, the number of channels in one conventional scanner is equal to the number of channels of a switching element such as a relay mounted on one scanner card and the number of input terminals.
It was limited by the number of scanner cards installed in one scanner.

Specifically, the number of channels mounted on one scanner card is 10 to 20 channels, the number of scanner cards mounted on one scanner is about 10, and the maximum number of channels of one scanner Had about 200 channels.

Therefore, for example, when measuring 300 channels, 2
Two scanners capable of selecting the 00 channel are used, and these two scanners are controlled by a controller such as a personal computer via a communication interface.

<Problems to be Solved by the Invention> However, according to such a conventional configuration, a controller such as a personal computer is required, and programming for operating the controller in a desired sequence is also required. Get higher.

The present invention pays attention to such a point, and an object of the present invention is to provide a programmable scanner that can easily add channels with a relatively simple configuration.

<Means for Solving the Problems> A programmable scanner according to the present invention is a programmable scanner in which a plurality of cascadable units can be connected, and each programmable scanner has a plurality of switching units in which one or a plurality of units are selectively driven. An input terminal to which a switching start signal is input from the outside, a switching control circuit that starts drive control of these switching elements according to the switching start signal, and outputs a switching end signal when a series of switching is completed; And an output terminal for outputting a switching end signal, wherein the switching end signal of the preceding programmable scanner is input to the subsequent programmable scanner as a switching start signal.

<Operation> The switching control circuit controls the driving of the plurality of switching elements by inputting the switching start signal, and outputs a switching end signal to the outside when a series of switching ends.

Here, the switching end signal output to the outside is:
It can be input as a switching start signal to another programmable scanner having the same configuration. That is, by cascading a plurality of programmable scanners using the switching start signal and the switching end signal as synchronization signals, the time relationship between these programmable scanners can be controlled.

Thus, the number of channels can be expanded with a simple configuration in which a plurality of program scanners are connected in cascade without using a conventional controller.

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

FIG. 1 is a block diagram showing one embodiment of the present invention. In the figure, a first terminal 1 corresponding to a plurality of n channels is connected to a common second terminal 4 via a plurality of n switching elements 3 mounted on a scanner card 2. In addition, as the switching element 3, a relay, a semiconductor switch, or the like is used. The connection of the switching element 3 is controlled by a switching control circuit 5. As the switching control circuit 5, for example, a microprocessor is used. The switching control circuit 5 includes a ROM 6 in which a control program is stored, a RAM 7 in which switching control data of the switching element 3 is stored, a keyboard 8 for setting switching control data of the switching element 3, and switching of the set switching element 3. A display 9 for displaying control data; an external storage device 10 such as an IC card for storing a switching control sequence of the switching element 3; a communication interface 11 for controlling the GP-IB
Etc. are connected. Switching control circuit 5
An output terminal 12 for outputting a switching signal RDY every time each switching element 3 is switched, and a switching start signal STA from the outside.
An input terminal 13 to which RT is input and an output terminal 14 that outputs a switching end signal END when a series of switching ends are connected.

FIG. 2 is an explanatory view showing an example of use of the programmable scanner configured as shown in FIG. 1. Measurement is performed by combining three programmable scanners having a plurality of n-channel first terminals and one measuring device. 1 shows an example of a system. The programmable scanner 15 is used as a master scanner, and an output terminal of a switching end signal END is connected to an input terminal of a switching start signal START of a programmable scanner 16 used as a slave scanner. The output terminal is connected to the input terminal of the switching start signal STRAT of the programmable scanner 17 used as a slave scanner. The output terminal of the switching signal RDY of each of the programmable scanners 15 to 17 is connected to the input terminal of the trigger signal TRG of the digital multimeter 18 used as a measuring instrument, and the output terminal O of the measurement signal is output.
The UT (second terminal) is connected to the input terminal IN of the digital multimeter 18 for measuring signals. That is, the three programmable scanners 15 to 17 receive the switching start signal STAR.
T and the switching end signal END are cascaded as synchronization signals, and are connected in parallel to the digital multimeter 18.

FIG. 3 is a state transition diagram of the master programmable scanner, and FIG. 4 is a state transition diagram of the slave programmable scanner. Both become idle when the power is turned on. Then, the master programmable scanner enters a scan state when a start command is applied from a keyboard or communication in an idle state or a scan interval signal is generated inside the switching control circuit, and switching ends after sequentially switching the n-channel switching elements. Outputs the signal END and enters the idle state. On the other hand, the slave programmable scanner is in an idle state, and enters a scanning state when a switching end signal END is applied to the switching start signal START from the master programmable scanner or the slave programmable scanner in the preceding stage, and switches after sequentially switching the n-channel switching elements. End signal EN
Outputs D to enter the idle state.

FIG. 5 is a timing chart for explaining a part of the operation of the measurement system of FIG. Programmable scanner
Reference numeral 15 denotes (b) to (b) when the scan interval signal shown in (a) is generated inside the switching control circuit 5.
As shown in (d), switching of the switching elements 3 from the first channel CH1 to the n-th channel is started. The switching order of the switching elements 3 can be set arbitrarily by the switching control circuit 5. Then, when a series of switching is completed, a switching end signal END is output to the next-stage programmable scanner 16 as a switching start signal START as shown in (e).
The programmable scanner 16 starts switching the switching elements 3 from the first channel CH1 to the n-th channel as shown in (f) to (h). The switching order of the switching elements 3 can be arbitrarily set by the switching control circuit 5. Then, when a series of switching is completed, a switching completion signal similar to (e) is output.
END is output to the next-stage programmable scanner 16 as a switching start signal START, which is not shown. On the other hand, every time the switching element 3 is switched, a switching signal RDY shown in (i) is sent to the digital multimeter 18 as a trigger signal T.
Entered as RG. The digital multimeter 18 performs measurement on the measurement signal input via each switching element 3 at the timing shown in (j) according to the trigger signal TRG.

With this configuration, a plurality of programmable scanners can be connected in cascade with the switching start signal and the switching end signal as synchronization signals, and the time relationship between these programmable scanners can be controlled. The number of channels can be expanded with a simple configuration that simply connects multiple program scanners in cascade.

In addition, the controller function of the master programmable scanner can be simplified by managing the scan interval cycle in consideration of the number of scan channels of the cascade-connected slave programmable scanners.

Further, since the switching control of each programmable scanner is independent for each programmable scanner, the degree of freedom for each programmable scanner is increased.

Further, in the above-described embodiment, an example has been described in which an arbitrary one-channel measurement signal is selected from a plurality of channels of measurement signals and output to a measuring instrument. This is also effective when outputting to a channel.

By the way, in the embodiment of FIG. 1, an example is described in which a multiplexer card for selectively switching and driving a plurality of switching elements one by one in time series is mounted as a scanner card, but as shown in FIG. a plurality of switching elements SW ₁₁ to SW ₄₄ is also effective to scanners connected matrix card is mounted in a matrix. In this case, for example, the row terminal iT ₁ ~iT ₄ Connect the measurement object (DUT) 19, the column terminal jT ₁ ~jT ₄ connecting the measuring device 20, 21 and generator 22.

With this configuration, you are possible to perform various measurements and controls driving of the plurality of switching elements SW ₁₁ to SW ₄₄ at the same time.

Although FIG. 6 shows an example in which each intersection is constituted by one switching element, it is also possible to multiplex with a plurality of systems according to the application.

FIG. 7 is an explanatory view showing the cascade connection of the programmable scanners 24 to 26 on which the matrix card as shown in FIG. 6 is mounted as in FIG. 2, and FIG. 8 explains a part of the operation of FIG. FIG. Programmable scanner 24, by scanning interval signal shown therein in (a) is generated, starts the switching of the switching element SW ₁₁ to SW ₄₄ as shown in (b) ~ (d). Combinations of selection of the switching elements SW ₁₁ to SW ₄₄ can be arbitrarily set. Then, the programmable scanner 24 synchronizes with the falling edge of the scan interval signal and switches the switching end signal END as shown in FIG.
Is output to the next-stage programmable scanner 25 as the switching start signal STRAT. Programmable scanner 25
Is the switching element SW ₁₁ as shown in (f) to (h).
To start the switching of ~SW _44. It is also arbitrarily set combination of these selection switching elements SW ₁₁ to SW _44. The programmable scanner 25 receives the switching start signal STRA from the preceding programmable scanner 24.
As shown in (i), the switching end signal is synchronized with the rising edge of the switching end signal END applied as T.
END is output to the next-stage programmable scanner 26 as a switching start signal START.

According to the system configuration as shown in FIG. 7, it is possible to cascadely connect a plurality of programmable scanners by using the switching start signal and the switching end signal as synchronization signals as in FIG. 2, and to control the time relationship between these programmable scanners. The number of channels can be expanded with a simple configuration in which a plurality of program scanners are connected in cascade without using a conventional controller.

<Effects of the Invention> As described above, according to the present invention, a programmable scanner that can easily add channels with a relatively simple configuration can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing an example of use of a programmable scanner configured as shown in FIG. 1, FIG. 3 is a state transition diagram of a master programmable scanner, FIG. 4 is a state transition diagram of the slave programmable scanner, FIG. 5 is a timing chart for explaining a part of the operation of the measurement system of FIG. 2, FIG. 6 is a block diagram showing another embodiment of the present invention, and FIG. FIG. 7 is an explanatory view showing an example of use of the programmable scanner of FIG. 6, and FIG. 8 is a timing chart for explaining a part of the operation of the measuring system of FIG. 1,4 ... iT, jT ... terminal, 3, SW ... switching element, 5
... Switching control circuit.

Claims (1)

(57) [Claims] A plurality of cascadable programmable scanners, each of which includes one or more selectively driven switching elements, and a switching start signal input from outside. A switching control circuit that starts driving control of these switching elements in accordance with the switching start signal and outputs a switching end signal when a series of switching ends, and an output terminal that outputs a switching end signal to the outside. A programmable scanner, characterized in that a switching end signal of a preceding programmable scanner is input to a subsequent programmable scanner as a switching start signal.