JPH04311123A - Device for allocating identification number - Google Patents

Abstract

PURPOSE:To automatically allocate identification(ID) numbers to plural devices cascade-connected through a serial data line independently of power ON to the devices. CONSTITUTION:An operation device 11 having a communication function and numerical controllers 12 to 15 are cascade-connected through the serial data line 16. Plural resistors R1 to R5 corresponding to the number of devices, having the same resistance value and mutually connected in series are connected to a constant voltage supplying circuit 18. Thereby the potential values of respective resistors are successively dropped from the maximum potential, i.e., the feed voltage of the circuit 18, in each certain voltage value and the voltage is finally reached to a reference potential. Thereby the ID numbers are allocated to the plural devices based upon the voltage impressed to both the terminals of each resistor and a potential difference between the potential of one end side of each terminal and a reference potential.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an identification number assigning device for assigning identification numbers to a plurality of devices having communication functions connected in series via a serial data line, and more particularly to an identification number assigning device for an FA system connected in series via a serial data line. A communication system consisting of a host computer, multiple numerical control devices, a PC, a robot control device, etc., a communication system consisting of a numerical control device, a control panel, an I/O device, etc., and multiple numerical control devices installed on the transfer line. This invention relates to an identification number assignment device for a numerical control device or the like.

0002

2. Description of the Related Art Generally, in order to communicate between a plurality of devices connected in series via a serial data line, an identification number is assigned to each device in advance, and each data packet sent and received via the serial data line is assigned an identification number. This identification number is added to clearly indicate the destination or source of each data.

Conventionally, in order to assign identification numbers to a plurality of numerical control devices connected in cascade via a serial data line,
An identification number is artificially determined for each device and the identification number is set in a storage device such as a rotary switch within each device. Alternatively, as shown in FIG. 4, the signal cable for requesting identification number assignment is sequentially connected from the device 2 at the end of the operating device 2 and the plurality of numerical control devices 3, 4, and 5 connected in cascade by the multi-drop serial data line 1. 6,7,
8, and the device that receives it stores the number plus 1 as its own identification number, and also transfers the numeric data of its own identification number to the next device. That's what I do. That is, for example, the operating device 2 stores the identification number 0 and transfers the numerical data 0 to the numerical control device 3. Therefore, the numerical control device 3 stores 1 as the identification number and transfers 1 to the next stage. In this way, each device is assigned an identification number.

0004

[Problem to be Solved by the Invention] However, in the former of the above-mentioned conventional identification number allocation techniques, the identification numbers are manually set in the storage device, so there is a possibility that incorrect settings may be made. . In addition, in the latter case, if any device on the serial data line is not powered on, the numerical data is not transferred to the subsequent device, making it impossible to assign an identification number to the subsequent device. There was a problem with becoming.

[0005] The present invention has been made in view of the above points, and it is an object of the present invention to automatically assign identification numbers to a plurality of devices connected in series via a serial data line, regardless of whether the devices are powered on. The purpose of the present invention is to provide an identification number assignment device that makes it possible to do this.

[0006]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides an identification number allocating device that allocates identification numbers to a plurality of devices having communication functions that are connected in series via a serial data line. a constant voltage supply means having a reference potential as the reference potential; a plurality of resistors having the same number as the plurality of devices, each having the same resistance value, and connected in series to the constant voltage supply means; a detection means for detecting the voltage across each of the resistors and the potential difference at one end of each of the resistors with respect to the reference potential; and an identification number assigned to the plurality of devices based on the voltage across each of the ends and the potential difference at one end detected by the detection means. An identification number allocating device is provided, characterized in that it has an allocating means for allocating an identification number.

[0007]

[Operation] A plurality of devices having communication functions are connected in series through a serial data line. A plurality of resistors, which are the same in number as the plurality of devices and have the same resistance value and are connected in series with each other, are connected to the constant voltage supply means. One end of the constant voltage supply means is connected to a reference potential (grounded). Therefore, the potential at each resistor decreases by the voltage value obtained by dividing the constant voltage supplied by the constant voltage supply means by the number of the plurality of devices, with the supply voltage of the constant voltage supply means being the highest potential. Finally, it reaches the reference potential. Focusing on this point, the assigning means assigns identification numbers to the plurality of devices based on the voltage across each resistor and the potential difference between one end of each resistor and a reference potential.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a communication system equipped with an identification number allocating device of the present invention. An operating device 11 and numerical control devices 12, 13, 14, 15 are connected in series by a multi-drop serial data line 16. The multi-drop serial data line 16 is a serial data communication line that allows each of the operating devices and numerical control devices to transmit and receive signals under the same conditions, no matter where on the line the operating devices and numerical control devices are connected.

On the other hand, the operating device 11 and the numerical control device 12
, 13, 14, 15, each built-in resistor R1, R2, R
3, R4, and R5 are connected in series via an assignment cable 17 and connected to a constant voltage power supply circuit 18, which is an external power supply. One terminal of the constant voltage power supply circuit 18 is grounded, and the other terminal outputs, for example, 24V. Resistor R1,
The resistance values of R2, R3, R4, and R5 are all the same value.

FIG. 2 is a diagram showing the internal configuration of the numerical control device 12. The numerical control devices 13, 14, and 15 also have exactly the same configuration. A driver/receiver (DV/RV) 23 is connected to the processor (CPU) 21 via a bus 22.
, axis control circuit (AXC) 24, RAM 25, ROM 26
, display control circuit (CRTC) 27, A/D converter 2
8 is connected. The driver/receiver 23 is connected to the multidrop serial data line 16 and the CPU 21
It operates as a buffer for packet communication between the controller 11 and other operating devices 11 and numerical control devices 13, 14, and 15. The axis control circuit 24 is connected to the servo motor 30 via the servo amplifier 29, and the axis control circuit 24 is connected to the processor 2.
Upon receiving the axis movement command from 1, the axis drive command is output to the servo amplifier 29. The servo amplifier 29 receives this drive command and drives the servo motor 30 of the shaft. A detected motor position value is fed back from the servo motor 30 to the axis control circuit 24 . A movable shaft of a machine tool 31 is mechanically connected to the servo motor 30. The RAM 25 stores various data, and the ROM 26 stores control programs and the like. The display control circuit 27 converts the digital signal into a display signal and outputs it to a display device 32 such as a CRT.

Input terminal 281 of A/D converter 28,
Both terminals of the resistor R2 are connected to 282, and the input terminal 281 is connected to the high voltage side 17a of the constant voltage power supply circuit 18 of the assignment cable 17, and the input terminal 282 is connected to the constant voltage power supply of the assignment cable 17. It is connected to the low voltage side 17b of the circuit 18. The input terminal 283 of the A/D converter 28 is connected to the ground terminal of the constant voltage power supply circuit 18 via the allocation cable 17. Input terminal 281,
The potential values V1, V2, and V3 input from 282 and 283 are converted into digital values by the A/D converter 28 and input to the processor 21.

The processor 21, driver/receiver 23, RAM 25, ROM 26, A/D converter 28
The operating device 11 is also equipped with a device corresponding to the above. FIG. 3 is a flowchart showing a procedure for assigning identification numbers to the operating device 11 and numerical control devices 12 to 15 connected in series to the multi-drop serial data line 16. This program is stored in the ROM (corresponding to ROM 26) of each device, and is executed by the processor (corresponding to processor 21) of each device when each device is initialized. In the following explanation, execution by the processor 21 of the numerical control device 12 will be explained as an example. The number following S indicates the step number.

[S1] Read out the preset supply voltage Vc (for example, 24 V) of the constant voltage power supply circuit 18. [S2] Input terminals 281, 28 of A/D converter 28
The potential values V1, V2, and V3 (for example, 0 V) inputted from No. 2,283 are read. [S3] Using the potential values V1 and V2 read in step S2, the voltage value Vr across the resistor R2 is calculated by the following formula. Vr=V1-V2 Note that the resistance R in other devices 11, 13, 14, 15
The voltage values at both ends of 1, R3, R4, and R5 are also the above-mentioned voltage value V.
It becomes the same value as r.

[S4] Using the potential values V1 and V3 read in step S2, calculate the potential difference Vn between the high potential end (17a) of the resistor R2 and the reference potential (ground potential) of the constant voltage power supply circuit 18 using the following formula. calculate. Vn=V1-V3 [S5] Using the voltage value Vc read in step S1 and the both-end voltage value Vr calculated in step S3, all the devices 11 to 15 connected in series to the multi-drop serial data line 16 are The number N is calculated using the following formula. N=Vc/Vr [S6] Voltage value Vc read in step S1 and voltage value Vr across resistor R2 calculated in steps S3 and S4
, and the potential difference Vn at the high potential end, the identification number n of the numerical control device 12 including the resistor R2 is calculated by the following equation. n=(Vc-Vn)/Vr [S7] The identification number n calculated in step S6 is stored in the RAM 25 as the identification number of the numerical control device 12.

Since identification numbers are assigned to the operating device 11 and the numerical control devices 12, 13, 14, and 15 in the manner described above, the assignment can be done automatically without manual intervention, and the identification numbers can be assigned to the operating device 11 and the numerical control devices 12, 13, 14, 15
Even if there is a device whose power is not turned on, it is possible to assign identification numbers to other devices other than the device whose power is not turned on without any problem. Moreover, when the power is turned on again to the device that has not been powered on, an identification number is automatically assigned to the device at the time of power on. Furthermore, calculating the total number N of the devices 11 to 15 connected in cascade is effective when monitoring the entire communication system or displaying the entire communication system on a display device.

In the above description, the processor and the A/D converter are connected to the operating device 11 and the numerical control devices 12 to 15.
Although the description has been made for a communication system in which one processor and one A/D converter are provided in the communication system, the above-mentioned identification numbers can also be assigned. Further, in the above explanation, the assignment of identification numbers to a communication system consisting of an operating device and a numerical control device has been explained. Communication system consisting of control device, PC, robot control device, etc., numerical control device, control panel, I/O
The present invention can be applied to communication systems consisting of devices, etc., as well as numerical control devices incorporating a plurality of numerical control devices on a transfer line.

[0017]

As explained above, in the present invention, the potential difference between the voltage across each resistor provided in each of a plurality of devices having a communication function connected in series through a serial data line and the reference potential at one end of each resistor is determined. Since identification numbers are assigned to multiple devices based on the above, it is possible to automatically assign identification numbers to multiple devices connected in cascade via a serial data line, regardless of whether the devices are powered on. It becomes possible.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a communication system equipped with an identification number allocation device of the present invention.

FIG. 2 is a diagram showing the internal configuration of a numerical control device.

FIG. 3 is a flowchart showing a procedure for assigning identification numbers to operating devices and numerical control devices.

FIG. 4 is a diagram illustrating number assignment of a conventional operating device and a plurality of numerical control devices connected in cascade via a multi-drop serial data line.

[Explanation of symbols]

11 Operating device 12, 13, 14, 15 Numerical control device 16 Multi-drop serial data line 17 Assignment cable 18 Constant voltage power supply circuit

Claims (5)

[Claims] 1. An identification number assignment device that assigns identification numbers to a plurality of devices having a communication function connected in series via a serial data line, comprising: constant voltage supply means with one end of the output set as a reference potential; a plurality of resistors, each having the same resistance value and connected in series to the constant voltage supply means, and the voltage across each of the resistors and the reference potential Identification characterized by having a detection means for detecting a potential difference on one end side, and an assignment means for assigning an identification number to the plurality of devices based on each both-end voltage and each one end side potential difference detected by the detection means. Numbering device. 2. The detection means and the allocation means are each provided in the same number as the plurality of devices, and each of the resistors, the detection means, and the allocation means are provided one each for each of the plurality of devices. The identification number allocating device according to claim 1. 3. The allocating means sets a constant voltage supplied by the constant voltage supplying means as Vc, a voltage across each end detected by the detecting means as Vr, and a potential difference between a high potential end of each of the resistors with respect to the reference potential. is Vn, the identification number n of the device to which the resistor corresponds is calculated by the following formula, and n
=(Vc - Vn)/Vr The identification number assignment device according to claim 1, wherein each identification number is assigned to the plurality of devices. 4. The identification number allocating device according to claim 1, wherein the allocating means further specifies the number of the plurality of devices based on the voltage across each terminal detected by the detecting means. 5. The allocation means determines the number N of the plurality of devices, where Vc is the constant voltage supplied by the constant voltage supply means, and Vr is the voltage across each end detected by the detection means.
5. The identification number allocating device according to claim 4, wherein N=Vc/Vr is calculated by the following formula: N=Vc/Vr.