JPH1145105A - Backup system for data for cnc device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data backup system for CNC device with which the dynamic data of high frequency can be backed up without using any external storage medium and auxiliary power source and data can be restored without erasing them because of an operation error. SOLUTION: When ordinarily operating a CNC device 1 in the data management of the CNC device 1, the dynamic data of the high reloading frequency stored in a volatile memory (SRAM 3) are backed up. In this case, when a voltage is lowered, the stored contents in the volatile memory (SRAM 3) are automatically written in a writable non-volatile memory (FROM 7) so that the data can be backed up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CNC device and, more particularly, to a data backup for storing frequently rewritten data in a CNC device.

[0002]

2. Description of the Related Art Data handled by a CNC device includes static data with a low frequency of rewriting such as programs and system parameters, and dynamic data with a high frequency of rewriting such as position data. A conventional CNC device stores static data with a low rewriting frequency in a FROM (flash RO).
M) and the like, and dynamic data that is frequently rewritten is stored in a volatile memory such as an SRAM (static RAM).

[0003] Volatile memory such as SRAM is used for reading / writing.
It is excellent in the degree of freedom of writing, but has the disadvantage that the contents of the memory are lost when the main power of the device is turned off because of the volatility. For this reason, in the conventional CNC device,
An auxiliary power supply is connected to the SRAM to perform battery backup, thereby retaining stored contents.

[0004]

In the storage means used in the CNC device, the FROM does not require an auxiliary power supply, but the number of times of writing is limited, so that dynamic data that is changed in ms units as in the CNC device is limited. Is not appropriate when dealing with In addition, although the SRAM has no limitation on the number of times of writing and is easy to rewrite data, it requires an auxiliary power supply, and is subject to an accident such as a voltage drop due to deterioration of the auxiliary power supply, a failure of the auxiliary power supply circuit, or a drop of the auxiliary power supply. The stored contents may be lost.

[0005] In order to prevent such a data loss accident caused by the auxiliary power supply, there is known a configuration in which stored contents are stored in another storage medium such as a memory card. FIG. 4 is a diagram for explaining data backup of a CNC device provided with another storage medium. In FIG. 4, the CNC device 1 includes:
CNC device main body 2, SRAM 3 for storing dynamic data such as position data that is frequently rewritten, and SRAM 3
Auxiliary power supply 4 and power supply device 5 for driving CNC device 1
And an external memory 10 such as a memory card for backing up the storage contents of the SRAM 3. However, there is a problem in that storing data in a storage medium provided separately from the SRAM requires a data saving operation.

Further, in a case where it is difficult to turn on the power due to a failure of the CNC device, if the backup of the data is neglected, it is difficult to restore the data from the CNC device, and it is difficult to recover the CNC device. Can not.

In such a case, as shown in FIG. 5, the SRAM 3 backed up by the battery with the auxiliary power supply 4 is mounted on the printed circuit board 11 together with the auxiliary power supply 4 and the
It is also conceivable to restore the data by removing the printed circuit board 11 from the CNC device 1 in which the abnormality has occurred and attaching it to the normal CNC device 1 '. However, in the configuration in which backup is performed by the auxiliary power supply, there is a problem in that the auxiliary power supply may be short-circuited due to an erroneous operation in the detachment operation of the printed circuit board 11 and data may be lost.

Accordingly, the present invention solves the above-mentioned conventional problems, and can frequently back up dynamic data without using an external storage medium and an auxiliary power supply. An object of the present invention is to provide a data backup method for a CNC device that can restore data without losing it.

[0009]

According to the data backup method of the CNC device of the present invention, in the data management of the CNC device, the frequently-rewritten dynamic data stored in the volatile memory during the normal operation of the CNC device is backed up. When the voltage drops, the data stored in the volatile memory is automatically written in the writable nonvolatile memory to back up the data.

In a CNC device, a program,
Static data with a low rewrite frequency such as system parameters are stored in a non-volatile memory such as FROM (flash ROM), and dynamic data with a high rewrite frequency such as position data are stored in a volatile memory such as an SRAM (static RAM). I do. Here, the static data and the dynamic data are classified according to the rewriting frequency, and data that is not rewritten in the normal operation of the CNC device is defined as static data.
Data that is frequently rewritten according to the operation of the CNC device is defined as dynamic data. The present invention backs up this dynamic data.

According to the data backup method of the CNC apparatus of the present invention, during normal operation, dynamic data such as position data which is frequently rewritten is stored in an SRAM (Static RA).
M) to perform a data rewriting operation with a volatile memory such as M). At this time, the non-volatile memory that backs up the dynamic data retains the dynamic data stored in the previous write even if the dynamic data changes.

According to the CNC device of the present invention, when the power supply voltage drops during the operation of the CNC device, or when the power supply is cut off or the like, the contents stored in the volatile memory at that time can be written. Automatically writes to a non-volatile memory and backs up data to the non-volatile memory.

Thus, the dynamic data is stored in the battery-backed-up volatile memory, and the data is backed up in the non-volatile memory. Generally, a volatile memory has a high frequency of failures when power is turned on. However, according to the present invention, even if data is lost due to a failure occurring in the volatile memory, the latest data is stored in the nonvolatile memory. Because it is backed up,
Data can be restored. Even if the data in the volatile memory is lost due to a drop in the voltage of the auxiliary power supply or a failure in the auxiliary power supply circuit section, the data at the time of the voltage drop is backed up to the nonvolatile memory. Can be performed (corresponding to claim 1).

In the automatic writing of data from the volatile memory to the nonvolatile memory, the voltage is monitored by voltage monitoring means provided in the CNC device, and when the voltage drops,
Based on this voltage drop, data is transferred from the volatile memory to the nonvolatile memory before the power supply voltage completely drops. Thus, automatic writing can be performed without requiring manual data writing operation (corresponding to claim 2). Non-volatile memory is CN
It can be configured to be detachable from the C device, and CN
When it is difficult to read out the dynamic data stored in the volatile memory due to the failure of the C device or when the data in the volatile memory is lost, the nonvolatile memory backing up the data is removed from the CNC device, and the normal CNC is used. The dynamic data can be read out to the volatile memory by being attached to the device, and the operation by the CNC device can be continued (corresponding to claim 3).

A static RAM can be used as a volatile memory, and a FROM is used as a non-volatile memory.
Can be used. Since the static RAM has no limitation on the number of times of writing, it can cope with the storage of dynamic data that changes frequently. Further, the FROM which does not require a battery backup has a limitation in the number of times of writing. However, according to the present invention, it can be dealt with by reducing the number of times of writing by performing rewriting when the voltage drops. Further, since the FROM does not require a battery, no voltage is applied to the storage element,
It is possible to prevent data loss due to an operation error at the time of attachment / detachment (corresponding to claim 4).

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 2 is a diagram for explaining a data backup method of the CNC device according to the present invention in FIG. 1 with respect to a configuration example of the embodiment of the present invention. In FIG. 1, a CNC device 1 includes a CNC device main body 2 and an SRA for storing dynamic data with a high frequency of rewriting such as position data.
M3 and the auxiliary power supply 4 of the SRAM 3 and the CNC device 1
And a power supply device 5 for driving the SRAM 3.
Is provided via a socket 8 for backing up the stored contents of the above. Writing of data from the SRAM 3 to the FROM 7 is performed by a command signal from the voltage monitoring circuit 6. The voltage monitoring circuit 6 monitors the voltage of the power supply device 5, determines that the voltage has dropped when the power supply voltage is equal to or lower than the set voltage, and sends a command signal for writing data from the SRAM 3 to the FROM 7.

The CNC device 1 is provided with a FRO (not shown).
A non-volatile memory such as M is provided, and static data such as programs, system parameters, and the like which are not frequently rewritten are stored.

In the CNC device 1, in a normal operation,
The program and system parameters are read from a not-shown FROM to perform an operation, and the SRAM 3 is rewritten with frequently changing dynamic data such as position data.

During this time, the voltage monitoring circuit 6 monitors the voltage of the power supply 5 and detects a voltage drop when the power supply voltage drops below the set voltage, and stores the voltage stored in the SRAM 3 at that time. A command signal for writing the contents to the FROM 7 is output to perform data copy processing.

FIG. 2 is a diagram for explaining the operation of the voltage monitoring circuit. FIG. 2A shows a case where the power supply 5 is turned off. Power supply voltage V indicated by a solid curve in the figure
Starts to drop due to the power cutoff, and when the voltage becomes equal to or lower than a predetermined set voltage V0, it is determined to be a voltage drop and the voltage drop is detected (FIG. 2B). The voltage monitoring circuit outputs a command signal for writing data based on the detection of the voltage drop, and stores the stored content in the SRAM 3 into F
The data is written in the ROM 7 and a copy process is performed. As a result, the same storage contents of the SRAM 3 are stored in the FROM 7 and the data is backed up.

Note that the writing process from the SRAM 3 to the FROM 7 can be performed during dt during which a holding voltage sufficient for writing is held before the power supply voltage is completely reduced. The FROM 7 is detachably attached by a socket 8. By removing the FROM 7 from the socket 8, the backed up data can be used for another CNC apparatus 1 ′. FIG. 3 is a diagram illustrating an example of using backup data. FIG.
Is the CN whose power cannot be turned on or whose normal operation cannot be performed.
An example is shown in which the data of the C device 1 is restored by the CNC device 1 ′ using the backup data stored in the FROM 7.

The dynamic data of the CNC device 1 is stored in the SRAM 3, and the dynamic data at the time of a voltage drop such as a previous power-off is stored in the FROM 7 as backup data. When a voltage drop or power interruption occurs during the operation of the CNC device 1, the data of the SRAM 3 is written into the FROM 7 by the voltage monitoring circuit 6, and the data is copied.
Update backup data and store the latest data.

FROM 7 storing backup data
Is removed from the socket 8, and the FROM 7 is attached to the socket 8 'of another CNC device 1'. CNC device 1 '
Reads the backup data stored in the FROM 7 and writes it in the SRAM 3 ′. With this, CNC
The device 1 ′ performs a recovery operation using the data written in the SRAM 3 ′, and can continue the operation of the CNC device 1.

[0024]

As described above, according to the data backup method of the CNC device of the present invention, frequent dynamic data backup can be performed without using an external storage medium and an auxiliary power supply. In addition, data can be restored without data loss due to an operation error.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a data backup method of a CNC device according to the present invention.

FIG. 2 is a diagram for explaining a voltage monitoring operation of the present invention.

FIG. 3 is a diagram illustrating an example of using backup data.

FIG. 4 is a diagram for explaining data backup of a CNC device provided with another storage medium.

FIG. 5 is a diagram for explaining another backup of data of the CNC device.

[Explanation of symbols]

 1, 1 'CNC device 2, 2' CNC device main body 3, 3 'SRAM 4, 4' Auxiliary power supply 5, 5 'Power supply device 6, 6' Voltage monitoring circuit 7 FROM 8, 8 'socket 10 External memory 11 Printed circuit board 12 Connector

Claims (4)

[Claims] In data management of a CNC device, a CN
By storing dynamic data having a high rewriting frequency in the volatile memory during the normal operation of the C device and automatically writing the storage contents of the volatile memory to the writable nonvolatile memory when the voltage drops, A data backup method for a CNC device, which backs up data. 2. The data backup of a CNC device according to claim 1, wherein the automatic writing is performed by transferring data from a volatile memory to a nonvolatile memory based on detection of a voltage drop by voltage monitoring means. method. 3. The method for backing up data of a CNC device according to claim 1, wherein the nonvolatile memory is detachable from the CNC device. 4. The method according to claim 1, wherein said volatile memory is a static RAM, and said nonvolatile memory is a FROM.