JP2002358142A - Control device - Google Patents

Abstract

(57) Abstract: A power supply to a storage device accessed by a control LSI is performed without adversely affecting the operation of the control LSI in each of a normal operation mode and a low power operation mode. To provide a control device capable of stopping even in a power operation mode. A control LSI disconnects an internal bus from the system bus when shifting to the low power operation mode,
Only when a predetermined waiting time has elapsed from the point in time when a start request was generated from the start request generation unit in the low power operation mode and power supply to the main power supply operation unit including the storage device was restarted from the main power supply The internal bus is connected to the system bus, access to the storage device via the system bus is started, and the device control operation in the normal operation mode is restarted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device such as a facsimile machine, and more particularly, to a main power supply operating unit which is operated by a main power supply supplied in a normal operation mode and stopped in a low power operation mode. A control LSI and a start-up request generation unit which are always operated by a sub-power supply, and are connected to the control LSI via a system bus;
A storage device accessed via the system bus for controlling the device operation in the normal operation mode by I. When a predetermined low-power operation mode transition factor occurs in the normal operation mode, the control LSI The power supply from the main power supply to the main power supply operation unit is stopped to shift to the low power operation mode. In the low power operation mode, when a start request is generated from the start request generation unit, the control LSI The present invention relates to a control device having a power saving function for restarting power supply to the main power supply operation section from the power supply and returning to the normal operation mode.

[0002]

2. Description of the Related Art Conventionally, taking a facsimile apparatus as one example of a control apparatus as an example, a configuration for generating a start request from a low power operation mode to a normal operation mode, such as a control LSI, a switch, and a sensor unit. Scanner, plotter, N
A main power operation unit such as a CU and an operation unit; and a storage device including a RAM, a ROM, and the like. In a normal operation mode, the control LSI connects a system bus connecting the control LSI and the storage device. Performs a normal operation as a facsimile apparatus that controls the main power supply operation unit while accessing the storage device via the storage device, and in the normal operation mode, there is no operation input for a certain period of time, no reception for a certain period of time, or the like. If a transition factor to the low-power operation mode occurs, in the facsimile apparatus having a function of stopping supply of the main power to the main power operation unit and transitioning to the low-power operation mode, When the activation request is generated in the low power operation mode, the supply of the main power to the main power operation unit is resumed, and at the same time, the control LSI Read to the storage device via the Sutemubasu, it starts normal device overall control of the operation mode to write access.

[0003]

Therefore, assuming that the storage device belongs to the main power supply operation section operated by a main power supply, the above-mentioned storage device is required to be switched from the normal operation mode to the low power operation mode. Power supply to the storage device is stopped, which adversely affects the internal operation of the control LSI bus-connected to the storage device via the system bus.

When shifting from the low power operation mode to the normal operation mode, it takes a certain time until the voltage supplied from the main power supply to each part constituting the main power supply operation section reaches a steady voltage. Therefore, if it is assumed that the storage device belongs to the main power supply operation unit that operates on a main power supply, the storage device shifts from the low-power operation mode to the normal operation mode and immediately returns from the LSI. Cannot access the storage device, the device control in the normal operation mode of the control LSI cannot be started normally.

Therefore, conventionally, it is necessary to continue supplying power to the storage device accessed by the control LSI not only in the normal operation mode but also in the low power operation mode. There is a problem that the effect of reducing power consumption at the time is not sufficient.

The present invention has been made in view of the above circumstances, and supplies power to a storage device accessed by a control LSI in the operation of the control LSI in each of a normal operation mode and a low power operation mode. It is an object of the present invention to provide a control device capable of stopping even in the low power operation mode without giving any adverse effect.

[0007]

According to a first aspect of the present invention, there is provided a control device which is operated by a main power supply which is supplied in a normal operation mode and is stopped in a low power operation mode. Control LSI operated by power supply
And a start request generation unit, and a storage device connected to the control LSI via a system bus and accessed via the system bus for device operation control in the normal operation mode by the control LSI. When a predetermined low-power operation mode transition factor occurs in the normal operation mode, the control LSI stops power supply from the main power supply to the main power supply operation unit and transitions to the low-power operation mode. A power-saving function that, when an activation request is generated from the activation request generation unit in the operation mode, the control LSI restarts power supply from the main power supply to the main power supply operation unit and returns to the normal operation mode. The control device, wherein the storage device belongs to the main power supply operation unit, and the control LSI is configured to switch to the low power operation mode. A bus separating unit for separating the external bus from the system bus, and a point in time when a start request is generated from the start request generating unit in the low power operation mode and power supply from the main power supply to the main power supply operating unit is restarted. A timer means for measuring a predetermined waiting time from; anda bus connection means for connecting the internal bus to the system bus only after the time measurement of the predetermined waiting time by the timer means has timed out. An access to the storage device via the system bus is started only after the predetermined waiting time has timed out, and the device control operation in the normal operation mode is restarted.

The control device according to a second aspect is the control device according to the first aspect, further comprising setting means for arbitrarily setting the predetermined waiting time measured by the timer means. And

A control device according to a third aspect of the present invention includes a main power supply operation unit which is supplied in a normal operation mode and is operated by a main power supply which is stopped in a low power operation mode;
A control LSI and a start-up request generation unit which are always operated by a sub-power supply, are connected to the control LSI via a system bus, and are accessed via the system bus for device operation control in the normal operation mode by the control LSI. When a predetermined low-power operation mode transition factor occurs in the normal operation mode, the control LSI stops power supply from the main power supply to the main power supply operation unit, and the low-power operation The control LSI restarts power supply from the main power supply to the main power supply operation unit and returns to the normal operation mode when a start request is generated from the start request generation unit in the low power operation mode A control device having a power saving function, wherein the storage device belongs to the main power supply operation unit, and the control LSI Bus separation means for disconnecting an internal bus from the system bus at the time of transition to the low power operation mode; and a main power operation unit from the main power supply when a start request is generated from the start request generation unit in the low power operation mode Power supply monitoring means for monitoring whether a supply voltage from the main power supply to the main power supply operation unit has reached a predetermined steady voltage after restarting power supply to the power supply, and the power supply monitoring means Bus connection means for connecting the internal bus to the system bus only when it is detected that the supply voltage to the main power supply operation section has reached the predetermined steady-state voltage, wherein the power supply monitoring means Only when it is detected that the supply voltage to the main power supply operation unit has reached the predetermined steady-state voltage, access to the storage device via the system bus is started, and Characterized by resuming the device control operation of the normal operation mode.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described in detail.

First, FIG. 1 shows a block configuration of a facsimile apparatus 1 according to an embodiment of the present invention. In FIG. 1, the facsimile apparatus 1 includes a main power supply operation unit 10 that operates with power supplied from a main power supply 2 and a sub power supply operation unit 20 that operates with power always supplied from a sub power supply 3.
It is composed of

The power supply from the main power supply 2 to the main power supply operation unit 10 is controlled by a main power supply control signal from a main power supply control unit 32 in a facsimile control LSI 30 described later in detail.

The main power supply operation unit 10 includes a first storage device 11,
Second storage device 12, scanner 13, plotter 14, NC
U15, operation display unit 16, and facsimile control L
A system bus 17 which is a signal line for accessing the first storage device 11 and the second storage device 12 from the SI 30
It is composed of

The first storage device 11 has a facsimile control L
The control unit 31 in the SI 30 stores a system program for controlling the entire apparatus. The second storage device 12 is a random access memory used for a stack area, a work area of the system, and the like when the control unit 31 executes a system program.

The scanner 13 optically scans a document and transfers the image information to a scanner control unit 35 in the facsimile control LSI 30. Plotter 14
Is the plotter control unit 3 in the facsimile control LSI 30
6 is for physically converting the image data from image data 6 into an image.

The NCU 15 is a facsimile control LSI 3
It is controlled by the communication control unit 37 in 0 to perform network control. The operation unit 16 includes various keys, switches, and a display unit necessary for transmission and reception operations.
It is controlled by the operation unit control unit 38 in the facsimile control LSI 30.

The sub-power supply operation unit 20 includes a switch sensor 2
1 and a facsimile control LSI 30.

The switch sensor 21 is a document presence / absence sensor, a cover sensor, a specific switch of the operation unit 16, and the like.
The switch and sensor information are passed to a start request detecting unit 33 in the facsimile control LSI 30 as a start request for prompting a return from the low power operation mode to the normal operation mode.

The facsimile control LSI 30 includes a control unit 3
1, main power control unit 32, activation request detection unit 33, compression / decompression unit 34, scanner control unit 35, plotter control unit 35, communication control unit 37, operation display unit control unit 38, internal bus 39,
And an input / output unit 40.

The control section 31 is a mode in which power is supplied from the main power supply 2 to the main power supply operation section 10 in accordance with the system program stored in the first storage device 11, and a normal operation as a facsimile apparatus is performed. , A microcomputer that controls the entire apparatus in a normal operation mode. Further, the control unit 31 is configured to switch from the main power supply 2 to the main power supply operation unit 1.
Control for shifting to a low-power operation mode, which is an operation mode for stopping power supply to 0, and control for returning from the low-power operation mode to the normal operation mode are performed.

The main power supply control unit 32 is asserted by the control unit 31 in the normal operation mode when a power saving transition factor such as continuation of a certain period of time without an operation input or continuation of a certain period of time without an incoming call occurs. When the power-saving operation status signal is detected, the power supply to the main power supply operation unit 10 is stopped by asserting the main power supply control signal to the main power supply 2, while the start-up signal from the start-up request detection unit 33 is output. Is detected, the power supply to the main power supply operation unit 10 is restarted by negating the main power supply control signal.
When the power-saving operation status signal from the control unit 31 is asserted, the main power supply control unit 32 asserts a system bus control signal to the input / output unit 40, and the internal bus 39
From the external system bus 17. Further, the main power control unit 32 starts counting a predetermined waiting time T by the timer unit 32a from the time when the activation signal from the activation request detection unit 33 is asserted and the main power control signal is asserted. When the unit 32a times out, it asserts an interrupt signal for instructing the control unit 31 to return from the low power operation mode to the normal operation mode, and negates the system bus control signal to the input / output unit 40. , The internal bus 39 is connected to the external system bus 17.

The start request detecting section 33 asserts a start signal to the main power control section 33 when detecting the assertion of an external or internal start request from the switch sensor 32.

The compression / decompression section 34 is for performing compression / decompression processing of image information. The scanner controller 35 performs necessary image processing on image data obtained by A / D conversion of an analog image signal from the scanner 13. The plotter control unit 14 is for outputting image data to the plotter 14. The communication control unit 37
In addition to a modem function for modulating and demodulating a communication signal exchanged with a line (not shown) via the NCU 15, the NCU 15
This is for controlling the network control operation. The operation unit control unit 38 passes key and switch information of the operation unit 16 to the control unit 31 via the internal bus 39, and passes display information from the control unit 31 to the operation unit 16.

The internal bus 39 includes a control unit 31, a main power supply control unit 32, a start request detection unit 33, a compression / decompression unit 34, a scanner control unit 35, a plotter control unit 36, a communication control unit 37,
And a facsimile control LSI 3 of the operation unit control unit 38
0 is an internal signal line for exchanging data with each unit.

The input / output unit 40 connects and disconnects the internal bus 39 and the system bus 17.
3 shows a configuration of the input / output unit 40 of FIG.

In FIG. 1, an input / output unit 40 serving as a bus separating unit and a bus connecting unit controls a three-state buffer in response to a system bus control signal from a main power supply control unit 32, and outputs data buses (D0 to Dn). , An address bus (A0 to An), a chip select signal (CS0 to CSn), a read signal (RD), a write signal (W
By setting R) in a high impedance state, the internal bus 39 is disconnected from the system bus 17. Since the data bus is a bidirectional bus, a logical sum signal of the terminal direction control signal and the system bus control signal is transmitted to the data bus in order to exchange data via the system bus 17 in the normal operation mode. It is supplied to a three-state buffer.

In the normal operation mode, the control unit 31
While accessing the first storage device 11 and the second storage device via the system bus 17 connected via the internal bus 39 and the input / output unit 40, each unit of the device is controlled to perform the original operation as a facsimile device, That is, facsimile transmission processing, facsimile reception processing, various registration / setting operation processing, and the like are performed. However, there is no key or switch input signal from the operation unit control unit 38 for a certain period of time, or the communication control unit 3
When a transition factor to the low-power operation mode occurs, for example, a state in which there is no incoming detection signal from the receiver 7 for a certain period of time, FIG.
As shown in the timing chart of FIG.
Assert a low power operation status signal for

Then, the main power control unit 32 immediately asserts the main power control signal and the system bus control signal.
The power supply from the main power supply 2 to the main power supply operation unit 10 is stopped by the assertion of the main power supply control signal, the voltage thereof also decreases, and the main power supply operation unit including the first storage device 11 and the second storage device 12 When the operation stops, the signal level of the system bus 17 also drops at the same time, but the internal bus 39 of the facsimile control LSI 30 is disconnected from the system bus 17 by the control of the input / output unit 30 by assertion of the system bus control signal. Therefore, there is no problem in the operation of the facsimile control LSI 30.

Thereafter, when an activation request from the switch sensor 31 or the like is asserted, an activation signal from the activation request detection unit 33 to the main power supply control unit 32 is also asserted.

At the same time, the timer 32a starts counting a time constant T as a predetermined waiting time.

Thus, the main power supply control signal from the main power supply control unit 32 to the main power supply 2 is negated, and the power supply from the main power supply 2 to the main power supply operation unit 10 is restarted. But,
It takes a certain period of time for the supply voltage from the main power supply 2 to the main power supply operation unit 10 to reach a steady level required for the operation of each unit of the main power supply operation unit 10.

Therefore, the time constant T set in the timer section 32a is set to a value sufficient for the voltage supplied from the main power supply 2 to reach a steady level.

As the time constant T set in the timer section 32a, a fixed value may be set in advance.
The value of the time constant T may be arbitrarily set by an operation input or the like via the. In that case, the shortest value that can be different for each device and that is suitable for the time required for the supply voltage from the main power supply 2 to reach the steady level can be set as the time constant T, and until the time when the device returns to the normal operation mode. Can be made as short as possible.

When the timer 32a times out the measurement of the time constant T, the main power controller 32
Is negated, and the internal bus 39 is reconnected to the system bus 17. At that point, the first storage device 11 and the second storage device 12 are supplied with a steady-level voltage required for operation from the main power supply 2 and are in a state where normal operation is possible. It is in a state that can respond to.

The main power supply control unit 32 includes a timer unit 32
When the time measurement of the time constant T by a times out, the control unit 31 asserts an interrupt signal instructing a return to the normal operation mode.

The control unit 31 resumes control of the normal operation mode for the first storage device 11 and the second storage device 12 in response to the assertion of the interrupt signal from the main power supply control unit 32.

As described above, when shifting from the normal operation mode to the low power operation mode, the facsimile control LSI 30
The internal bus 39 is separated from the system bus 17 so that the operation inside the facsimile control LSI 30 is not hindered, and the internal bus 39 is immediately connected to the system bus 17 at the time of transition from the low power operation mode to the normal operation mode. Instead of causing the control unit 31 to start the control of the normal operation mode, wait until the first storage device 11 and the second storage device 12 can operate normally, and then connect the internal bus 39 to the system bus 17. Since the control unit 31 starts the control of the normal operation mode, in the normal operation mode, the facsimile control LSI is connected via the system bus 17.
The first storage device 11 and the second storage device 12 accessed from the internal bus 39 in the 30 belong to the main power supply operation unit 10, and even if the power supply is stopped at the time of shifting to the low power operation mode, the facsimile is performed. The internal bus 39 of the control LSI 30 can operate normally without any adverse effect, and can operate normally in the normal operation mode after returning from the low power operation mode.

As a result, the conventional facsimile control L
The power supply to the first storage device 11 and the second storage device 12 whose power supply could not be stopped even in the low power operation mode in order to avoid an adverse effect on the internal bus 39 in the SI 30 is
In the low-power operation mode, the operation can be stopped, and an effect that the power can be further reduced can be obtained.

In the configuration shown in FIG. 1, as shown in the timing chart of FIG. 3, after the main power control unit 32 detects the assertion of the start signal from the start request detecting unit, the input / output unit 30 The waiting time until the system bus control signal is negated or the interrupt signal to the control unit 31 is asserted is fixed and set in advance to the time constant T by the timer unit 32a. If
It is not possible to flexibly cope with a case where the optimal time constant T changes due to a change in the specification of the main power supply 2 or the like.

Therefore, the timer section 32a of the main power supply control section 32 in the configuration shown in FIG.
The power supply monitoring unit 32b is replaced, the supply voltage from the main power supply 2 to the main power supply operation unit 10 is monitored, and the time required for the supply voltage to reach the steady voltage is set as shown in the timing chart of FIG. From when the power supply control unit 32 detects the assertion of the activation signal from the activation request detection unit to when the system bus control signal to the input / output unit 30 is negated or the interrupt signal to the control unit 31 is asserted. By setting the waiting time, the time required to reach the steady voltage due to a change in the specification of the main power supply 2 or the like (the time constant T in the timer unit 32a).
) Can be flexibly dealt with, and the trouble of changing the setting can be saved.

In the above-described embodiment, the present invention is applied to a facsimile apparatus. However, the present invention is not limited to this, and a control device in which a control LSI accesses an external storage device and performs a normal operation. In addition, as long as it has a low power operation mode, it can be similarly applied.

[0042]

According to the first aspect of the present invention, when shifting from the normal operation mode to the low power operation mode,
Disconnecting the internal bus of the control LSI from the system bus so as not to hinder the operation inside the control LSI;
When shifting from the low power operation mode to the normal operation mode,
Rather than immediately connecting the internal bus to the system bus and starting control in the normal operation mode, wait until the supply voltage from the main power supply to the storage device becomes stable and normal operation is possible, Since the control of the normal operation mode is started by connecting the internal bus to the system bus, the storage device accessed from the internal bus in the control LSI via the system bus in the normal operation mode Belongs to the main power supply operation section, and can operate normally without any adverse effect on the internal bus of the control LSI even when the power supply is stopped during the transition to the low power operation mode, and can return from the low power operation mode. Normal operation can be performed in the normal operation mode later. Thereby, the power supply to the storage device, which conventionally could not be stopped even in the low power operation mode in order to avoid an adverse effect on the internal bus in the control LSI, is stopped in the low power operation mode. Therefore, the effect that the power consumption can be further reduced is obtained.

According to the second aspect of the present invention, since the predetermined waiting time set in the timer section can be set arbitrarily, the supply voltage from the main power supply, which can be different for each device, becomes a steady level. The shortest value that matches the time required to reach can be set as the predetermined waiting time,
The advantage is obtained that the waiting time until the return to the normal operation mode can be shortened as much as possible without changing the circuit configuration.

According to the third aspect of the invention, in addition to the same effect as the first aspect, the internal bus is connected to the system bus to start accessing the storage device via the system bus. The timing of restarting the device control operation in the normal operation mode is monitored by monitoring the supply voltage of the main power supply, so that it can flexibly respond to changes in the time required until the supply voltage of the main power supply reaches a steady voltage. Thus, there is an effect that the trouble of changing the setting can be omitted.

[Brief description of the drawings]

FIG. 1 is a diagram showing a block configuration of a facsimile apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration for separating and connecting buses of an input / output unit of the facsimile apparatus according to the embodiment of the present invention.

FIG. 3 is a view showing a chart of operation timing in the facsimile apparatus having the block configuration shown in FIG. 1;

FIG. 4 is a diagram showing another example of the block configuration of the facsimile apparatus according to the embodiment of the present invention, which is different from FIG.

5 is a diagram showing a chart of operation timing in the facsimile apparatus having the block configuration shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Facsimile apparatus 2 Main power supply 3 Sub power supply 10 Main power supply operation part 11 First storage device 12 Second storage device 13 Scanner 14 Plotter 15 NCU 16 Operation part 17 System bus 20 Sub power supply operation part 21 Switch / sensor 30 Facsimile control LSI 31 Control unit 32 Main power control unit 32a Timer unit 32b Power monitoring unit 33 Activation request detection unit 34 Compression / expansion unit 35 Scanner control unit 36 Plotter control unit 37 Communication control unit 38 Operation unit control unit 39 Internal bus

Claims (3)

[Claims] 1. A main power supply operation section which is operated by a main power supply which is supplied in a normal operation mode and is stopped in a low power operation mode, a control LSI and a start request generation section which always operate by a sub power supply, A storage device connected to the control LSI via a system bus and accessed via the system bus for controlling the device operation in the normal operation mode by the control LSI, wherein a predetermined low power is supplied in the normal operation mode When an operation mode shift factor occurs, the control LSI stops power supply from the main power supply to the main power supply operation unit and shifts to the low power operation mode, and in the low power operation mode, the start request generation unit When an activation request is issued from the
A control device provided with a power saving function, wherein the SI resumes power supply from the main power supply to the main power supply operation unit and returns to the normal operation mode, wherein the storage device includes the main power supply operation unit The control LSI includes a bus separating unit that separates an internal bus from the system bus when the control LSI shifts to the low power operation mode;
Timer means for measuring a predetermined waiting time from the point in time when a start request is generated from the start request generation unit in the low power operation mode and power supply from the main power supply to the main power supply operation unit is restarted, Bus connection means for connecting the internal bus to the system bus only after the timing of the predetermined waiting time by the timer means has timed out,
The control device, wherein the access to the storage device via the system bus is started and the device control operation in the normal operation mode is resumed only after the timing of the predetermined waiting time by the timer means times out. . 2. The control device according to claim 1, further comprising setting means for arbitrarily setting the predetermined waiting time measured by the timer means. 3. A main power supply operation unit which is operated by a main power supply which is supplied in a normal operation mode and is stopped in a low power operation mode, a control LSI and a start request generation unit which are always operated by a sub power supply, A storage device connected to the control LSI via a system bus and accessed via the system bus for controlling the device operation in the normal operation mode by the control LSI, wherein a predetermined low power is supplied in the normal operation mode When an operation mode shift factor occurs, the control LSI stops power supply from the main power supply to the main power supply operation unit and shifts to the low power operation mode, and in the low power operation mode, the start request generation unit When an activation request is issued from the
A control device provided with a power saving function, wherein the SI resumes power supply from the main power supply to the main power supply operation unit and returns to the normal operation mode, wherein the storage device includes the main power supply operation unit The control LSI includes a bus separating unit that separates an internal bus from the system bus when the control LSI shifts to the low power operation mode;
In the low power operation mode, after a start request is generated from the start request generation unit and power supply from the main power supply to the main power supply operation unit is restarted, supply from the main power supply to the main power supply operation unit A power supply monitoring unit that monitors whether a voltage has reached a predetermined steady-state voltage, and the power supply monitoring unit detects that a supply voltage from the main power supply to the main power supply operation unit has reached the predetermined steady-state voltage. Bus connection means for connecting the internal bus to the system bus for the first time,
The power supply monitoring unit starts accessing the storage device via the system bus only after detecting that the supply voltage from the main power supply to the main power supply operation unit has reached the predetermined steady-state voltage. A control device for restarting the device control operation in the normal operation mode.