JPH07107674A - Power supply controlling device - Google Patents

Abstract

PURPOSE:To rationalize the control of the power supply of an electronic apparatus, which is driven with a battery, by turning OFF the power supply of the first electronic apparatus when the power supply of the first electronic apparatus, wherein the battery is the power supply, is in the ON state and the battery voltage has a value smaller than the specified value. CONSTITUTION:In a interface part 10a on the side of a printer, the power supply voltage of a battery 21a is inputted into a power-supply driving circuit 20c when a power transistor 20b is turned ON with a switching transistor 20a, and the power is supplied into each part. The ON/OFF control signal of the switching transistor 20a is transferred from a interface 30a on the side of an electronic computer through a signal line 23a. When the battery voltage supplied from the power-supply driving circuit 20c becomes lower than the internal working voltage, a CPU 14 outputs the reset signal, and the supply of the battery voltage to each part from the power-supply driving circuit 20c is stopped. Thus the power supply control of the electronic apparatus such as the printer and the electronic computer driven by the battery 21a can be adequately performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power management device for battery-powered electronic equipment.

[0002]

2. Description of the Related Art Conventionally, there are various methods for power management of a plurality of electronic devices such as a case where a printer is connected to an electronic computer. For example, there is one in which a battery is provided only in one of the electronic devices and power is supplied from the battery of one of the electronic devices by turning on / off the power of the other electronic device. Alternatively, there is a device in which batteries are provided in both electronic devices and a voltage drop of each battery is detected. Further, when one of the electronic devices detects a voltage drop of the battery and interrupts the communication of the data while data is being communicated between the electronic devices, the other electronic device waits for the time when the data is not transmitted. In some cases, the measurement ends and the communication ends when a timeout occurs.

Further, in battery-powered electronic equipment, the remaining capacity of the battery is detected and a warning that the remaining capacity is low is displayed in order to inform the battery replacement time or recharge time.

[0004]

However, there are various problems as described below. When only one electronic device has a battery, it is necessary to connect a plurality of electronic devices and operate at the same time so that the battery is okay.
For example, when a printer without a battery is connected to a computer, the power consumption of the printer is overwhelmingly higher than that of the computer, and the computer always has an excessive battery even when the printer is not used. I had to.

Even if the computer or the communication cable for the modem is not connected to the computer and cannot be used, as long as the power cable is connected, the printer or modem cannot be turned off unintentionally and the power is turned on unintentionally. The battery may be exhausted due to. Furthermore, when both electronic devices have batteries, each must have a switch for turning the power on and off and display means for displaying the voltage drop of the battery, and the user needs to confirm both displays. there were.

Further, when the voltage drop of the battery is detected and the data communication is interrupted, it is necessary to have an unnecessary waiting time such as a malfunction due to the handshake of the communication or the occurrence of a timeout.

Further, when the display means for notifying the replacement time or the recharge time of the battery is provided, dedicated hardware must be incorporated to detect the remaining capacity of the battery. Moreover, it was difficult to determine the remaining capacity unconditionally. For example, the time from when a hard disk is frequently used to when it is not used is different from the time when it is warned that the remaining capacity is low until it becomes inoperable. It happens too early for me. In addition, the remaining capacity is not always displayed, and since it will be warned when it drops, it is unclear when the remaining capacity will be low and the warning will be issued, so be worried when taking it to a place without power supply. For the time being, it will be charged, and the deterioration of the battery will be accelerated.

[0008] Therefore, an object of the present invention is to provide a power management device that appropriately manages the power of a battery-driven electronic device.

[0009]

In order to achieve the above object, a power management apparatus of the present invention connects a first electronic device having a battery as a power source to a second electronic device, The device is a power management device that manages the power supply of the first electronic device, and the second electronic device includes a battery voltage detection unit that detects a battery voltage of the first electronic device, and the first electronic device. When the power supply of the electronic device is in the ON state, the comparing means for comparing the battery voltage detected by the battery voltage detecting means with a predetermined value, and when the battery voltage is equal to or less than the predetermined value by the comparing means. Switching means for turning off the power supply of the first electronic device.

Further, the power management apparatus of the present invention comprises a control circuit which uses a battery as a power source and a switch circuit which turns on and off the power source. The control circuit is energized after the power source is turned on by the switch circuit. , A signal generating circuit for generating an interrupt signal of a constant cycle, a counter for storing the number of interrupt signals generated by the interrupt signal generating circuit, and a display of energization time based on the number of interrupt signals stored in the counter And a display circuit for performing.

[0011]

In the power management device of the present invention, the first electronic device, which uses a battery as a power source, is connected to the second electronic device, and the second electronic device manages the power supply of the first electronic device. The battery voltage detection means provided in the second electronic device detects the battery voltage of the first electronic device, and when the power supply of the first electronic device is in the ON state, the battery voltage is The battery voltage detected by the detection means is compared with a predetermined value by the comparison means, and the switching means turns off the power source of the first electronic device when the battery voltage is equal to or lower than the predetermined value by the comparison means.

In the power management apparatus of the present invention, a battery is used as the power source of the control circuit, the switch circuit turns on / off the power source, and the switch circuit provided in the control circuit turns on the power source to generate a signal during energization. A circuit generates an interrupt signal of a fixed cycle, a counter stores the number of interrupt signals generated by the interrupt signal generation circuit, and a display circuit displays a power-on time based on the number of interrupt signals stored in the counter. By.

[0013]

EXAMPLE Next, an example of the power management apparatus of the present invention will be described.

[First Embodiment] FIG. 1 is a block diagram showing the arrangement of an information processing apparatus 5 to which the power management apparatus of the first embodiment is applied. The information processing device 5 according to the present exemplary embodiment is the printer 10.
And a computer 1 and a printer 1
0 and the computer 30 are connected by a detachable cable 23. The printer 10 is a well-known CP via the bus 13.
A U14, a ROM 15 for storing a processing program, a RAM 16 for storing data as a working area, an LED display 17 for displaying the state of the printer 10, a printing unit 18 for printing, and a communication circuit 19 for communicating with the outside are provided. The power supply circuit 20 is provided with a battery pack 21, and the power supply circuit 20 and the battery pack 21 are connected to a connector 22 by cables 25 and 26. R
A low battery flag 16a is assigned to the AM 16.

The electronic computer 30 has a well-known CPU 37, a ROM 38 for storing a processing program, and a well-known CPU 37 via a bus 36.
The working area includes a RAM 39 for storing data and application programs, an LCD display 40, a keyboard 41, communication circuits 42, 43, and a power supply monitor circuit 49 for monitoring the power supply of the printer 10 connected via the connector 45. The power supply circuit 51 includes a battery pack 54 and supplies power to each unit of the electronic computer 30. From the connector 45 to the communication circuit 42 and the power supply monitor circuit 49
Cables 48 and 47 are provided in the. Communication circuit 4
A connector 60 for connecting to an external device is connected to 3. Further, the low battery flag 3 is stored in the RAM 39.
9a and ON flag 39b are assigned.

Next, the interface portion between the printer 10 and the electronic computer 30 will be described with reference to FIG.
A multi-core cable 23 is connected between the connector 22 of the printer 10 and the connector 45 of the electronic computer 30, and the multi-core cable 23 includes a power cable 23e and a signal line 2 which will be described later.
3a, 23b, 23c and 23d are stored in a bundle. Also,
The printer-side interface unit 10a includes the communication circuit 1
9, power supply circuit 20, battery pack 21 and connector 22
The computer-side interface unit 30a is composed of a communication circuit 42, a power supply monitor circuit 49, and a connector 45. In the printer-side interface unit 10a, when the power transistor 20b is turned on by the switching transistor 20a, the battery voltage of the battery 21a contained in the battery pack 21 is input to the power supply drive circuit 20c to supply power to each unit. The ON / OFF control signal of the switching transistor 20a is transmitted from the electronic calculator side interface 30a through the signal line 23a. When the ON / OFF control signal is at H level, the switching transistor 20a and the power transistor 20
Both b are turned on. When the battery voltage supplied by the power supply drive circuit 20c becomes lower than the internal operating voltage, the CPU
Reference numeral 14 outputs a reset signal to stop the supply of the battery voltage to each part by the power supply drive circuit 20c. The interrupt terminal INTB of the CPU 14 has an interface 30 on the electronic calculator side.
The collector terminal 19b of the transistor 19a driven by the low battery flag signal transmitted from a through the signal line 23b is connected. Further, signal lines 23c and 23d for transmitting control signals and data signals are provided between the buffers 19c and 42a. Further, the battery voltage of the battery 21a described above is supplied to the electronic calculator side interface 30a via the power cable 23e.
Of the power supply monitor circuit 49.

On the electronic computer side interface 30a side, a dummy load resistor 49a having a load similar to that of the printer 10 is connected to the power cable 23e of the power monitor circuit 49, and the other end of the load resistor 49a is connected. Is connected to the collector of a transistor 49b whose emitter is grounded. The load resistor 49a is a resistor for connecting a load to the battery 21a and checking the remaining capacity of the battery 21a as described later. The base of the transistor 49b is connected to the P3 port of the CPU 37, and when an H level signal is input to the transistor 49b from the P3 port, the transistor 49b is turned on and a voltage drop occurs in the load resistor 49a. The resistance value of the load resistor 49a is set so that a current slightly higher than the current supplied from the battery 21a flows when the printer 10 prints. Further, the power supply monitor circuit 49 has a comparator 49c.
Is provided and the battery voltage of the power cable 23c, which is dropped by the load resistor 49a, is the voltage dividing resistor 49a.
The voltage dividing resistors are connected to the non-inverting input terminal of the comparator 49c after being divided by d and 49e. The inverting input terminal divides the battery voltage on the electronic computer 30 side into a low battery voltage which is a reference voltage. 49f and 49g are provided. The output terminal of the comparator 49c is the CPU 37
Connected to the interrupt terminal INTA. Therefore,
The comparator 49c determines whether or not the battery voltage of the battery 21a does not become lower than the low battery voltage. The low battery voltage is set higher than the reset generation voltage of the printer 10 by about 0.2 [V]. When the battery voltage drops below the low battery voltage, the comparator 4
When the output voltage of 9c is L level, an interrupt signal is generated to the CPU 17. In response to this interrupt signal, the CPU 17 outputs an ON / OFF control signal from the output port P2 to the switching transistor 20a via the above-mentioned signal line 23a. In the printer-side interface 10a, assuming that the battery voltage of the battery 21a is low, the power transistor 20b controlled by the switching transistor 20a is turned off to disconnect the battery 21a from the power supply drive circuit 20c. Here, even if the power supply circuit 51 of the computer side interface 30a is cut off, the ON / OFF control signal output from the CPU 37 is at the L level, so the power supply of the printer 30 is cut off and the failure occurs. Safe is protected. Also, as mentioned above, CP
The U 37 exchanges control signals such as print data and ready and busy signals, which will be described later, with the CPU 14 via the buffer 42a.

Power management of the information processing apparatus 5 having the printer 10 and the electronic computer 30 having the above-described configurations will be described. FIG. 3 is a flowchart showing a printer power ON routine executed by the CPU 37 of the electronic computer 30. This routine is started according to the request from the application program. The CPU 37 is the printer 10
When the power is turned on, the 1-bit ON flag 39b and the low battery flag 39a assigned to the RAM 39 are set to the L level and initialized (steps S120 and S130). It is checked whether the interrupt terminal INTA of the CPU 37 is at the H level and is in the interrupt disabled state (step S14).
0). As described above, if the battery voltage on the printer 10 side is equal to or higher than the low battery voltage, the interrupt terminal INTA becomes H level.
It becomes the level voltage. When the interrupt terminal INTA is at the L level voltage, it means that the power cable 23e between the connectors 22 and 45 is not properly connected or the battery voltage of the printer 10 is lower than the low battery voltage. When the interrupt terminal INTA is at the L level voltage, "printer low battery" is set as the return code to the application program (step S
260), and this routine ends.

In step S140, the interrupt terminal INTA
When is at H level, the battery voltage is checked again. That is, the output port P3 of the CPU 37 is set to H.
The voltage of the level is set (step S150), the transistor 49b is turned on, and the resistor 49a having a dummy load equivalent to that when the printer 10 is printing is energized (step S160). As a result, the comparator 49
When the output from c becomes L level, the printer 10 is turned on.
Since there is a high possibility that a low battery will be generated immediately even if it is set to N, the output port P3 is returned to the L level (step S250) and then the process proceeds to step S260 and the present routine is ended.

If the battery voltage is checked at step S160 and it is still at the H level, then it is determined that there is no problem and the output port P3 is returned to the L level (step S170). Next, the interrupt process is registered (specifically, the interrupt vector is set) (step S180), and the interrupt terminal INTA is set to the L level to enable the interrupt (step S19).
0). After that, until the interrupt is disabled, the printer 1
When the battery voltage of 0 becomes equal to or lower than the low battery voltage, an interrupt occurs and the interrupt INTA process shown in FIG. 6 is executed. Next, an H level signal is output to the output port P2 (step S200). The switching transistor 20a of the power supply circuit 20 is turned on by the H level signal from the output port P2, and the printer 10 is turned on. The H level is written in the ON flag 39a of the RAM 39 to indicate that the printer 10 is in the power ON state (step S210). The return code is set to "normal end" (step S220), and the process returns to the application program. The application program can issue a print request to the printer 10 when the return code is “normal end”.

FIG. 4 is a flow chart showing the print request routine. This routine is started by a print request from the application program as described above. First, it is checked whether the ON flag 39b of the RAM 39 is at the H level (step S310). ON flag 39
When b remains at the L level, either the power of the printer 10 is not turned on or the printer power ON routine is not normally completed. Therefore, the L level signal is output again to the output port P2. Power off the printer 10 (step S470). Interrupt INTA
Prohibited (step S480), and then set the return code to "printer OFF" (step S490)
This routine ends. When the ON flag 39b is at the H level, it is then checked whether the low battery flag 39a is at the L level (step S320). This low battery flag 39a is a flag that is set to the H level in the above-mentioned interrupt INTA processing routine, and when it is at the H level, it means that a low battery has occurred. Therefore, "low battery" is set in the return code and this routine is executed. To finish. When the low battery flag 39a is at the L level, the presence or absence of print data is checked (step S330). If there is no print data, the return code is set to "normal end" and this routine ends. When there is print data, it is confirmed again whether the low battery flag 39a is at the L level. This is to constantly monitor the low battery in the loop. Here, when the low battery flag 39a is at the H level, the "printer low battery" is set as the return code and the present routine is terminated as described above. When the low battery flag 39a is at the L level, it is checked whether the control line 23c is abnormal (step S35).
0). When there is an abnormality in the control line 23c, the cause of abnormality is analyzed (step S440), the cause of abnormality is set in the return code (step S450), and this routine ends. When there is no abnormality in the control line 23c, it is checked whether the printer 10 is ready (step S360). When the printer 10 is in the busy state instead of the ready state, the printer 10 is executing internal processing,
Since data cannot be received, the process returns to step S340 and the low battery flag 39a is repeatedly checked. Steps S340, S until printer 10 is ready
The loop of 350 and S360 is repeated and waits. If the printer 10 is ready in step S360, print data is transmitted (step S370), and
Returning to step S330, the presence or absence of print data is checked.
This loop is repeated until there is no more data, and when all the print data has been transmitted, as described above, step S
At 400, the return code is set to "normal end" and this routine is ended.

FIG. 5 is a flowchart showing a printer power OFF routine. This routine is started when there is a "printer power off" request from the application or when the power of the electronic computer 30 is turned off. First, the output port P2 is set to the L level, and the printer 1
The power of 0 is turned off (step S610). The interrupt INTA is returned to the disabled state (step S620), ON
The flag 39b is returned to the L level voltage (step S63).
0). "Normal termination" is set as the return code (step S640), this routine is terminated, and the application program or the computer 30 is turned off again.

FIG. 6 is a flowchart showing the interrupt INTA processing routine. In this routine, after interruption is permitted in step S190 of the printer power ON routine of FIG. 3, step S of the printer power OFF routine of FIG.
Interrupt terminal INT until the interrupt is disabled at 620
This is a process executed when A becomes L level. First, an H level is written in the low battery flag 39a (step S670).
The printer 1 outputs an H level signal to the output port P1.
The generation of low battery is notified to the interrupt INTB terminal of 0, and this routine is once ended.

Next, the print control of the printer 10 will be described. FIG. 7 is a flowchart showing a print control routine of the printer 10. This routine is started immediately after the power is turned on and then started or by a reset. First, initial settings such as input / output ports are made (step S8).
10) Until the internal processing is completed, a busy signal is output (step S820). Interrupt terminal INT
It is checked whether B (which becomes an input port because the interrupt is disabled at this point) is at the H level (step S
840). As described above, when a low battery is generated, the port of the interrupt terminal INTB becomes L level by the low battery signal from the electronic computer 30. When the port of the interrupt terminal INTB is at the L level, the process proceeds to step S980, the LED display 17 displays "low battery", and the control line 23
The low battery is also output to c (step S980), and the occurrence of reset is awaited (step S990). After this, the remaining capacity of the battery 21a is exhausted and the battery 21a is reset, or the power is turned off by the power off signal from the electronic computer 30 and the supply of the internal power supply is stopped to be turned off. The reason why the power is not turned off immediately when the low battery signal is generated is to notify the user of the generation of the low battery also by the display on the printer side. Step S840
When the interrupt terminal INTB is at H level, the 1-bit low battery flag 16a assigned to the RAM 16 is cleared to L level (step S850). Register the interrupt INTB processing shown in FIG. 8 (step S860),
The interrupt INTB is permitted (step S870). After that, when the interrupt INTB is generated due to the generation of the low battery, the interrupt INTB processing of FIG. 8 is automatically executed.

Next, it is checked whether or not the low battery flag is at L level (step S890). When it is at the H level, it means that a low battery has been generated, and the reset waiting state is set in steps S980 and S990. When it is L level in step S890, it is checked whether or not there is any abnormality such as the presence or absence of printing paper (step S90).
0). If there is an abnormality, a display indicating the cause of the abnormality is displayed on the LED display 17 (step S1000), the content of the abnormality is output to the control line 23c, and the process returns to step S890. The process waits until the cause of abnormality is removed in the loop of steps S890, S900, and S1000. Step S90
If 0 indicates no abnormality, normal operation is displayed on the LED display 17 (step S910), no abnormality is output to the control line 23c, and a ready signal indicating that preparation for reception is completed is output (step S920). Next, it is checked whether or not there is print data (step S930).
When there is no print data, the process returns to step S890, and steps S890, S900, S910, S920, S9.
Repeat the process until 30 and print data arrive. If there is print data in step S930, step S94
At 0, the print data is fetched into the buffer 19a. In step S950, the print data for one line is stored in the buffer 19a.
It is checked whether or not it is stored (step S950). 1
When the print data for the line is not stored, the process returns to step S890, and steps S890, S900, S
The processing is repeated 910, S920, S930, S940, and S950 to wait until one line of print data is stored. When the print data for one line is stored in step S950, a busy signal indicating that the print data cannot be received because the print processing is performed (step S960), and the print processing is performed (step S960).
970). Again, the process returns to step S890 and the same processing is repeated. The printed data for one line is erased from the buffer 19a.

FIG. 8 is a flowchart showing the interrupt INTB processing routine. This processing is executed when the interrupt terminal INTB goes to L level and an interrupt signal is generated after the interrupt is permitted in step S870 of FIG. The H level is written in the low battery flag (step S1020), and this routine is once ended.

As described above, according to the information processing device 5 to which the power management device of the present embodiment is applied, even if the voltage of the battery 21a drops during the transmission of print data, the battery voltage will not drop. It is constantly monitored inside, and when the battery voltage drops, "low battery" is set to the return code and the print request routine ends, so the communication handshake collapses and the printer 10 and computer 30 stop and malfunction. Can be prevented.

Further, it is not necessary to wait until the print data is not transmitted until it times out. Further, in a state where the multi-core cable 23 is connected between the connectors 22 and 45, the printer 10 is connected from the computer 30 side.
Since the power ON / OFF control of the
Is unable to communicate with the printer 10, for example, when the computer 30 is powered off or the multi-core cable 23 is not attached, it is possible to avoid forgetting to turn off the power supply and perform detailed power management. You can

Furthermore, it is not necessary for both connected devices to have the same display function, and it is easy for the user to know the status of the other device that is connected to one of the connected power supplies. Also, the status can be known only from the display of one device that manages the power supply.

In this embodiment, the LE is installed on the printer 10 side.
Although the D display unit 17 is provided so that the power supply state can be displayed, even if the LED display unit 17 is not provided on the printer 10 side, only the electronic computer 30 side that manages the power supply can display the power supply state. May be.

[Second Embodiment] Next, a power management apparatus of a second embodiment will be described. However, the electric power management circuit of the second embodiment is different from that of the first embodiment only in the configurations of the power supply circuit 120 and the CPU 114, and other electrical configurations are different. Is the same. FIG. 9 shows a power supply circuit 120
3 is a circuit diagram showing the electrical configuration of FIG. The same parts as those in the first embodiment are designated by the same reference numerals. That is, the switching transistor 20e is provided in parallel with the switching transistor 20a. The output port P1 of the base input terminal CPU114 of the switching transistor 20e is connected, and when the CPU 114 sets the output port P1 to the H level, the switching transistor 20e is turned on. Here, the signal line 23a indicating the power ON / OFF
Since power is not supplied from the power supply circuit 120 to each part of the printer 10 until the printer 10 is turned on, the output port P1 of the CPU 114 is at the L level or in the high impedance state, so the switching transistor 20e is turned off. Is. In this state, when an H level ON signal is transmitted to the signal line 23a indicating the power ON / OFF, both the switching transistor 20a and the power transistor 20b are turned on as in the first embodiment, and the battery voltage of the battery 21a is increased. After the check is performed, the battery voltage of the battery 21a is applied to the power supply drive circuit 20c. After the power of the printer 10 is turned on, the switching transistor 20e is off when the output of the output port P1 is at L level, and the switching transistor 20a is turned on by the power on signal of the signal line 23a indicating power on / off. Then, the power transistor 20b is turned on and the battery voltage is maintained.

On the other hand, since the transistor 20e is turned on when the output of the output port P1 is at the H level, the power source O
The signal line 23a indicating N / OFF turns off the power at the L level
Even if the switching transistor 20a is a signal and the switching transistor 20a is off, the power transistor 20b is on, so that the battery voltage is maintained similarly. That is, after the power of the printer 10 is turned on, the output port P1 or the power is turned on.
The power transistor 20b is turned off only when the signal lines 23a indicating / OFF are both at the L level, and the supply of the battery voltage to the power supply drive circuit 20c is stopped. As a result, the printer 10 sets the output port P1 to the H level so that the power cannot be turned off when the power is turned off due to print data remaining in the print buffer or the like, and the print processing ends. Can be extended to. Even an electronic device that manages power supply can output a power-off signal without being aware of the processing state of the connection partner.

[Third Embodiment] A power management apparatus according to the third embodiment will be described below. FIG. 10 is a circuit diagram showing the electrical configuration of the power supply monitor circuit of this embodiment. Compared with the first embodiment, the power supply monitor circuit 149 of the electronic computer 130.
The other electrical configurations are the same except for the configuration of the CPU 137. The same parts as those in the first embodiment are indicated by the same numbers. A resistor 155 and a resistor 156 are connected as dummy loads to the power cable 23e to the transistors 153 and 154, respectively, so that dummy loads can be prepared for two systems. The base input terminals of the transistors 153 and 154 are CP
It is connected to the output ports P3 and P4 of U137, and C
The PU 137 can turn on / off the transistors 153 and 154 by selectively setting the output ports P3 and P4 to the H / L level. Transistors 155 and 15
By turning on and off 6, power cable 23e
Load is “only resistor 155”, “only resistor 156”, “parallel resistor of resistor 155 and resistor 156”,
Four dummy loads of "no load" can be selected. The power supply voltage is detected by comparing the voltage obtained by dividing the power supply cable 23e with the voltage dividing resistors 175 and 176 and the output voltage 152a of the analog multiplexer 152 into the comparator 15.
This is done by comparing in 1. The analog multiplexer 152 selects one of the four inputs X1 to X4 from the battery voltage input to the four terminals X1, X2, X3, and X by the combination of H / L of the selection terminals A and B, and outputs it to the COM terminal. Integrated circuit. Here, the INH terminal is a terminal to which a signal for controlling the presence / absence of the output is input, and by being grounded (GND), it is always output according to the selection of A and B. The stabilized internal operating voltage is applied to the voltage dividing resistors 183, 184, 1 at terminals X1 to X4.
The signals are divided by 85, 186 and 187 and input, and the output signals of the output ports P5 and P6 of the CPU 137 are input to the selection terminals A and B. As a result, the power cable 23e
Four reference voltages Vx1, Vx2, Vx3, Vx4 set by the resistors 183 to 187 for comparison with the battery voltage Va divided by the resistors 175 and 176 of FIG.
Can be selected according to the voltage of the output ports P5 and P6. The output of the comparator 151 is connected to the interrupt terminal INTA of the CPU 137, and the divided battery voltage Va of the power cable 23e is the selected reference voltage Vx1, Vx.
When it becomes lower than x2, Vx3, and Vx4, an L level signal is output to the interrupt terminal INTA to generate interrupt INTA processing.

The CPU 137 of the electronic computer 130 turns on the power of the equipment connected from the application program.
When a request to turn on is issued, the reference voltages Vx1, Vx2, Vx3, and Vx4 are output ports P5 and P according to the device.
6 output, and a dummy load corresponding to the device is selected by the output ports P3 and P4. When the dummy load is selected, the power of the device such as the printer 10 connected by the signal line 23a indicating the power ON / OFF is turned on. At this time, the output port P5,
The H / L setting of P6 remains unchanged until the application program requests power off. CPU13
In No. 7, when the interrupt terminal INTA becomes L level, the fact that the battery is a low battery is notified via the signal line 23b indicating the low battery signal, as in the first embodiment.

As described above, according to the power management device of the third embodiment, it is possible to support a plurality of types of connected devices with different power consumption.

[Fourth Embodiment] A power management apparatus according to the fourth embodiment will be described below. FIG. 11 shows a power supply monitor circuit 1
It is a circuit diagram which shows the electric constitution of 49. When the power management apparatus of the present embodiment detects a decrease in the battery voltage with the computer during the communication process with the printer, the process is continued by the battery voltage from the power cable on the printer side, and the process of the decrease in the battery voltage is performed after the process is completed. It was made to move to. Compared with the first embodiment, the power supply monitor circuit 149 and the CPU 2
It is configured only by changing the configuration of 37. The other parts that are the same as those in the first embodiment are designated by the same reference numerals.

The battery 5 which is the operating power source of the electronic computer 230
The output of 4a is a power transistor 205, a diode 2
It is connected to the input terminal of the power supply circuit 211 via 06. The switching transistor 209 that drives the power transistor 205 is connected to the ON / OFF control unit 202. The ON / OFF control unit 202 is provided with a switch 203, and the switch 203 is turned ON.
The output of the ON / OFF control unit 202 becomes H
The switching transistor 209 is turned on and the switching transistor 209 is turned on. Along with this, the battery voltage of the battery 54a is controlled by the power supply circuit 2 via the power transistor 205 and the diode 206.
11 is input.

The power supply circuit 211 constantly compares the voltage input through the power supply cable 207 with the preset reset voltage and low battery voltage. Here, the reset voltage is set to be smaller than the low battery voltage (reset voltage <low battery voltage). When the battery voltage input via the power cable 207 is lower than the low battery voltage, the signal line 21 indicating the low battery
3 is set to the L level and the interrupt terminal INTC of the CPU 237 is set.
To generate the interrupt INTC process, and when the voltage is lower than the reset voltage, the reset line 212 is set to the L level to reset the CPU 237.

The output port P7 of the CPU 237 is connected to the base input terminal of the switching transistor 210, and the switching transistor 210 is turned on to drive the power transistor 209 by setting the output port P7 to the H level. As a result, the battery voltage of the battery 21a connected to the power cable 23e on the printer 10 side is input to the power supply circuit 211 via the diode 208. Therefore, the power supply circuit 211 includes the printer 10
Side battery 21a and electronic computer 230 side battery 54a
Will be selectively powered. Here, the diodes 206 and 208 are diodes for preventing backflow so that no inflow occurs between the battery 21a on the printer 10 side and the battery 54a on the electronic computer 230 side.

When the in-process flag 39c is assigned to the RAM 39, it indicates that the in-process flag 39c is set to the H level during the communication process, and that the in-process flag 39c is set at the end of the communication process. Is set to L level. Also, the output port P7 is set to the L level. When the low battery signal is input to the CPU 237, the CPU 237 executes the interrupt INTC process.
In the interrupt INTC processing, first, the processing flag 39c is set to H.
Whether or not it is in the level is checked, and if it is not in the H level, normal low battery processing is performed. When it is H level, the INTC input port confirms that the output port P7 is set to H level and the signal line 213 indicating the low battery is switched to H level. If not switched to the H level, the output port P7 is returned to the L level and the low battery processing is performed as it is. When the H level is reached, the interrupt process is terminated and the printing process is continued. If a low battery is generated at the time when the printing process ends and the in-process flag 39c is set to the L level and the output port is set to the L level, the low battery process is performed.

As described above, when the remaining capacity of the battery 54a is small and the battery voltage becomes low and becomes lower than the low battery voltage, the signal line 213 indicating the low battery is L.
When the interrupt INTC processing is performed when the level becomes the level, the output port P7 is set to the H level and the battery 21 of the printer 10 side is set.
Since the voltage of a is supplied to the power supply circuit 211 and the electronic computer operates on the battery 21a of the printer 10, the processing of the electronic computer that manages the power supply of the printer can be surely ended. Further, when the connected device is a printer, it is possible to print that the low battery voltage is generated and record it in a record.

[Fifth Embodiment] FIG. 12 is a block diagram showing the electrical construction of an information processing apparatus to which the power management apparatus of the fifth embodiment is applied. The information processing apparatus 510 of this embodiment is C
The PU 517, the display device 521, the keyboard 524, the main memory 526, the counter 528, the timer 536, and the battery 541 are provided via the bus 543. The power of the counter 528 is backed up by a dedicated battery 528a of the counter. The counter 528 stores the number of interrupts. A control program is stored in the main memory 526. A power supply line 545 is connected to each part of the main battery 541 except the counter 528. Counter 52
8 has a small storage capacity of 2 bytes, and the dedicated battery 528a used therein has low power consumption, so that a normal alkaline battery can be used.

The operation of the information processing apparatus of this embodiment will be described. FIG. 13 is a flowchart showing the keyboard interrupt routine. This routine is executed by a keyboard interrupt. That is, it is executed when any key is input. Here, the zero clear for setting the count value of the counter 528 to “0” can be performed at any time by the user of this device, but normally it is performed when the battery is replaced or immediately after recharging. Zero-clear is done by pressing the two keys "CTRL" and "I" of the keyboard 524 at the same time. First, "CTRL"
It is determined whether or not the two keys "1" and "I" have been pressed simultaneously (step S510). When the above two keys are pressed at the same time, the CPU 517 writes the value "0" in the counter 528 (step S520), and once ends this routine.

The timer 536 generates a timer interrupt signal at regular intervals (1 second in this embodiment) immediately after the power is turned on. The counter 528 increments the count value by the timer interrupt signal, but since its storage capacity is 2 bytes, it can count 64K seconds (about 17 to 18 hours). Considering the current battery life of computers, it is sufficient to count such time. Since the power source of the counter 528 is always backed up by the dedicated battery 528a, even if the power of the main body is turned off, the count value as the energization time is stored with an error within 1 second.

FIG. 14 is a flowchart showing the timer interrupt routine. When a timer interrupt occurs every one second, the CPU 517 reads the value of the counter 528 (step S610), increments the count value (step S620), and then writes the value again in the counter 528 (step S630), and this routine is once ended. .

The CPU 517 is called "CTR" by the user.
It is determined whether or not the two keys "L" and "T" are pressed simultaneously (step S530), and the count value of the counter 528 is read by pressing these two keys at the same time (step S540). The count value is converted into hours, minutes, and seconds and displayed on the display device 521, and this routine is once ended (step S550). As a result, the user can always know the accumulated energization time. When another key is pressed, normal key input processing is executed (step S570).

As described above, the total energization time is recognized by the two keys "CTRL" and "T" immediately before the battery replacement or recharge, and the count value is recognized by the two keys "CTRL" and "I". Is reset to "0". By performing such an operation many times, the user can know the average energization time until the battery is replaced or recharged. Therefore, if you are worried about running out of battery during use, "C
The current remaining capacity can be grasped by reading the time with "TRL" and "T" and comparing it with the average energization time. Therefore, it is possible to take measures such as charging when there is time in advance. The counter 528 may be replaced with RAM.

[Sixth Embodiment] Next, a power management apparatus of a sixth embodiment will be described. FIG. 15 is a block diagram showing the electrical configuration of the power management device of the sixth embodiment. The power management device 610 of the present embodiment is configured by adding an AC (alternating current) external power supply 611 and a power supply discriminating device 615 to the fifth embodiment. The same parts as those in the fifth embodiment are designated by the same reference numerals. The AC external power supply 611 has a configuration for charging the battery 541 during use. The CPU 517 determines whether the main body is driven by the battery 541 or the AC (alternating current) external power source 611 by the power source determining device 615, and determines the drive time during which the main body is driven by the AC external power source 611 in the fifth embodiment. The same process as in (1) is performed without integrating the energization time. FIG. 15 is a flowchart showing the timer interrupt processing routine. Whether the battery 541 or the AC external power supply 611 is used is determined by the power supply discriminating device 615 (step S705), and only when the battery is driven, the same process as steps S610 to S630 of the fifth embodiment is performed to determine the count value. Increment (steps S710 to S730). When the AC power supply is being driven, this routine is ended without incrementing the count value.

As described above, energization with a high utility value is achieved by simply providing a timer interrupt processing routine and a dedicated battery for backing up the power of the counter without changing the dedicated hardware, without providing dedicated hardware. The time can be displayed.

[0050]

According to the power management apparatus of the present invention, each electronic device is equipped with a battery having a capacity corresponding to its power consumption, and one electronic device manages the power supply of the other electronic device. Therefore, it is not necessary to provide a power switch and its display on both electronic devices. Also, it is not necessary to check the power supplies of both sides. in this way,
When one electronic device manages the power supply of the other electronic device, even if there is a power consumption imbalance between the electronic devices, it is not necessary to install an excessive battery in only one electronic device.

Also, since the power supply of both electronic devices that are communicating is managed by one electronic device, only one electronic device unilaterally interrupts communication due to a decrease in battery voltage. Can be prevented.

Furthermore, since the energization time of the battery-driven electronic equipment can be known from the number of interrupt signals stored in the counter, existing hardware such as a counter can be used without providing dedicated hardware. It is possible to display the energization time with high utility value.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an electrical configuration of an information processing device 5 to which a power management device of a first embodiment is applied.

2 is a circuit diagram showing an electrical configuration of an interface portion between the printer 10 and the electronic computer 30. FIG.

FIG. 3 is a flowchart showing a printer power ON routine.

FIG. 4 is a flowchart showing a print request routine.

FIG. 5 is a flowchart showing a printer power OFF routine.

FIG. 6 is a flowchart showing an interrupt INTA processing routine.

FIG. 7 is a flowchart showing a print control processing routine.

FIG. 8 is a flowchart showing an interrupt INTB processing routine.

FIG. 9 is a circuit diagram showing an electrical configuration of a printer-side power supply circuit 120 to which the power management device of the second embodiment is applied.

FIG. 10 is a circuit diagram showing an electrical configuration of a power supply monitor circuit 149 of the electronic computer 130 to which the power supply management device of the third embodiment is applied.

FIG. 11 is a circuit diagram showing an electrical configuration of a power supply monitor circuit 149 to which the power supply management device of the fourth embodiment is applied.

FIG. 12 is a block diagram showing an electrical configuration of an information processing device 510 to which the power management device of the fifth embodiment is applied.

FIG. 13 is a flowchart showing a keyboard interrupt routine.

FIG. 14 is a flowchart showing a timer interrupt routine.

FIG. 15 is a block diagram showing an electrical configuration of an information processing device 510 to which the power management device of the sixth embodiment is applied.

FIG. 16 is a flowchart showing a timer interrupt routine.

[Explanation of symbols]

 5 ... Information processing device 10 ... Printer 20 ... Power supply circuit 30 ... Computer 49 ... Power supply monitor circuit

Claims (7)

[Claims] 1. A first electronic device having a battery as a power source is a second electronic device.
Is connected to the electronic device, the second electronic device is a power management device that manages the power supply of the first electronic device, and the second electronic device controls the battery voltage of the first electronic device. Battery voltage detection means for detecting, and when the power supply of the first electronic device is in the on state,
Comparing means for comparing the battery voltage detected by the battery voltage detecting means with a predetermined value, and switching for turning off the power source of the first electronic device by the comparing means when the battery voltage is less than or equal to the predetermined value. A power management device having means. 2. The second electronic device includes connecting means for connecting the battery of the first electronic device to a load that is a dummy of the first electronic device, and connecting the battery to the battery by the connecting means. Load voltage detection means for detecting whether or not the voltage of the loaded load exceeds a predetermined value, the switching means includes power-on means for turning on the power supply of the first electronic device, and the load voltage 2. The power management apparatus according to claim 1, wherein the power-on means turns on the power supply of the first electronic device when the voltage of the load exceeds a predetermined value by the detection means. 3. The switching means transfers a decrease in the battery voltage by the comparing means to the first electronic device, and the power supply of the first electronic device according to the transfer by the transferring means. A power source for turning off the power source by the power source turning off means for a predetermined period after the battery voltage drop is transmitted by the transmitting means. 3. The power management device according to claim 1, further comprising an OFF invalidating unit. 4. The second electronic device connects the load connected by the connecting means to the first electronic device.
A first selecting means for selecting from a plurality according to the capacity of the battery of the electronic device, and a first selecting means for selecting the predetermined value according to the load selected by the first selecting means from the plurality. 3. The power management device according to claim 2, further comprising: two selection means. 5. The first electronic device and the second electronic device each have a first battery and a second battery as power sources, and a battery voltage of the second battery of the second electronic device. A second battery voltage detecting means for detecting that the battery voltage is below a predetermined value, and when detected by the second battery voltage detecting means,
The power management device according to claim 1, further comprising a switching unit that switches the first battery to a power source of the second electronic device. 6. A control circuit that uses a battery as a power source, and a switch circuit that turns on and off the power source, the control circuit generating an interrupt signal of a constant cycle during energization after the power source is turned on by the switch circuit. A signal generating circuit, a counter that stores the number of interrupt signals generated by the interrupt signal generating circuit, and a display circuit that displays the energization time based on the number of interrupt signals stored in the counter. Power management device for electronic devices. 7. The power management device according to claim 6, further comprising a second battery, wherein the counter is constantly energized by the second battery.