Printer

Abstract

To provide a printer which can secure power required for printing, even if a residual amount of a battery varies after power feeding to an external device is started.SOLUTION: A printer can be driven by a battery. The printer includes a printing part, a power feeding part and a USBPDIC. The printing part can execute printing on a medium, on the basis of power of the battery. The power feeding part can feed power to be fed which is power to be fed on the basis of the power of the battery, to an external device. The USBPDIC monitors a residual amount of the battery, after power feeding of the power to be fed to the external device by the power feeding part is started (S9). The USBPDIC changes the power to be fed to the external device, according to the residual amount of the monitored battery (S11).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a printer. [Background technology]

[0002] The power transmission device in Patent Document 1 is driven by a battery. The power transmission device determines the feed power, which is the power to be fed to the power receiving device, based on the power of the battery. The power transmission device feeds the determined feed power to the power receiving device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-127933 A Summary of the Invention [Problem to be solved by the invention]

[0004] The power transmitting device continues to supply power at the determined supply power even when the remaining battery charge is low. In this case, depending on the remaining battery charge, there is a possibility that the power required for the power transmitting device may be insufficient.

[0005] An object of the present invention is to provide a printer that can ensure the power required for printing even if the remaining battery level changes after power supply to an external device begins. [Means for solving the problem]

[0006] The printer of the present invention is a battery-powered printer and includes a printing unit capable of printing on a medium based on the power of the battery, a power supply unit capable of supplying supply power to an external device, which is power supplied based on the power of the battery, and a control unit, wherein the control unit executes a monitoring process that monitors the remaining charge of the battery after the power supply unit starts supplying the supply power to the external device, and a change process that changes the supply power to the external device depending on the remaining charge of the battery monitored by the monitoring process.

[0007] The printer can appropriately control the supply of power to the external device by changing the supply power in response to fluctuations in the remaining battery charge. Therefore, the printer can ensure the power required for printing even if the remaining battery charge fluctuates after the printer starts supplying power to the external device. The printer can appropriately control the supply of power to the external device by changing the supply power in response to fluctuations in the remaining battery charge. Therefore, the printer can ensure the power required for printing even if the remaining battery charge fluctuates after the printer starts supplying power to the external device.

[0008] In the present invention, the change process may reduce the supply power in response to a decrease in the remaining battery charge monitored by the monitoring process. By reducing the supply power in response to a decrease in the remaining battery charge, the printer can ensure power required for printing while also ensuring power supply to external devices.

[0009] In the present invention, the battery may be charged by power from an external power source, and the change process may increase the supply power in accordance with an increase in the remaining battery power monitored by the monitoring process while the battery is being charged by power from the external power source. When the remaining battery power increases due to charging, the printer can increase the supply power to external devices while ensuring the power necessary for printing.

[0010] In the present invention, the change process may include stopping the supply of power to the external device when the remaining charge of the battery is less than a threshold value. By stopping the supply of power to the external device, the printer can secure power necessary for printing.

[0011] In the present invention, the power supply unit may execute negotiation with the external device in accordance with the USB PD (USB Power Delivery) standard and supply the power to the external device based on a result of the negotiation. The printer can supply power to the external device in accordance with the USB PD (USB Power Delivery) standard.

[0012] In the present invention, the printer may further include a storage unit that stores a PDO (Power Data Object) indicating the power supply that the power supply unit can supply according to the remaining charge of the battery, and the change process may change the power supply to the power supply that corresponds to the remaining charge of the battery by referring to the PDO (Power Data Object) stored in the storage unit. The printer can control the supply of power in more detail by the PDO (Power Data Object).

[0013] In the present invention, the printer may further include a power supply path switching unit that switches a power supply path to the external device depending on whether an external power source is connected, and the power supply path switching unit may switch the power supply path so that power is supplied from the external power source when the external power source is connected. When the external power source is connected, the printer supplies power to the external device from the power of the external power source. [Brief description of the drawings]

[0014] [Figure 1] 2 is a diagram showing a connection state between a printer 1 and a tablet PC 5. FIG. [Diagram 2] 2 is a block diagram showing the electrical configuration of the printer 1. FIG. [Diagram 3] 13 is a flowchart of a main process. [Figure 4] 1 is a diagram showing PDO (Power Data Object). [Diagram 5] 13 is a flowchart of a main process in a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] An embodiment of the present invention will be described with reference to the drawings. The right-downward direction, the left-upward direction, the right-upward direction, the left-downward direction, the upper direction, and the lower direction in Fig. 1 correspond to the right, left, rear, front, upper, and lower directions of a printer 1, respectively.

[0016] As shown in FIG. 1, the printer 1 is configured to be capable of printing on a print medium. The medium is, for example, a plurality of thermal labels continuously affixed to a long backing paper. The printer 1 is driven by receiving power from a battery 11. The battery 11 is detachably mounted in a mounting section 42 (see FIG. 2) provided inside the printer 1. The battery 11 is, for example, a lithium ion secondary battery. The printer 1 can be driven by receiving power from an external power source connected to, for example, a commercial outlet (not shown). The external power source is, for example, an AC adapter 9 (see FIG. 2). The AC adapter 9 is connected to a mounting section 41 provided at the rear lower part of the right side of the printer 1.

[0017] An interface 43 is provided at the front lower part of the right side of the printer 1. The interface 43 is a USB interface (I / F) that complies with the USB Type-C (registered trademark) standard. A cable 3 is connected to the interface 43. The cable 3 has a connector that complies with the USB Type-C standard and supports USB PD (USB Power Delivery). For example, the cable 3 can transmit power corresponding to a current of up to 5A and transmit various information.

[0018] The printer 1 can be connected to, for example, an external device via the interface 43 and the cable 3. The external device is, for example, a tablet PC 5. The tablet PC 5 is equipped with, for example, an LCD touch panel. A user edits print data such as characters and figures on the touch panel, and transmits the print data to the printer 1 via the cable 3. The printer 1 prints characters such as characters and figures on a medium based on the print data received from the external device.

[0019] Furthermore, the printer 1 is capable of supplying power to the tablet PC 5 in accordance with the USB PD (USB Power Delivery) standard, thereby enabling the printer 1 to charge the tablet PC 5.

[0020] The electrical configuration of the printer 1 will be described with reference to Fig. 2. The printer 1 further includes a charging IC 31, an OR circuit 32, DCDC power sources 33 and 35, a digital circuit unit 6, a printing unit 7, and a power supply unit 8. The charging IC 31 charges the battery 11 attached to the attachment unit 42 based on power from an AC adapter 9. The battery 11 includes a sensor 11A capable of detecting the remaining battery charge. The output result from the sensor 11A is transmitted to the CPU 21. The CPU 21 detects the remaining charge of the battery 11 from the received output result.

[0021] The OR circuit 32 switches the power supply path to the tablet PC 5 depending on whether the battery 11 and the AC adapter 9 are connected. For example, when only the AC adapter 9 is connected, the OR circuit 32 switches the power supply path to supply power from the AC adapter 9. For example, when only the battery 11 is connected, the OR circuit 32 switches the power supply path to supply power from the battery 11. When the AC adapter 9 and the battery 11 are connected, for example, the OR circuit 32 switches the power supply path to supply power from the battery 11 to the digital circuit unit 6, the printing unit 7, the power supply unit 8, etc. while supplying power from the AC adapter 9 to the battery 11. Note that when the battery 11 and the AC adapter 9 are connected to the printer 1, the OR circuit 32 may switch the power supply path to supply power from the AC adapter 9 to the battery 11 and to supply power from the AC adapter 9 to the tablet PC 5. In this case, the OR circuit 32 may switch the power supply path to supply power from either the battery 11 or the AC adapter 9 to the digital circuit unit 6, the printing unit 7, the power supply unit 8, etc. The power supply path of the OR circuit 32 is switched automatically, but may be set by the user.

[0022] The DCDC power supply 33 converts the input voltage from the AC adapter 9 or the battery 11 into an output voltage (e.g., 3.3 V) for driving the digital circuit unit 6. The digital circuit unit 6 includes a CPU 21, a RAM 22, a flash memory 23, and an EEPROM 24. The CPU 21 performs overall control of the printer 1. The CPU 21 is electrically connected to the RAM 22, the flash memory 23, the EEPROM 24, the printing unit 7, and the power supply unit 8.

[0023] The RAM 22 temporarily stores various data such as print data received from the tablet PC 5. The flash memory 23 stores various programs executed by the CPU 21 and the USB PDIC 37 to control the printer 1. The EEPROM 24 stores information such as printer settings and print history.

[0024] Power from the AC adapter 9 or the battery 11 is supplied to the printing unit 7. The printing unit 7 is capable of printing on a medium based on the power of the AC adapter 9 or the battery 11. The printing unit 7 includes a thermal head 13 and a transport motor 15. The thermal head 13 generates heat in response to a signal from the CPU 21 and prints on the medium. The transport motor 15 drives a feed roller for feeding the medium. The CPU 21 controls the thermal head 13 and the transport motor 15 to print on the medium.

[0025] The power supply unit 8 includes a DCDC power supply 35, a USBPDIC 37, a FET 36, and an interface 43. The DCDC power supply 35 converts an input voltage from the AC adapter 9 or the battery 11 into an output voltage (e.g., 9V, 5V, etc.) suitable for supplying power to the tablet PC 5. Hereinafter, the power output by the DCDC power supply 35 is also referred to as "supplied power". The supplied power is supplied to the tablet PC 5. The USBPDIC 37 can communicate with the CPU 21. The USBPDIC 37 can control the value of the output voltage from the DCDC power supply 35. The USBPDIC 37 executes negotiation with the tablet PC 5 via the interface 43 in accordance with the USB PD (USB Power Delivery) standard. The USBPDIC 37 controls the supply of power from the DCDC power supply 35 to the tablet PC 5 by controlling the on / off of the FET 36. For example, when the FET 36 is turned on, the supplied power is supplied to the tablet PC 5 via the interface 43 and the cable 3. That is, the power supply unit 8 can supply power, which is power supplied based on the power of the AC adapter 9 or the battery 11, to the tablet PC 5. The USB PDIC 37 includes a storage unit 37A and the like. For example, the storage unit 37A stores a PDO (Power Data Object) described later.

[0026] The main processing will be described with reference to FIG. 3. In the following description, the case where the AC adapter 9 is not connected to the printer 1 will be described separately from the case where it is connected. First, the case where the AC adapter 9 is not connected to the printer 1 will be described. In this case, the printer 1 is driven only by the power of the battery 11. Since the AC adapter 9 is not connected, the printer 1 does not charge the battery 11. When the user presses the power button of the printer 1, the USBPDIC 37 reads and executes a program from the flash memory 23. This causes the USBPDIC 37 to start the main processing.

[0027] When the main process starts, the USBPDIC 37 determines whether or not to start negotiation with the tablet PC 5 (S1). For example, when the USBPDIC 37 detects that the tablet PC 5 is connected to the printer 1, it determines to start negotiation. When it determines not to start negotiation (S1: NO), the USBPDIC 37 returns to the process and waits. When it determines to start negotiation (S1: YES), the USBPDIC 37 executes negotiation with the tablet PC 5 (S3).

[0028] The USBPDIC 37 determines whether the negotiation has been successful (S5). For example, the USBPDIC 37 determines whether the negotiation has been successful based on whether the power supply unit 8 can supply the power requested by the tablet PC 5. If it is determined that the negotiation has failed (S5: NO), the USBPDIC 37 sets the power supply unit 8 to disable supply of power to the tablet PC 5 (S19). In this case, the USBPDIC 37 turns off the FET 36. This disables supply of power from the DCDC power supply 35. The USBPDIC 37 returns the process to S1.

[0029] If it is determined that the negotiation has been successful (S5: YES), the USBPDIC 37 starts supplying power from the power supply unit 8 to the tablet PC 5 (S7). In this case, the USBPDIC 37 turns on the FET 36. This causes power to be supplied from the DCDC power supply 35 to the tablet PC 5. For example, the power supplied in the process of S7 corresponds to the power requested by the tablet PC 5 in the negotiation executed in the process of S3. The USBPDIC 37 also controls the DCDC power supply 35 so that the voltage value requested by the tablet PC 5 is output. The USBPDIC 37 supplies power to the tablet PC 5 based on the result of the negotiation.

[0030] After the power supply unit 8 starts supplying power to the tablet PC 5, the USBPDIC 37 monitors the remaining charge of the battery 11 (S9). In this case, the USBPDIC 37 acquires the remaining charge of the battery 11 from the CPU 21. Note that the USBPDIC 37 may monitor the remaining charge of the battery 11 by directly acquiring the detection result of the sensor 11A.

[0031] The USBPDIC 37 changes the power supply to the tablet PC 5 according to the monitored remaining amount of the battery 11 (S11). In this case, the USBPDIC 37 refers to a PDO (Power Data Object) shown in FIG. 4. The PDO (Power Data Object) indicates the power supply that the power supply unit 8 can supply according to the remaining amount of the battery 11. The PDO (Power Data Object) classifies the power supply (voltage, current) corresponding to the remaining amount of the battery 11 into "PDO 0" to "PDO 4". According to the PDO (Power Data Object), as the remaining amount of the battery 11 decreases, the power supply that the power supply unit 8 can supply is restricted. For example, when the remaining amount of the battery is between 80% and 100%, the USBPDIC 37 can select the classification "PDO 0" to "PDO 4". In this case, the power supply unit 8 can supply a maximum of 27 W of power. On the other hand, when the remaining battery charge is between 0% and 20%, the USBPDIC 37 can select only the classification "PDO 4." In this case, the power supply unit 8 can supply a maximum power of 5 W.

[0032] The USBPDIC 37 starts negotiation with the tablet PC 5 based on the power supply changed in S11 (S13). The USBPDIC 37 determines whether the negotiation has been successful through communication with the power supply unit 8 (S15). If it is determined that the negotiation has been successful (S15: YES), the USBPDIC 37 starts supplying the power supply changed in the process of S11 (S17). The USBPDIC 37 returns the process to S9.

[0033] For example, in the process of S17, if the power supply started in the process of S7 can be continued, the power supply is maintained. For example, if the power supply (15 W) corresponding to the classification "PDO 1" has been supplied from the start of power supply to the tablet PC 5, the USBPDIC 37 will maintain the setting of the classification "PDO 1". Therefore, the power supply unit 8 maintains the supply of the power equivalent to 15 W in the process of S17.

[0034] On the other hand, assume that the power supply (15 W) corresponding to "PDO 1" is being supplied when the supply of power starts in the process of S7. Here, if the remaining charge of the battery 11 of the printer 1 is determined to be between 40% and 60% by monitoring in S9, the USBPDIC 37 sets the classification to "PDO 2". Accordingly, the power supply unit 8 becomes capable of supplying power equivalent to 10 W. The power supply is also set in the same manner when the remaining charge of the battery 11 is between 20% and 40%, or between 0% and 20%. In other words, the power supply unit 8 reduces the power supply in accordance with the decrease in the remaining charge of the battery 11 that is being monitored.

[0035] On the other hand, if it is determined that the negotiation has failed (S15: NO), for example, if it is determined that the power supply requested by the tablet PC 5 cannot be supplied, the USBPDIC 37 sets the supply of power from the power supply unit 8 to the tablet PC 5 to be disabled (S19). In this case, the USBPDIC 37 turns off the FET 36. The USBPDIC 37 returns the process to S1.

[0036] Next, a case where the AC adapter 9 is connected to the printer 1 will be described. In this case, the battery 11 is charged with power from the AC adapter 9. Therefore, the remaining charge of the battery 11 increases over time. Note that power is supplied from the battery 11 to the digital circuit unit 6, the printing unit 7, the power supply unit 8, etc.

[0037] As shown in FIG. 3, the USBPDIC 37 executes the processes of S1 to S5, S7, and S19 in the same manner as described above. The USBPDIC 37 monitors the remaining capacity of the battery 11 (S9). The USBPDIC 37 changes the power supply to the tablet PC 5 according to the monitored remaining capacity of the battery 11 (S11). In this case, the USBPDIC 37 refers to the PDO (Power Data Object) shown in FIG. 4 and increases the power supply according to an increase in the monitored remaining capacity of the battery 11. For example, when the remaining capacity of the battery 11 increases from 20% to 40% (classification "PDO 3") to 40% to 60% (classification "PDO 2"), the USBPDIC 37 can increase the power supply from 7.5 W (classification "PDO 3") to 10 W (classification "PDO 2").

[0038] Thereafter, the USBPDIC 37 executes the processes of S13 to S17 and S19. The processes of S13 to S17 and S19 are the same as those when the AC adapter 9 is not connected to the printer 1.

[0039] As described above, after the power supply unit 8 starts supplying power to the tablet PC 5, the USBPDIC 37 monitors the remaining charge of the battery 11. The USBPDIC 37 changes the power supply to the tablet PC 5 according to the monitored remaining charge of the battery 11.

[0040] The printer 1 can appropriately control the power supply to the tablet PC 5 by changing the power supply in response to fluctuations in the remaining charge of the battery 11. Therefore, the printer 1 can secure the power necessary for printing even if the remaining charge of the battery 11 fluctuates after starting to supply power to the tablet PC 5.

[0041] The USBPDIC 37 reduces the power supply in accordance with the monitored decrease in the remaining charge of the battery 11. By reducing the power supply in accordance with the decrease in the remaining charge of the battery 11, the printer 1 can ensure the power required for printing while ensuring the power supply to the tablet PC 5.

[0042] The battery 11 is charged by power from the AC adapter 9. When the battery 11 is being charged by power from the AC adapter 9, the USBPDIC 37 increases the power supply in accordance with an increase in the monitored remaining charge of the battery 11. When the remaining charge of the battery 11 increases due to charging, the printer 1 can increase the power supply to the tablet PC 5 while ensuring the power required for printing.

[0043] The power supply unit 8 executes negotiation in accordance with the USB PD (USB Power Delivery) standard with the tablet PC 5. Based on the result of the negotiation, the power supply unit 8 supplies power to the tablet PC 5. The printer 1 can supply power to the tablet PC 5 in accordance with the USB PD (USB Power Delivery) standard.

[0044] The storage unit 37A stores a PDO (Power Data Object) that indicates the power supply that the power supply unit 8 can supply according to the remaining charge of the battery 11. The USBPDIC 37 refers to the PDO (Power Data Object) stored in the storage unit 37A and changes the power supply according to the remaining charge of the battery 11. The PDO (Power Data Object) allows the printer 1 to control the supply of power in more detail.

[0045] The OR circuit 32 switches the power supply path to the tablet PC 5 depending on whether the AC adapter 9 is connected or not. When the AC adapter 9 is connected, the OR circuit 32 switches the power supply path so that power is supplied from the AC adapter 9. Therefore, when the AC adapter 9 is connected, the printer 1 can supply power to the tablet PC 5 from the power of the AC adapter 9.

[0046] The main processing in the modified example will be described with reference to Fig. 5. In the above embodiment, the power supply is determined based on the remaining charge of the battery 11 and with reference to the PDO (Power Data Object) shown in Fig. 4. In contrast, the main processing in the modified example differs in that the possibility of power supply is changed based on the relationship between the remaining charge of the battery 11 and a predetermined threshold without reference to the PDO (Power Data Object).

[0047] When the main process starts, the USBPDIC 37 judges whether or not to start negotiation with the tablet PC 5 (S101). For example, if the tablet PC 5 is not connected and it is judged not to start negotiation (S101: NO), the USBPDIC 37 returns to the process and waits. If the tablet PC 5 is connected and it is judged to start negotiation (S101: YES), the USBPDIC 37 executes negotiation with the tablet PC 5 (S103).

[0048] The USBPDIC 37 judges whether the negotiation has been successful (S105). If it is judged that the negotiation has failed (S105: NO), the USBPDIC 37 disables the supply of power from the power supply unit 8 (S115). In this case, the USBPDIC 37 turns off the FET 36.

[0049] If it is determined that the negotiation is successful (S105: YES), the USBPDIC 37 starts supplying power to the tablet PC 5 in accordance with the result of the negotiation (S107). In this case, the power supply unit 8 supplies power in accordance with the request of the tablet PC 5.

[0050] The USBPDIC 37 monitors the remaining charge of the battery 11 (S109). The USBPDIC 37 determines whether the monitored remaining charge of the battery 11 is equal to or greater than a predetermined threshold (S111). Here, the threshold is, for example, 30% of the maximum remaining charge of the battery 11. Note that the user may change the threshold as appropriate depending on the desired printing speed.

[0051] When it is determined that the remaining charge of the battery 11 is equal to or greater than the threshold (S111: NO), the USBPDIC 37 continues to supply power to the tablet PC 5 (S113). The USBPDIC 37 returns the process to S109. On the other hand, when the remaining charge of the battery 11 is less than the threshold (S111: NO), the USBPDIC 37 sets the power supply unit 8 to disable the supply of power to the tablet PC 5 (S115). The USBPDIC 37 returns the process to S101.

[0052] Therefore, the printer 1 can secure the power required for printing by stopping the supply of power to the tablet PC 5.

[0053] The present invention is not limited to the above-described embodiment, and various modifications are possible. The techniques disclosed in the above-described embodiment and modified examples can be combined to the extent that they are not inconsistent. The printer 1 is a thermal printer, but is not limited to this, and may be an inkjet printer. The external device is a tablet PC 5, but is not limited to this. For example, the external device may be a smartphone or a PC or other device. The AC adapter 9 is used as the external power source, but is not limited to this. For example, the external power source may be a battery or the like. The printer 1 may receive power from the external device in accordance with the USB PD (USB Power Delivery) standard.

[0054] In the above embodiment, the power supply power is changed by referring to the PDO (Power Data Object) shown in Fig. 4, but this is not limited to the above. The number of categories may be set to be smaller or larger depending on the remaining capacity of the battery 11. In addition, the set value of each category may be changed as appropriate.

[0055] In the above embodiment, the power supply requested by the external device is supplied in S7 and S107 in the main process, but this is not limited to the above. For example, the remaining capacity of the battery 11 may be monitored before the process of S1, and the power supply according to the remaining capacity may be supplied by referring to the PDO (Power Data Object).

[0056] In the above embodiment, the PDO (Power Data Object) is stored in the storage unit 37A of the USB PDIC 37, but this is not limiting. For example, the PDO (Power Data Object) may be stored in another storage medium such as the flash memory 23, the EEPROM 24, etc.

[0057] Instead of the USBPDIC 37, a CPU, an ASIC, an FPGA (Field Programmable Gate Array), or the like may be used as a processor. Each main process may be distributed among a plurality of processors. The printer 1 may include other non-transitory storage media, such as a HDD. The non-transitory storage medium may be any storage medium capable of retaining information regardless of the period for which the information is stored. The non-transitory storage medium may not include a temporary storage medium (e.g., a transmitted signal).

[0058] The various programs may be downloaded (i.e., transmitted as a transmission signal) from a server connected to a network (not shown) and stored in a memory such as a HDD. In this case, the various programs may be stored in a non-transitory storage medium such as a HDD provided in the server.

[0059] In the above description, the USBPDIC 37 is an example of a "control unit" of the present invention. The AC adapter 9 is an example of an "external power supply" of the present invention. The tablet PC 5 is an example of an "external device" of the present invention. The OR circuit 32 is an example of a "power supply path switching unit" of the present invention. The processes of S9 and S109 performed by the USBPDIC 37 are an example of a "monitoring process" of the present invention. The processes of S11 and S111 performed by the USBPDIC 37 are an example of a "changing process" of the present invention. [Explanation of symbols]

[0060] 1. Printer 5. Tablet PC 7 Printing Department 8 Power supply unit 9 AC adapter 11 Battery 37 USBPDIC 37A Memory Department

Claims

1. A battery-powered printer, a printing unit capable of printing on a medium based on the power of the battery; a power supply unit capable of supplying power, which is power supplied based on the power of the battery, to an external device; Control unit and Equipped with The control unit is a monitoring process of monitoring a remaining amount of the battery after the power supply unit starts supplying the power to the external device; a change process of changing the power supply to the external device according to the remaining charge of the battery monitored by the monitoring process; Run A printer characterized by:

2. The change process includes: The power supply is reduced in response to a decrease in the remaining charge of the battery monitored by the monitoring process.

2. The printer according to claim 1.

3. The battery is charged by power from an external power source; The change process includes: When the battery is being charged with power from the external power source, the supply power is increased according to an increase in the remaining charge of the battery monitored by the monitoring process.

2. The printer according to claim 1.

4. The change process includes: When the remaining charge of the battery is less than a threshold, the supply of the power to the external device is stopped.

2. The printer according to claim 1.

5. The power supply unit includes: Executing a negotiation with the external device in accordance with the USB PD (USB Power Delivery) standard; Based on a result of the negotiation, the external device is supplied with the power.

2. The printer according to claim 1.

6. A storage unit that stores a power data object (PDO) indicating the power supply that can be supplied by the power supply unit according to a remaining charge of the battery, The change process includes: The power supply power is changed according to the remaining charge of the battery by referring to the PDO (Power Data Object) stored in the storage unit.

6. The printer according to claim 5.

7. a power supply path switching unit that switches a power supply path to the external device depending on whether an external power source is connected, The power supply path switching unit is When the external power source is connected, the power supply path is switched so that power is supplied from the external power source.

2. The printer according to claim 1.

Images