BACKGROUND
The present invention relates to a control method for a printer
that changes between two operating states that consume different
amounts of power, and to a printer.
2. Related Art
[0002]
Japanese Unexamined Patent Appl. Pub. JP-A-H08-142458 discloses
a printer that changes from a normal operating mode in which the
printing operation can be performed to a power conservation mode that
consumes less power than the normal operating mode when print data
is not supplied from an external device for a specific time, or a
switch is not operated by the user for a specific time. When the
operating state of the disclosed printer changes from the normal
operating mode to the power conservation mode, supplying power to the
display device that displays status information also stops.
[ 0 0 04]
When a switch is operated and input is received in the power
conservation mode by a printer that changes the operating state
between the normal operating mode and power conservation mode, the
printer returns the operating state to the operating mode and then
executes the operation invoked by the input received from the switch.
[0005]
With the printer disclosed in JP-A-H08-142458, the power supply
to the display unit stops when the power conservation mode is entered,
and the user is unable to determine the status of the printer. As a
result, because the user must operate switches without being able to
confirm the status when in the power conservation mode, when the
printer returns to the operating mode in response to input from the
2
switch operations, the printer may perform operations that were not
intended by the user, or more specifically operations that are not
required. Because the user must restore the printer to the state
before the operation was performed when this happens, the user is
compelled to perform extra work.
SUMMARY
[0006]
A printer and a control method for a printer according to the
present invention can prevent unnecessary operations being performed
as a result of switch operations performed when the operating state
is set to the power conservation mode.
[0007]
A printer control method according to a first aspect of the
invention includes steps of: displaying power conservation mode
information indicating the operating state is set to a power
conservation mode on a display unit and monitoring input from
operation of a switch after the operating state changes from an
operating mode in which processes including a printing operation are
executed to the power conservation mode in which power consumption
is less than in the operating mode; returning the operating state from
the power conservation mode to the operating mode based on input from
operation of the switch; changing the display unit from displaying
the power conservation mode information to displaying status
information while holding the operating state in the power
conservation mode when input from operation of the switch is detected
while the power conservation mode information is displayed on the
display unit; changing the operating state from the power
conservation mode to the operating mode when input from operation of
the switch is detected while the status information is displayed on
the display unit; and after the operating state changes from the power
conservation mode to the operating mode, executing a process based
3
on the input detected while the status information is displayed on
the display unit.
[0008]
When input from operation of a switch is detected while the power
conservation mode information is displayed on the display unit in the
power conservation mode in this aspect of the invention, the process
based on the detected input is not executed. The printer can therefore
be prevented from executing unintended processes that are not
required as a result of operating switches without being able to
confirm the status information. However, when input from operation
of a switch is detected in the power conservation mode, status
information is displayed on the display unit while the operating state
remains set to the power conservation mode. The printer can therefore
suppress increased power consumption while enabling the user to
confirm the status information. In addition, if input from operation
of a switch is detected while status information is displayed on the
display unit, the operating state returns to the operating mode, the
process called by the switch input is executed, and the operation
intended by the user can be executed without delay.
[0009]
A printer control method according to another aspect of the
invention also has steps of: counting the elapsed time from when the
display unit changes from displaying the power conservation mode
information to displaying status information; resetting the display
unit from displaying the status information to displaying the power
conservation mode information if new input from operation of the
switch is not detected before the elapsed time exceeds a preset time;
and changing the display unit from displaying the power conservation
mode information to displaying the status information while holding
the operating state in the power conservation mode if input from
operation of the switch is detected while the power conservation mode
information is displayed on the display unit.
4
l
This aspect of the invention can reset the display unit to
displaying the power conservation mode information when the user
checks the status information displayed in the display unit based on
input from operating a switch once, and then determines that operating
a switch again is not necessary.
[0010]
Another aspect of the invention is a printer that changes the
operating state between an operating mode in which processes
including a printing operation can be executed, and a power
conservation mode with lower power consumption than the operating
mode, the printer including: a display unit; a switch; a monitoring
unit that monitors input from operation of the switch when in the power
conservation mode; a display control unit that displays power
conservation mode information indicating that the operating state is
set to the power conservation mode on the display unit when the
operating state changes from the operating mode to the power
conservation mode, and replaces the power conservation mode
information with status information on the display unit when input
from operation of the switch is detected while in the power
conservation mode; an operating state control unit that holds the
operating state in the power conservation mode when input from
operation of the switch is detected while the power conservation mode
information is displayed on the display unit in the power conservation
mode, and changes the operating state from the power conservation mode
to the operating mode when input from operation of the switch is
detected while the status information is displayed on the display unit
in the power conservation mode; and a processor unit that does not
execute the process based the detected input when input from operation
of the switch is detected while the power conservation mode
information is displayed on the display unit in the power conservation
mode, and executes the process based on the input after changing the
operating state from the power conservation mode to the operating mode
5
'
when input from operation of the switch is detected while the status
information is displayed on the display unit in the power conservation
mode.
[0011]
When input from operation of a switch is detected while the power
conservation mode information is displayed on the display unit in the
power conservation mode in this aspect of the invention, the processor
unit does not execute the process based on the detected input. The
processor unit can therefore be prevented from executing unintended
processes that are not required as a result of operating switches
without being able to confirm the status information. However, when
input from operation of a switch is detected in the power conservation
mode, the operating state control unit holds the operating state set
to the power conservation mode and the display control unit displays
status information on the display unit. The printer can therefore
suppress increased power consumption while enabling the user to
confirm the status information. In addition, if input from operation
of a switch is detected while status information is displayed on the
display unit, the operating state control unit returns the operating
state to the operating mode, and the processor unit executes the
process called by the switch input. The operation intended by the user
can therefore be executed without delay.
[0012]
A printer according to another aspect of the invention
preferably also has a timer that counts the time elapsed from when
the display unit starts displaying the status information when the
display unit changes from displaying the power conservation mode
information to displaying status information in the power
conservation mode. The display control unit resets the display unit
from displaying the status information to displaying the power
conservation mode information if input from operation of the switch
is not detected before the elapsed time exceeds a preset time.
6
This aspect of the invention can reset the display unit to
displaying the power conservation mode information when the user
checks the status information displayed in the display unit based on
input from operating a switch once, and then determines that operating
a switch again is not necessary.
[0013]
Further preferably in another aspect of the invention, the
display control unit displays the power conservation mode information
in a first display format on the display unit, and displays the status
information in a second display format that is different from the
first display format; and power consumption when displaying in the
first display format is less than or equal to power consumption when
displaying in the second display format.
This aspect of the invention can further reduce power
consumption in the power conservation mode.
[ 0 014]
Further preferably, to suppress power consumption by the display
in the first display format, the display unit has one or a plurality
of LEDs, and the first display format has all LEDs turned off or one
LED turned on.
Effect of the Invention
[0015]
When input from operation of a switch is detected while the power
conservation mode information is displayed on the display unit in the
power conservation mode in this aspect of the invention, the process
based on the detected input is not executed. The printer can therefore
be prevented from executing unintended processes that are not
required. However, when input from operation of a switch is detected
in the power conservation mode, status information is displayed on
the display unit while the operating state remains set to the power
conservation mode. The printer can therefore suppress increased power
consumption while enabling the user to confirm the status information.
7
In addition, if input from operation of a switch is detected while
status information is displayed on the display unit, the operating
state returns to the operating mode, the process called by the switch
input is executed, and the operation intended by the user can be
executed without delay.
Other objects and attainments together with a fuller
understanding of the invention will become apparent and appreciated
by referring to the following description and claims taken in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an external oblique view of a printer according to the
invention.
FIG. 2 is a section view showing the configuration of main parts
of the printer.
FIG. 3 is a basic block diagram showing the control system of
the printer.
FIG. 4 is a plan view of the operating panel.
FIG. 5 is a flow chart of the switching operation that switches
between the power conservation mode and the operating mode.
FIG. 6 describes switching between the power conservation mode
and the operating mode.
DESCRIPTION OF EMBODIMENTS
[0017]
A preferred embodiment of a printer according to the present
invention is described below with reference to the accompanying
figures.
[0018]
General configuration
FIG. 1 is an external oblique view of a printer according to this
embodiment of the invention. FIG. 2 is a basic section view showing
8
the configuration of the main parts of the printer.
As shown in FIG. 1, the printer 1 according to this embodiment
of the invention has a basically rectangular printer case 2, and a
paper guide 3 that projects up and toward the back of the printer from
approximately the middle between the front and back (also referred
to as the longitudinal direction herein) of the printer case 2. An
opening 4 is disposed in the front panel of the printer case 2, and
this opening 4 is covered by a cover 5 that is attached to open and
close to the front of the printer case 2. A power switch 6 is disposed
beside the cover 5. An operating panel 7 is disposed above the cover
5. the operating panel 7 includes a display unit 8 and four switches
9a to 9d. The display unit 8 includes five LEDs Sa to 8e.
[0019]
A paper exit 10 is disposed in the top of the printer 1 extending
in the transverse direction at a position in front of and near the
paper guide 3. An operating lever 11 is disposed beside the paper guide
3, and the operating lever 11 projects up from the top of the printer
case 2. An operating knob 12 is disposed at the side of the printer
case 2. As shown in FIG. 2, part of the printer case 2 behind the paper
guide 3 is omitted, forming a recess 13. A tractor unit 14 is disposed
in this recess 13.
[0020]
A platen roller 15 that determines the printing position A, and
a printhead 17, are disposed inside the printer case 2. The platen
roller 15 is disposed with its axis of rotation aligned with the
transverse direction, and is driven by drive power from a paper feed
motor 16. The operating knob 12 is connected to the platen roller 15.
When power is not supplied to the paper feed motor 16, the platen
roller 15 can be turned using the operating knob 12.
[0021]
The printhead 17 is mounted on a carriage 18 and disposed
opposite the platen roller 15. The printhead 17 is a serial impact
9
dot matrix printhead that prints by striking an ink ribbon with a
recording wire and transferring ink from the ink ribbon to the print
medium. The carriage 18 is mounted on a carriage guide 19 that extends
transversely, and is moved transversely along the carriage guide 19
by a carriage moving mechanism 20.
[0022]
A first conveyance path 21 from the paper guide 3 past the
printing position A to the paper exit 10, a second conveyance path
22 from the opening 4 past the printing position A to the paper exit
10, and a third conveyance path 23 from the tractor unit 14, through
an opening 13a in the recess 13, past the printing position A, and
to the paper exit 10, are formed inside the printer case 2. When
cut-sheet paper is used as the print medium, the print medium is
conveyed through the first conveyance path 21 or second conveyance
path 22. When continuous paper is used as the print medium, the print
medium is conveyed through the third conveyance path 23. The first
to third conveyance paths 21 to 23 are selected by operating the
operating lever 11.
[0023]
A cutter 24 that extends transversely along the edge of the paper
exit 10 is fastened adjacent to the paper exit 10. A media sensor 25
that detects if print media is loaded is disposed where the first
conveyance path 21, second conveyance path 22, and third conveyance
path 23 merge. A cover open sensor 26 for detecting if the cover 5
is open or closed is disposed near the opening 4 in the front of the
printer case 2.
[0024]
When the printer 1 power is turned on by operating the power
switch 6, the printer 1 starts in the operating mode in which the
printing operation can be performed. When the operating lever 11 is
operated and print medium is set in the first conveyance path 21,
second conveyance path 22, or third conveyance path 23 and detected
10
by the media sensor 25, the printer 1 enters a standby mode waiting
for print data to be supplied from an external device.
[0025]
If a switch 9a to 9d or the operating lever 11 is not operated
before a predetermined reference time passes after the standby mode
is entered, or print data is not supplied within this reference time,
the printer 1 changes the operating state from this normal operating
mode to a power conservation mode that consumes less power than the
normal operating mode.
[0026]
However, if input from operating a switch 9a to 9d or input from
operating the operating lever 11 is received before this reference
time passes, the printer 1 executes the operation called by this input.
If print data is supplied to the printer 1 before the reference time
passes, and a start printing command is contained in the print data,
the printer 1 drives the paper feed motor 16, or the paper feed motor
16 and the tractor unit 14, and conveys the print medium through the
first conveyance path 21, second conveyance path 22, or third
conveyance path 23. The printer 1 also drives the printhead 17 while
moving the carriage 18 carrying the printhead 17 in the transverse
direction (the direction along the carriage guide 19) perpendicular
to the print medium conveyance direction by means of the carriage
moving mechanism 20, and prints on the print medium passing the
printing position A.
[0027]
When printing ends, the printer 1 enters the standby mode waiting
for print data to be supplied from an external device. If print data
is not supplied within this reference time, or input from operating
a switch 9a to 9d or input from operating the operating lever 11 is
not received within the reference time after the standby mode is
entered, the printer 1 changes the operating state from this normal
operating mode to the power conservation mode.
11
[0028]
Control system
FIG. 3 is a block diagram showing the control system of the
printer 1. The controller 29 of the printer 1 includes a CPU 33, print
control unit 3 0, operating status monitor 31, operating state control
unit 32, input monitor 36, display control unit 37, and print buffer
35.
[0029]
Connected to the controller 29 are a communication unit 34
including a communication interface, the media sensor 25, the cover
open sensor 26, the switches 9a to 9d, the operating lever 11, the
display unit 8 (LEDs Sa to Be), the tractor unit 14, the paper feed
motor 16, the printhead 17, and the carriage moving mechanism 20.
[0030]
The CPU 33 centrally controls parts of the printer 1, and
functions as a processor that controls printer operation by running
a specific program and processing data.
The print control unit 30 (processor unit) controls the printing
operation of the printer 1, and controls driving the paper feed motor
16 and tractor unit 14 to convey the print medium through the first
conveyance path 21, second conveyance path 22, or third conveyance
path 23. The print control unit 30 conveys the controls the printhead
17 and carriage moving mechanism 20 while conveying the print medium
to print on the print medium passing the printing position A.
[0031]
The input monitor 36 (monitoring unit) monitors input from
operating the switches 9a to 9d regardless of the operating state.
The display control unit 37 displays status information
(information indicating the printer state) or power conservation mode
information indicating that the operating state is set to the power
conservation mode on the display unit 8.
[0032]
12
When in the operating mode and input is received from operation
of the switches 9a to 9d, the print control unit 30 executes the
process (operation) based on input from the switches 9a to 9d.
When the operating state changes from the power conservation
mode to the operating mode, and when status information is displayed
on the display unit 8 in the power conservation mode, the print control
unit 30 executes the operation called by input from operation of the
detected switch 9a to 9d.
When input from operating the operating lever 11 is received,
the print control unit 30 executes the process called by input from
operating the operating lever 11 while holding the same operating
state.
When print data is supplied from an external device, the print
control unit 30 writes the print data to the print buffer 35 while
holding the same operating state, and if a start printing command is
contained in the print data, executes the printing operation based
on the print data after the operating state enters the operating mode.
[0033]
When the operating state is set to the operating mode, the
display control unit 37 displays status information on the display
unit 8. When the operating state changes from the operating mode to
the power conservation mode, the display control unit 37 displays
power conservation mode information on the display unit 8. When input
from operation of a switch 9a to 9d is detected in the power
conservation mode, the display control unit 37 changes the display
unit 8 from displaying the power conservation mode information to
display status information.
The display control unit 37 also has a timer 38. When in the power
conservation mode and the information displayed on the display unit
8 changes from the power conservation mode information to the status
information, the display control unit 37 counts the time elapsed since
the status information was displayed. If new input from operation of
13
a switch 9a to 9d is not detected before this elapsed time exceeds
a previously set time T (see FIG. 5), the display control unit 37
returns the content displayed on the display unit 8 from the status
information to the power conservation mode information.
[0034]
The operating status monitor 31 monitors operation of the print
control unit 30 in the operating mode, and sends a switching command
to change the operating state from the operating mode to the power
conservation mode to the operating state control unit 32 when the
print control unit 30 does not perform any operation for a
predetermined reference time. More specifically, the operating
status monitor 31 has a timer 39, counts the time elapsed in the
standby mode after the printer 1 enters the standby mode, and sends
the switching command to the operating state control unit 32 when this
elapsed time exceeds the reference time.
[0035]
The operating state control unit 32 changes the operating state
between the operating mode and the power conservation mode.
The operating mode is the state in which power is supplied to
the print control unit 30 and power is supplied to the paper feed motor
16. In the operating mode, the print control unit 30 can execute
processes based on input from operation of a switch 9a to 9d, and can
execute the printing operation that drives the paper feed motor 16
and printhead 17 based on print data.
The power conservation mode is the state in which power is not
supplied to the paper feed motor 16. The power conservation mode
includes a state in which power is supplied to the CPU 33, and a state
in which power supply to the CPU 33 is stopped. The operating mode
must be resumed from the power conservation mode in order to execute
operations that drive the paper feed motor 16 and printhead 17.
[0036]
The operating state control unit 32 changes the operating state
14
from the operating mode to the power conservation mode when in the
operating mode and the switching command is received from the
operating status monitor 31. The operating state control unit 32
shares the input monitor 36 with the print control unit 30, and
monitors what the display control unit 3 7 displays on the display unit
B. When in the power conservation mode and input from operation of
a switch 9a to 9d is detected while the power conservation mode
information is displayed on the display unit 8, the operating state
control unit 32 holds the operating state in the power conservation
mode. When in the power conservation mode and input from operation
of a switch 9a to 9d is detected while status information is displayed
on the display unit 8, the operating state control unit 32 changes
the operating state from the power conservation mode to the operating
mode.
[0037]
When in the power conservation mode, print data is supplied from
an external device, and a start printing command is detected in the
print data, the operating state control unit 32 changes the operating
state from the power conservation mode to the operating mode. The
start printing command may be a line feed command instructing a line
feed operation, for example.
[0038]
Operating panel
The operating panel 7 including the display unit 8 and switches
9a to 9d is described next with reference to FIG. 4. FIG. 4 is a plan
view of the operating panel 7.
The operating panel 7 has five LEDs Sa to Be as the display unit
B. The display control unit 37 displays the printer 1 status and
printer 1 operating state by driving selected LEDs Sa to Be in the
on, blinking, or off states, for example. Status information
displayed on the display unit 8 includes, for example, font status
information, tear-off status information, whether or not print medium
15
is loaded, and whether operation is paused.
[0039]
The font status information identifies which of the plural fonts
installed in the printer 1 is the font that is set for use when printing.
The font status information is displayed by the first LED Sa and second
LED Sb. The set font is expressed by turning either one of the first
LED Sa and second LED Sb on, causing either one of the first LED Sa
and second LED Sb to blink, or causing both the first LED Sa and second
LED Sb to light steady.
When continuous paper having a perforation formed at a constant
length interval is used as the print medium, the tear-off status
information indicates if the perforation has been moved to the cutting
position by a function that automatically positions the perforation
in the continuous paper to the cutting position of the cutter 24 after
printing is completed. The tear-off status information is indicated
by the on or off state of the third LED Sc.
The status information indicating if print medium is loaded
indicates if the print medium is set, or more specifically if the media
sensor 25 detected the print medium. This print medium status
information is indicated by the on or off state of the fourth LED Sd.
The status information indicating if operation is paused more
specifically indicates if the printing operation of the printer 1 is
paused. This pause status information is indicated by the on or off
state of the fifth LED Se.
[ 0 04 0]
When the printer 1 is in the operating mode, the user looking
at the operating panel 7 can know that the printer 1 is in the operating
mode because at least one of the first LED Sa and second LED Sb
displaying the font information will be on or blinking. More
specifically, the font status information displayed by the display
control unit 37 on the display unit S also indicates if the operating
state of the printer 1 is the operating mode.
16
When the printer 1 enters the power conservation mode, the
display control unit 37 displays the power conservation mode
information indicating that the operating state is set to the power
conservation mode on the display unit 8. The power conservation mode
information is expressed by turning on only the fifth LED Be. The
display state (first display format) in which the fifth LED Be is on
and the first LED Sa to fourth LED Bd are off differs from the display
state (second display format) used to display status information, and
the user looking at the operating panel 7 can know that the printer
1 is in the power conservation mode.
[ 0 041]
Because the power conservation mode information is displayed by
turning one LED on, less power is consumed to display the power
conservation mode information than to display the status information.
More specifically, turning on one LED reduces the amount of power
required to operate the display and reduces the amount of power
required for LED control compared with causing the LED to blink
because blinking control is not required. Power consumption in the
power conservation mode can therefore be suppressed.
[0042]
The first switch 9a on the operating panel 7 inputs a command
for selecting the font. The second switch 9b inputs a command for
advancing the print medium toward the paper exit 10. The third switch
9c inputs a command for reversing the print medium away from the paper
exit 10. The fourth switch 9d inputs a command to pause printing. Note
that with the operating panel 7 used in this embodiment,
simultaneously pressing a plurality of switches 9a to 9d, or pressing
the fourth switch 9d for an extended time, inputs a change command
for changing the commands that are input by operating each of the
switches 9a to 9d, and the command input by operating each of the
switches 9a to 9d is changed by inputting this change command.
Commands other than those described above can therefore be input
17
depending upon the combination of first to fourth switches 9a to 9d
operated.
[0043]
Changing the operating state
The operation that switches the operating state between the
power conservation mode and operating mode is described next with
reference to FIG. 5 and FIG. 6. FIG. 5 is a flow chart of the switching
operation. FIG. 6 (a) is a timing chart of the paper feed motor 16,
display unit 8, and CPU 33 during the switching operation, and FIG.
6 (b) is a graph of power consumption at the timing points shown in
(a) .
The flow chart starts with the printer 1 having just completed
the printing operation, and the operating state is therefore set to
the operating mode (step ST1). As shown in FIG. 6, power is supplied
to the paper feed motor 16 and CPU 33 in step ST1.
[0044]
In the operating mode, the operating status monitor 31 also
monitors operation of the print control unit 30, and when the print
control unit 30 is detected to be in the standby mode and the time
past in the standby mode exceeds the reference time (step ST2, step
ST3), the operating status monitor 31 sends a switching command to
the operating state control unit 32, and the operating state control
unit 32 changes the operating state of the printer 1 from the operating
mode to the power conservation mode (step ST4). When the operating
state of the printer 1 changes from the operating mode to the power
conservation mode, the display control unit 37 changes the content
of the display unit 8 from the status information to the power
conservation mode information (step ST5). As shown in FIG. 6,
energizing the paper feed motor 16 stops in step ST5. Energizing the
CPU 33 also stops. As described above, the time past in the standby
mode is counted by the timer 39.
[0045]
18
If input from operation of a switch 9a to 9d is detected while
the power conservation mode information is displayed on the display
unit 8 in the power conservation mode (step ST6 returns YES), the
operating state remains set to the power conservation mode but the
content displayed on the display unit 8 changes from the power
conservation mode information to the status information. More
specifically, the display control unit 37 changes the content of the
display unit 8 to the status information while the operating state
control unit 32 holds the operating state set to the power
conservation mode (step ST7). Input from operating a switch 9a to 9d
is handled as a trigger to change the content of the display unit 8
to the status information display, and operations based on that input
are not processed. Processing operations that are not required by the
printer 1 because the switches 9a to 9d are operated without being
able to confirm the status information can therefore be prevented.
In addition, because the operating state remains in the power
conservation mode and only the display of the display unit 8 changes
from the power conservation mode information to the status
information in step ST7, the printer 1 enables the user to confirm
the status information while suppressing increased power consumption.
More specifically, in step ST7 as shown in FIG. 6, power is supplied
to the CPU 33 without supplying power to the paper feed motor 16, and
the content displayed by the display unit 8 changes from the power
conservation mode information to the status information.
[ 0 04 6]
If new input from operation of a switch 9a to 9d is not detected
before the time past after the display unit 8 changes from the power
conservation mode information to the status information exceeds the
preset timeT (step ST8 returns NO), the display control unit 37 resets
the display unit 8 from displaying the status information to the power
conservation mode information (step ST5). As a result, the display
unit 8 can be reset to the power conservation mode information when
19
the user checks the status displayed on the display unit 8 in response
to operation of the switch 9a to 9d in step ST6 and then decides that
further operation of the switches 9a to 9d is not required. As shown
in FIG. 6, energizing the CPU 33 is stopped and the display unit 8
changes from displaying status information to displaying the power
conservation mode information in step ST5. As described above, the
elapsed time is counted by the timer 38.
[ 0 04 7]
If new input from operation of a switch 9a to 9d is detected
before the time past after the display unit 8 changes from the power
conservation mode information to the status information exceeds the
preset timeT (step ST8 returns Yes}, the operating state control unit
32 changes the operating state from the power conservation mode to
the operating mode (step ST9}. As shown in FIG. 6, power is supplied
to the CPU 33 and paper feed motor 16 in step ST9.
[ 0 04 8]
When the operating state changes from the power conservation
mode to the operating mode, the print control unit 30 processes the
operation based on input from the switch 9a to 9d operation detected
in step ST8 (step ST10}. Note that the switch 9a to 9d operated in
step ST8 could be the switch 9a to 9d operated in step ST6, or a switch
9a to 9d that was not operated in step ST6. In either case, the
operation called by the input from the switch 9a to 9d operated in
the preceding step ST8 is processed in step ST10.
[0049]
If after the power conservation mode (step ST4} is entered there
is no input from operation of a switch 9a to 9d (step ST6 returns NO}
but input from operation of the operating lever 11 is detected (step
ST11}, the print control unit 30 processes the operation based on
input from operation of the operating lever 11 while remaining in the
power conservation mode.
[0050]
20
If after the power conservation mode (step ST4) is entered there
is no input from operation of a switch 9a to 9d (step ST6 returns NO)
but print data is supplied from an external device, the print data
is written to the print buffer 35 (step ST12) while remaining in the
power conservation mode. If a start printing command is contained in
the print data written to the print buffer 35 (step ST13 returns YES),
the operating state control unit 32 changes the operating state from
the power conservation mode to the operating mode (step ST9). After
the operating state returns to the operating mode, the print control
unit 30 executes the printing operation to print on the print medium
based on the print data (step ST10) . If the operating state of the
printer 1 goes from the operating mode to the power conservation mode
in step ST4, print data is then supplied from an external device, and
a start printing command is not contained in the print data written
to the print buffer 35, the operating state control unit 32 holds the
operating state in the power conservation mode, and changes the
operating state from the power conservation mode to the operating mode
when a start printing command is next supplied form the external
device.
[0051]
When the process or printing operation is completed in step ST10,
control returns to step ST1 and step ST2, and the operating status
monitor 31 monitors operation of the print control unit 30.
[0052]
Other embodiments
The operating state control unit 32 does not change the operating
state from the power conservation mode to the operating mode when
input from operation of the operating lever 11 is detected in the
foregoing embodiment, but the operating mode could be enabled.
Configurations that change the operating state to the operating
mode when the media sensor 25 detects the print medium in the power
conservation mode, or when the cover open sensor 26 detects the cover
21
was opened in the power conservation mode, are also conceivable.
[0053]
The power conservation mode information is displayed by turning
one LED (fifth LED Be) on in the foregoing embodiment, but all LEDs
could be turned off to display the power conservation mode information.
This configuration further reduces power consumption in the power
conservation mode.
[0054]
Energizing the CPU is stopped in the power conservation mode in
the foregoing embodiment, but power consumption may alternatively be
suppressed by lowering the operating frequency of the CPU in the power
conservation mode from the frequency used in the operating mode. The
power conservation mode could also be a sleep mode that stops the clock
while energizing the CPU.
[0055]
The invention being thus described, it will be obvious that
it may be varied in many ways. Such variations are not to be regarded
as a departure from the spirit and scope of the invention, and all
such modifications as would be obvious to one skilled in the art are
intended to be included within the scope of the following claims.

We Claims
1. A printer control method comprising steps of:
displaying power conservation mode information indicating the
operating state is set to a power conservation mode on a display unit
and monitoring input from operation of a switch after the operating
state changes from an operating mode in which processes including a
printing operation are executed to the power conservation mode in
which power consumption is less than in the operating mode;
returning the operating state from the power conservation mode
to the operating mode based on input from operation of the switch;
changing the display unit from displaying the power conservation
mode information to displaying status information while holding the
operating state in the power conservation mode when input from
operation of the switch is detected while the power conservation mode
information is displayed on the display unit;
changing the operating state from the power conservation mode
to the operating mode when input from operation of the switch is
detected while the status information is displayed on the display
unit; and
after the operating state changes from the power conservation
mode to the operating mode, executing a process based on the input
detected while the status information is displayed on the display
unit.
2. The printer control method described in claim 1, further
comprising steps of:
counting the elapsed time from when the display unit changes from
displaying the power conservation mode information to displaying
status information;
resetting the display unit from displaying the status
information to displaying the power conservation mode information if
new input from operation of the switch is not detected before the
23
elapsed time exceeds a preset time; and
changing the display unit from displaying the power conservation
mode information to displaying the status information while holding
the operating state in the power conservation mode if input from
operation of the switch is detected while the power conservation mode
information is displayed on the display unit.
3 . A printer that changes the operating state between an operating
mode in which processes including a printing operation can be executed,
and a power conservation mode with lower power consumption than the
operating mode, the printer comprising:
a display unit;
a switch;
a monitoring unit that monitors input from operation of the
switch when in the power conservation mode;
a display control unit that displays power conservation mode
information indicating that the operating state is set to the power
conservation mode on the display unit when the operating state changes
from the operating mode to the power conservation mode, and
replaces the power conservation mode information with
status information on the display unit when input from operation of
the switch is detected while in the power conservation mode;
an operating state control unit that holds the operating state
in the power conservation mode when input from operation of the switch
is detected while the power conservation mode information is
displayed on the display unit in the power conservation mode, and
changes the operating state from the power conservation
mode to the operating mode when input from operation of the switch
is detected while the status information is displayed on the display
unit in the power conservation mode; and
a processor unit that does not execute the process based the
detected input when input from operation of the switch is detected
24
while the power conservation mode information is displayed on the
display unit in the power conservation mode, and
executes the process based on the input after changing the
operating state from the power conservation mode to the operating mode
when input from operation of the switch is detected while the status
information is displayed on the display unit in the power conservation
mode.
4. The printer described in claim 3, further comprising:
a timer that counts the time elapsed from when the display unit
starts displaying the status information when the display unit
changes from displaying the power conservation mode information to
displaying status information in the power conservation mode;
wherein the display control unit resets the display unit from
displaying the status information to displaying the power
conservation mode information if new input from operation of the
switch is not detected before the elapsed time exceeds a preset time.
5. The printer described in claim 3 or 4, wherein:
the display control unit displays the power conservation mode
information in a first display format on the display unit, and
displays the status information in a second display format that is
different from the first display format; and
power consumption when displaying in the first display format
is less than or equal to power consumption when displaying in the
second display format.
6. The printer described in claim 5, wherein:
the display unit has one or a plurality of LEDs,- and
the first display format has all LEDs turned off or one LED turned
on.