JP3158665B2 - Printer and control method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method of controlling the printer and its having a mechanical contact used in calculators and the like.

[0002]

2. Description of the Related Art Conventionally, in this type of technology, after a timing pulse which rises immediately after turning on a motor power is generated a predetermined number of times, initialization is performed using a timing pulse and a reset pulse, and printing / paper feeding is started. It was a control method.

FIG. 4 is a timing chart showing an operation method of a conventional general printer. Since the printer described in the present invention is described in JP-B-3-20352, only the control method will be briefly described.

First, a motor drive signal 51 is supplied to start the motor. After a predetermined number N of timing pulses 52 have been generated, a search for the rise of the reset pulse 53 is started, and the timing pulse 52 immediately after the rise of the reset pulse 53 is started. Is counted as TP0, and a character selection signal 54 is input at the position of the timing pulse 52 corresponding to the desired type and printing is performed. The interval between the rise and fall of the first digit character selection signal 54 is determined by the character selection signal 54.
The timer output signal 55 is started at the rising edge of the measurement, and the measurement is performed. Thereafter, the character selection is repeated by the required number of digits, and then several times the rising interval of the character selection signal 54 measured at the first digit in the uppermost digit is added after the input of the character selection signal 54. It is carried out.
The carriage return operation 56 ends with the carriage return energization C, and then the paper feed operation 57 ends. Thereafter, after printing and paper feeding are repeated for the required number of lines, the motor drive signal 51 is cut off to stop the motor.

A conventional printer control method will be described below with reference to a flowchart of FIG. 5 and a time chart of FIG. First, in step F61, the motor drive signal 70 is input to start the motor. In step F62, it is determined whether the timing pulse 71 has risen. If the timing pulse 71 has not risen here, step F
The control of 62 is repeated. When the timing pulse 71 rises, in step F63, the timing pulse 71
It is checked whether or not N has occurred a predetermined number of times or more. If the number is equal to or greater than the predetermined number N, the process proceeds to the control of detecting the rising edge of the reset pulse 72 in step F64. If the number of occurrences of the timing pulse 71 is less than the predetermined number of occurrences N, the control of steps F62 and F63 is repeated until the number of occurrences of the timing pulse 71 becomes equal to or more than the predetermined number of occurrences N. If the rise of the reset pulse 72 is detected in step F64, the rise of the timing pulse 71 is detected in step F65. The timing pulse 71 rising in step F65 is set to TP0 and
At 66, the count of the timing pulse 71 is set to TP0.

According to this printer control method, the rising edge of the reset pulse 72 detected immediately after the number of occurrences of the timing pulse 71 becomes equal to or more than the predetermined number of occurrences N is determined as the first rising edge of the reset pulse 72. In a printer having mechanical contacts, chattering 73 as shown in the drawing is generated in the waveform of the reset pulse 72 due to contact failure due to vibration and wear of the sliding portion of the contact. At the rising edge of the original reset pulse 72,
Since the number of occurrences of the timing pulse 71 is less than the predetermined number N, the first rise of the reset pulse 72 cannot be detected, and the number of occurrences of the timing pulse 71 is less than the predetermined number N.
3 is determined as the rising portion of the reset pulse 72, and the next rising of the timing pulse 71 is determined as T
Since miscounting is performed as P0, one printing position is delayed from a predetermined position, resulting in erroneous printing.

As described above, the timing pulse 71
The rising edge of the reset pulse 72 detected immediately after the number of occurrences of the reset pulse 72 becomes equal to or more than the predetermined number of occurrences N is determined as the first rising edge of the reset pulse 72, and the next rising edge of the timing pulse 71 is counted as TP0 and initialized. Setting was done.

[0008]

However, the above-mentioned prior art has the following disadvantages. (1) If chattering occurs in the waveform of the reset pulse due to contact failure due to vibration and wear of the sliding portion of the contact, a counting error occurs and a printer malfunction occurs. (2) In order to prevent the above-described malfunction, it is necessary to take measures to increase the cost by adding an integrating circuit with a capacitor or a resistor, or using expensive countermeasures such as gold-plated contacts. Was.

The present invention has been made to solve such a drawback, and the first rising edge of the reset pulse can be detected without using an expensive chattering countermeasure component and without being affected by chattering. The aim is to provide a reliable, highly reliable printer.

[0010]

According to the present invention, there is provided a printer comprising: means for rotating a character wheel by driving a motor; means for generating a first pulse in response to rotation of the character wheel;
Means for generating a second pulse once per rotation of the character wheel, wherein the printer performs initial setting of the character wheel by detecting an edge of the second pulse by the first pulse. Counting means for counting the first pulse; and judging means for judging whether or not the counting of the first pulse by the counting means is equal to or more than a predetermined number of occurrences. When it is determined that the count is equal to or greater than the predetermined number of occurrences, it is determined whether the edge of the second pulse has already been detected by the first pulse. When the edge of the second pulse has been detected, the second pulse has been detected. Is invalidated, and an initial setting value is obtained by a first pulse that detects an edge of a second pulse that arrives next, and the determination unit determines that the count of the first pulse is equal to the predetermined value. When it is determined that the number of times of birth is equal to or more than the number of times of birth, it is determined whether or not the edge of the second pulse has already been detected by the first pulse. An initial set value is obtained by a first pulse for detecting an edge. Further, the control method of the printer of the present invention includes:
Means for rotating a character wheel by driving a motor, means for generating a first pulse corresponding to the rotation of the character wheel, and means for generating a second pulse once for each rotation of the character wheel. The edge of the second pulse is connected to the first pulse.
A first determining step of counting the first pulse and determining whether the number of occurrences is equal to or greater than a predetermined number of times, in the printer control method of performing initial setting of the character ring by detecting with a pulse; A second determining step of determining whether or not the edge of the second pulse has already been detected by the first pulse when it is determined in the determining step that the count of the first pulse is equal to or greater than the predetermined number of occurrences. When the second determination step determines that the edge of the second pulse has been detected, the initial value of the second pulse is invalidated, and the edge of the second pulse that arrives next is detected. When the initial setting value is obtained by the first pulse, and it is determined in the second determination step that the edge of the second pulse has not been detected, the edge of the next incoming second pulse Characterized in that to obtain the initial set value by the first pulse to be detected.

[0011]

According to the above configuration of the present invention, even if chattering due to vibration and wear of the mechanical contacts occurs in the reset pulse that rises after the motor power is turned on to perform the initial setting, Can be reliably detected, and the timing pulse T
There is no hindrance to the count of P0, and malfunction of the printer can be prevented. Also, no expensive chattering countermeasure parts are used.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a flowchart illustrating a control method for performing initialization. FIG. 2 is a timing chart thereof, and FIG. 3 is a block diagram thereof.

As shown in the flowchart of FIG. 1, when starting the motor, first, a motor drive signal 20 for starting the motor is input in step F1, and the rising of the timing pulse 21 is confirmed in step F2. Here, the control of step F2 is repeated until the timing pulse 21 rises. When the timing pulse 21 rises, it is checked in step F3 whether the timing pulse 21 has occurred a predetermined number N or more. If the number is equal to or greater than the predetermined number N, the reset pulse flag 23 is determined in step F4. If the number of times of generation of the timing pulse 21 is less than the predetermined number of times N, the determination of the reset pulse flag 23 in step F5 is performed.

The reset pulse flag 23 is set to "1" by interruption processing when the rise of the reset pulse 22 can be detected during the period from the rise of the previous timing pulse 21 to the rise. 0 ". If it is determined in step F5 that the reset pulse flag 23 is "1", the process proceeds to step F6, where the reset pulse flag 23 is set to "0". Then, the process returns to step F2 to check the rise of the timing pulse 21. When it is determined in step F5 that the reset pulse flag 23 is "0", the process returns to step F2 to check the rise of the timing pulse 21.

In step F4, the reset pulse flag 23
Is "1", it means that the reset pulse 22 has been generated before step F4, and the timing pulse 2
Reset pulse 22 for counting TP0 of 1
Since the first rising edge cannot be detected, step F6
To set the reset pulse flag 23 to “0”,
Returning to step F2, the rising of the timing pulse 21 is confirmed. Reset pulse flag 2 in step F4
3 is "0", the timing pulse 2 immediately before
Since it was confirmed that the reset pulse 22 was not generated between the rise of 1 and the rise, the process proceeds to step F7 to detect the rise of the reset pulse 22. From this step F7, when the rise of the reset pulse 22 has been detected by the interrupt processing, the process proceeds to the next step F8. The rising of the timing pulse 21 is detected in step F8, and if detected, the rising timing pulse 21 is set in the timing pulse count TP0 in step F9. With this printer control method,
FIG. 2 is a timing chart when the initial setting is performed.

As shown in the timing chart of FIG.
The motor drive signal 20 for starting the motor is supplied, and the rise of the timing pulse 21 is confirmed. When the timing pulse 21 rises, it is confirmed whether the timing pulse 21 is equal to or more than a predetermined number N of occurrences. Here, since the number of occurrences is less than the predetermined number N, the rising of the next timing pulse 21 is waited again. The detection of the timing pulse 21 is continued until the number of occurrences reaches a predetermined number N or more, during which time the count of the timing pulse 21 remains TP0. The detection of the rising edge of the reset pulse 22 continues even during the period less than the predetermined number of occurrences N. The timing pulse 21 is detected a predetermined number of times N
If this is the case, the detection of the rise of the reset pulse 22 is continued, and the timing pulse 21 that first rises after the rise of the reset pulse 22 is counted as TP0, and the initial setting ends.

Printing and paper feeding are performed using the timing pulse 21 confirmed as described above. In FIG. 2, when the number of generations of the timing pulse 21 is N-1, the reset pulse 22
Rises, the reset pulse flag 23 is set to “1” by the chattering 24 of the reset pulse 22 generated when the number N of times of the timing pulse 21 is generated, but the reset pulse flag 23 is not “0”. In order not to proceed to the detection of the rising edge of the reset pulse 22 generated immediately before the TPO of the timing pulse 21, the reset pulse flag 23 is set to "0" again, and the process returns to the detection of the rising edges of the timing pulse 21 and the reset pulse 22.

The number of occurrences N + of the next timing pulse 21
Also at the time of 1, the reset pulse flag 23 is "1" due to the chattering 24 of the reset pulse 22 which has risen immediately before, so that the reset pulse flag 23 is reset to "1" again.
The timing pulse 21 and the reset pulse 22 are set to “0” and the process returns to the detection of the rise of the timing pulse 21 and the reset pulse 22. The next timing pulse 2
When the number of occurrences of 1 is N + 2, the reset pulse 22
Does not occur, the reset pulse flag 23 is set to "
0 ", and the process proceeds to the detection of the rising edge of the reset pulse 22, which occurs immediately before the TPO of the timing pulse 21, and the reset pulse 22 is generated immediately before the number of times N + X of the timing pulse 21 is generated. Is counted as TP0, and the state where the initialization is completed is illustrated.

As described above, since the reset pulse 22 rises at the number N-1 of times of generation of the timing pulse 21, the chattering 24 of the reset pulse 22 generated at the number N of times of generation of the timing pulse 21 causes the reset pulse 21 to rise. TP0 + 1 of the original timing pulse 21 by mistakenly determining that it is the first rising edge of TP0 can be prevented from occurring.

Next, an example of the control method of the present invention will be described with reference to the block diagram of FIG. The control unit includes a timer 40 for measuring time and a RAM for temporarily storing data being processed.
41, a ROM 42 for storing a program, a CPU 43 for controlling the whole program, an electromagnet drive circuit 44 for paper feeding and printing, a motor drive circuit 45 for driving a motor, a detection circuit 46 for detecting timing pulses,
And a detection circuit 47 for detecting a reset pulse. A portion 48 surrounded by a broken line on the right side indicates the printer main body side.

[0021]

As described above, according to the present invention, even if chattering due to vibration and wear of the mechanical contact occurs in the reset pulse that rises after the motor power is turned on for initial setting, the reset pulse Can be reliably detected, the counting of timing pulses is not affected at all, and malfunction of the printer can be prevented. In addition, a high-quality printer capable of preventing malfunction of the printer without using expensive chattering countermeasure parts can be provided.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an embodiment of the present invention.

FIG. 2 is a timing chart showing one embodiment of the present invention.

FIG. 3 is a block diagram showing an example of a control method according to the present invention.

FIG. 4 is a timing chart showing an example of the related art.

FIG. 5 is a flowchart showing an example of the related art.

FIG. 6 is a timing chart showing an example of the related art.

[Explanation of symbols]

F1 Motor drive signal input processing F2 Processing to determine the rise of timing pulse F3 Processing to determine whether a predetermined number of timing pulses have been generated F4 Processing to determine whether a reset pulse has risen F5 Processing to determine whether a reset pulse has risen F6 Reset pulse Processing to set the flag to "0" F7 Processing to determine whether the reset pulse has risen F8 Processing to determine the rise of the timing pulse F9 Processing to count the timing pulse to TP0

Claims (2)

(57) [Claims] Means for rotating a character wheel by driving a motor; means for generating a first pulse in response to rotation of the character wheel; generating a second pulse once for each rotation of the character wheel. Means for performing initial setting of the character ring by detecting an edge of the second pulse by the first pulse, wherein: a counting means for counting the first pulse; and And determining means for determining whether or not the count of the first pulse is equal to or greater than a predetermined number of occurrences. When the determination means determines that the count of the first pulse is equal to or greater than the predetermined number of occurrences, It is determined whether or not the edge of the second pulse has already been detected by the first pulse. If the edge of the second pulse has been detected, the second pulse
Invalidate the initial setting value by the pulse, and
An initial setting value is obtained by a first pulse for detecting an edge of a pulse, and when the determination unit determines that the count of the first pulse is equal to or more than the predetermined number of times, the edge of the second pulse is already determined by the second pulse. A printer characterized in that it is determined whether or not detection has been performed by one pulse, and when an edge of the second pulse has not been detected, an initial setting value is obtained by a first pulse that detects an edge of a next incoming second pulse. 2. A means for rotating a character wheel by driving a motor, means for generating a first pulse in response to rotation of the character wheel, and generating a second pulse once for each rotation of the character wheel. Means for performing initial setting of the character ring by detecting an edge of the second pulse by the first pulse, wherein the first pulse is counted and a predetermined number of occurrences is performed. A first judging step of judging whether or not the above is satisfied, and when it is judged by the first judging step that the count of the first pulse is equal to or more than the predetermined number of occurrences, the edge of the second pulse has already been detected. A second determining step of determining whether or not the edge of the second pulse has been detected by the second determining step. The initial setting value is invalidated, and the initial setting value is obtained by the first pulse for detecting the edge of the next incoming second pulse. The second determining step determines that the edge of the second pulse has not been detected. A first pulse for detecting an edge of a second pulse that arrives next to obtain an initial set value.