JPH05122470A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To perform motor control with high accuracy by using several kinds of acceleration information tables properly without applying burden on a host CPU and increasing memory capacity on a slave CPU side in facsimile equipment provided with a ROM/RAM built-in type slave CPU for motor control other than the host CPU. CONSTITUTION:This equipment is provided with such feature that the several kinds of acceleration information tables are provided in a ROM 103 on a host CPU 101 side, and also, an area in which one acceleration information table can be stored in a RAM incorporated in the slave CPU 104 is provided, and one table out of a table group in the ROM 103 is selected before an original is read, and it is transferred to a storage area in the slave CPU 104, and a motor 105 can be rotated by a trigger command issued from the host CPU 101 by the slave CPU 104 based on acceleration information stored in the built-in RAM.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to motor control in a facsimile machine.

[0002]

2. Description of the Related Art Conventionally, in a facsimile machine, a stepping motor has been used as a drive source for conveying a read document. Particularly in recent years, more accurate motor control technology is required to achieve high image quality.

Therefore, as a means for responding to such a demand, a slave CPU dedicated to motor control is provided, and the host C
A method of controlling the motor under the control of the PU is adopted. As the slave CPU, ROM, RA
A one-chip microcomputer including an M, I / O control unit, etc. is used.

FIG. 2 is a block diagram showing a configuration example of a one-chip microcomputer. This one-chip microcomputer interrupts every desired cycle by setting a CPU 201, a RAM 202 for storing control variables used in a program, a ROM 203 storing a control program, and a timer value, for example. I / O control unit 205 for controlling the motor 207 through the phase excitation IC 206 and the timer 204 used for
And a bus I / F control unit 209 that realizes a command interface with the host CPU via the external bus 211.
And a slave CPU internal bus 210.

A method of controlling the motor having such a configuration will be described below.

First, a trigger command from the host CPU is received via the bus I / F control unit 209.

This trigger command includes frequency information and step number information.

For example, when moving 4 steps at 400 pps, the timer 204 is set to a value of 2.5 msec and an interrupt program for switching the excitation phase is generated every 2.5 msec. If the excitation phase is switched four times within this interrupt, the motor will move four steps. Further, in the case of rotating the motor at a high speed, acceleration control is required to accelerate from the self-starting frequency of the motor to reach a desired frequency.

FIG. 3 is a schematic diagram for explaining an example of acceleration control up to 1600 pps.

When a trigger command of 400 pps-1 step is received at the timing A in the figure, the slave CPU
Switches the excitation phase at the timing a in the figure and moves the motor by one step. It should be noted that this one step corresponds to one line of Super Fine called in the facsimile machine [15.
4 lines / mm].

Next, at the timing B in the figure, 800 pps
When receiving the -2 step trigger command, the slave CPU switches the excitation phase at the timings of b1 and b2 in the figure to move the motor by two steps. When a trigger command of 1600 pps-4 steps, which is a target to be reached, is received at the timing D in the figure, d1, d2, d in the figure are received.
The excitation phase is switched at the timing of 3 and d4. After that, the motor is rotated at 1600 pps by this trigger command.

On the other hand, in order to further reduce the load on the host CPU, the above-mentioned acceleration information is applied to the RO in the slave CPU.
It is taken as a table in M, and the host CPU simply issues a trigger command without being aware of acceleration
The method is to accelerate independently on the U side.

FIG. 4 is a schematic diagram showing an example of the acceleration information table in the ROM 203 of the slave CPU.

The slave CPU has several types of this acceleration information table, and selects one of them according to a command from the host CPU.

The data in the table is managed by the pointer. When the trigger command is received, the motor is moved at the frequency and the number of steps pointed to by the pointer, and then the pointer is set to the next data. By moving the pointer in this way, acceleration control can be easily realized. An end code is provided at the end of the acceleration information table.When the next data is the end code, the position of the pointer is fixed and the subsequent trigger command uses the frequency data and step number data pointed to. Rotate the motor.

[0016]

However, in the above-mentioned conventional example, the capacity of the built-in ROM of the one-chip microcomputer which is the slave CPU is small, and it is difficult to have many kinds of acceleration information tables.

Further, the one-chip microcomputer must be designed in consideration of the program capacity and the capacity occupied by the acceleration information table at all times, which is extremely inconvenient in program development.

The present invention is a facsimile apparatus capable of performing highly accurate motor control by selectively using a plurality of types of acceleration information tables without imposing a burden on the host CPU and without increasing the memory capacity on the slave CPU side. The purpose is to provide.

[0019]

According to the present invention, in addition to a host CPU that controls the entire apparatus, the host CPU
In a facsimile machine having a ROM for controlling a motor and a slave CPU with a built-in RAM under the control of the above, a plurality of types of acceleration information tables are provided in the ROM on the host CPU side, and a RAM with a built-in slave CPU is provided.
An area for storing one acceleration information table is provided in the table, one of the tables in the ROM is selected and transferred to the storage area in the slave CPU before the document is read, and issued from the host CPU. The slave CPU rotates the motor based on the acceleration information stored in the built-in RAM in response to the trigger command.

[0020]

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

The host CPU 101 is a CPU that controls the entire apparatus. The RAM 102 is mainly used by the host C.
The RAM 103 is a memory for storing the program control variables of the PU 101, and the RAM 103 is a memory for storing the control program of the host CPU 101. The slave CPU 104 is a dedicated sub CPU that controls the stepping motor 105.

Further, the apparatus includes a host CPU 10
Bus 106 that connects 1 to each unit, CCD and image processing IC
And the like, a sensor 108 for detecting the presence or absence of a document, and an operation unit 109 provided with various input keys and a display device.

The above description mainly shows the configuration required for the control of the present invention. In addition to this, the configuration of a normal facsimile device such as a modem for communication, a printer for recording, etc. Although provided, they are omitted here because they are not directly related to the description of this embodiment.

FIG. 5 is a block diagram for explaining the data flow of the acceleration information table in this embodiment.

The host CPU 101 has a plurality of types of acceleration information tables (505, 50) existing in the ROM 103.
6, 507) is selected. The selection unit is a key on the operation unit 109.

For example, when the operator selects standard, fine, or super fine, which is a document feeding mode in the sub-scanning direction in a facsimile machine, the host CP
The U 101 transfers the acceleration information table to the slave CPU 104 via the bus 106. Slave CPU 104
Shows the received acceleration information table in area 5 of the internal RAM.
Set to 04. It should be noted that the data is transferred here under the agreement that the data should be transferred from the lower frequency side.

Specifically, as shown in FIG. 6, after first issuing a data transfer start command, frequency data 1, step number data 1, frequency data 2, step number data 2, ... Frequency data N, step The number data N is sequentially transferred. Then, by issuing a data transfer end command, the end code is set at the end of the acceleration information table storage area 504.

Here, the frequency data is slave C
If the PU 104 actually sets the value to the timer 204, the conversion work on the slave CPU 104 side becomes unnecessary.

After the setting of the acceleration information table is completed as described above, in response to a trigger command from the host CPU 101, first, the motor 1 is set to the head data of the table.
Move 05 to set the pointer to the next data.

Thereafter, the motor 10 is moved while moving the pointer.
5 is moved, and when the last data (arrival target data) in the table is reached, the motor 10 with the pointer fixed
Rotate 5.

When reading a manuscript of a plurality of pages,
The acceleration information table may be transferred before reading each page.

In this case, the operation unit 109 is operated by the sensor 108 at the timing when the trailing edge of the previous page has passed the reading position and the leading edge of the next page has arrived before the reading position.
The information on the next page is acquired from and the corresponding acceleration information table is transferred.

Furthermore, during direct transmission in which a document is transmitted while being read, the acceleration information table may be selected depending on the communication mode (standard, fine, super fine).

[0034]

According to the present invention, a high-precision motor control can be performed by properly using a plurality of types of acceleration information tables without burdening the host CPU and without increasing the memory capacity of the slave CPU side. Because you can
In particular, even when a one-chip microcomputer having a small ROM capacity is used as a slave CPU, it is possible to realize various patterns of motor feed control.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing a configuration example of a one-chip microcomputer.

FIG. 3 is a schematic diagram illustrating an example of motor acceleration control.

FIG. 4 is a schematic diagram showing an example of an acceleration information table stored in a ROM of a conventional slave CPU.

FIG. 5 is a block diagram illustrating a data flow of an acceleration information table in the above embodiment.

FIG. 6 is a schematic diagram showing a data transfer sequence in the above embodiment.

[Explanation of symbols]

 101 ... Host CPU, 102 ... RAM, 103 ... RAM, 104 ... Slave CPU, 105 ... Stepping motor, 106 ... Bus, 107 ... Scanner, 108 ... Sensor, 109 ... Operation part.

Claims (3)

[Claims] 1. A host CP that controls the entire apparatus.
In addition to U, a facsimile machine having a ROM for controlling a motor and a slave CPU with built-in RAM under the control of the host CPU, a plurality of types of acceleration information tables are provided in the ROM on the host CPU side, and slaves are provided. An area for storing one acceleration information table is provided in the RAM with a built-in CPU,
Acceleration information stored in the internal RAM by the slave CPU in response to a trigger command issued from the host CPU by selecting one of the tables in the ROM and transferring it to the storage area in the slave CPU before reading the original. A facsimile machine characterized by rotating a motor based on the. 2. The reading apparatus according to claim 1, further comprising an operation key for selecting an acceleration information table stored in the ROM on the host CPU side, and reading a document of a plurality of pages before reading each page. A facsimile apparatus, characterized in that, by obtaining key information, one is selected from the acceleration information table group based on the key information and transferred to the slave CPU. 3. The direct transmission according to claim 1, wherein one of the acceleration information table groups stored in the ROM on the host CPU side is selected and transferred to the slave CPU based on the communication mode. And a facsimile machine.