JP2002259086A - Printer controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer controller for saving proper power consumption. SOLUTION: Documents and images, etc., prepared on a host device 2 such as a PC, are prepared by converting them into a page description language (PDL, hereafter) with a printer driver 21. The prepared PDL documents and images are sent out via a communication route, such as a network to a printer 1. In a printer controller 11, the number of the commands of a CPU is predicted from the received PDL documents and images. Regarding the prediction of conversion from PDL commands to the number of CPU instructions, the correspondence data table of the number of the CPU instructions is provided from the PDL command, based on an experience value, and referencing and addition are performed. Thus, the number of the CPU instructions in a band unit or a page unit can be predicted easily. The predicted number of the CPU instructions and the performance value (for instance, the number of CPU instructions processible in one second) of the CPU are compared.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a printer controller, for example, a printer controller applied to a printer function unit of an MFP (copy / printer / fax).

[0002]

2. Description of the Related Art Conventionally, printer controllers are generally
It is configured as a control unit of a printer using a CPU.

[0003] The C mounted on the printer controller
The operating frequency of a PU is generally constant when the power is on. Exceptionally, methods such as lowering the frequency or stopping operation in the energy saving mode and the like have been adopted.

[0004]

However, in the above-described conventional system, the normal operation is always performed at a constant operating frequency. For this reason, even when drawing a page that does not place a load on the CPU (for example, a text document), a current necessary for the CPU flows and the current is consumed uselessly.

In recent years, most of the power consumption of electronic devices mounted on a controller
U has a problem that the tendency is more remarkable for CPUs with higher processing capacity.

The present invention has been made in view of the above problems, and has as its object to provide a printer controller that provides good power consumption.

[0007]

According to a first aspect of the present invention, there is provided a printer controller for predicting the number of CPU instructions executed by a printer controller from a drawing command generated by a printer driver. Features.

The printer controller according to the second aspect of the present invention is characterized in that, for example, the number of CPU instructions that can be processed in one second is stored as a data table as the processing performance value of the CPU.

The invention described in claim 3 is the first or second invention.
In the printer controller described in, the predicted CP
U instruction execution count and CPU installed
And dynamically switching to an optimum CPU operating frequency with reference to the processing performance value table.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a printer controller according to the present invention will be described in detail with reference to the accompanying drawings. Referring to FIGS. 1 and 2, one embodiment of the printer controller of the present invention is shown.

FIG. 1 is a block diagram showing an example of the overall system configuration. FIG. 2 is a diagram showing an example of a situation of frequency fluctuation.

In FIG. 1, a printer controller 11 according to the present embodiment is provided in a printer 1. The printer 1 includes a host device 2 such as a PC,
ork or the like via a communication path. The host device 2 has a printer driver 21.

(Explanation of Operation) An operation mode will be described.
Documents, images, and the like created on a host device (or machine) 2 such as a PC are converted and created by a printer driver 21 into a page description language (PDL).

The created PDL is sent to the printer 1 via a communication path such as a network. The printer controller 11 estimates the number of CPU commands from the received PDL.

With respect to the prediction of the conversion from the PDL command to the number of CPU instructions, P
It has a data table corresponding to the number of CPU instructions from the DL command, and refers to and adds the data table. This makes it possible to easily predict the number of CPU instructions in band units or page units.

The predicted number of CPU instructions is compared with the processing performance value of the CPU (for example, the number of CPU instructions that can be processed in one second).

The following is a table of processing performance values of the CPU for each frequency. Table 1 shows a relationship between the frequency, the processing performance value (instruction / second) of the CPU for each frequency, and the power consumption value.

[0018]

[Table 1]

The frequency correspondence table is shown below. This Table 2
Represents the relationship between the band or page No., the predicted CPU instruction value, the CPU frequency, the power consumption value, and the amount of power reduction as compared with the case where the device is constantly operated at 400 MHz.

[0020]

[Table 2]

As shown in Tables 1 and 2 above, the operating frequency of the CPU is selected from the compared data, and the frequency is dynamically changed.

The printing operation is completed by repeating the above operation in band units or page units.

From the above table, the following relationship is obtained. 1) Power consumption in the present invention: 10.1 W 2) Conventional power consumption: 18.0 W (40 on a regular basis)
3) Power reduction: 7.9 W

[0024]

As is clear from the above description, according to the printer controller of the first aspect of the present invention, a drawing command (PDL) generated by a printer driver is
By estimating the number of executed CPU instructions in the printer controller, for example, control in page units (band units) becomes possible.

In the printer controller according to the second aspect of the present invention, since the capability value of its own CPU is stored as a data table on the printer controller, the printer driver does not need to be conscious of the printer at all. Therefore, it is not necessary to take measures according to the model.

According to the printer controller of the third aspect of the present invention, by dynamically switching to the optimum CPU operating frequency by referring to the predicted number of instructions to be executed by the CPU and the ability value table of the mounted CPU. Thus, control can be performed in page units (band units), and as a result, current consumption can be made as necessary.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram to which a printer controller of the present invention is applied.

FIG. 2 is a diagram illustrating an example of a situation of frequency fluctuation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer 2 Host device 11 Printer controller 21 Printer driver

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Claims (3)

[Claims] 1. A printer controller for predicting the number of CPU instructions to be executed by a printer controller from a drawing command generated by a printer driver. 2. The processing performance value of the CPU is, for example, 1
A printer controller storing the number of CPU instructions that can be processed per second as a data table. 3. The dynamic switching to an optimal CPU operating frequency by referring to the predicted number of instructions executed by the CPU and a processing performance value table of the mounted CPU. A printer controller according to claim 1.