JPS5911422A - Microprocessor - Google Patents

Abstract

PURPOSE:To transmit the time information with the best efficiency in accordance with a system, by selecting optionally plural unit time outputs of an exclusive timing counter with a soft program instruction and using these outputs to interruption signals. CONSTITUTION:An output signal, e.g. a 1/100sec signal 2 is transmitted from a CPU1 and then supplied to a 1/10sec signal producing circuit 3. Thus a 1/10sec signal is obtained and then supplied to a one sec signal producing circuit 4 to obtain a 10sec signal. The one sec signal is supplied to a 10sec signal producing circuit 5 to obtain a 10sec signal. The 10sec signal is applied to one min signal producing circuit to obtain a one min signal. Each time signal is supplied to a multiplex signal selecting circuit 7, and a timing signal is selected by the output of an FF8 as an interruption signal to be sent to a CPU1. The FF8 is optionally set by an instruction exclusive to a soft program and holds a data until an instruction is newly set. Therefore a timing signal is selected as an optional interruption signal by setting instructions from the 1/100sec signal through the one min signal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an interrupt time setting method for a microprocessor that has a dedicated time counter and uses at least the time output of the dedicated time counter as an interrupt signal to execute software program processing.

Conventionally, in microprocessors that have a dedicated counter and use the output of the dedicated counter as an interrupt signal to calculate time through software program processing, the frequency of the interrupt signal is set relatively high in order to send time information over a wide range. I needed to.

However, setting a high frequency leads to an increase in software program processing time due to an increase in interrupt signals.

For example, if the output frequency of a dedicated counter is 1 Hz, an interrupt will be input once per second to execute software program processing, but if the output frequency of a dedicated counter is 10 Hz, an interrupt will be input once every 1/100 seconds. This means that the time dedicated to software program processing becomes longer.
This leads to a reduction in the time dedicated to other functional software programs.

Furthermore, an increase in software program processing time leads to an increase in power consumption in a microprocessor that operates under the control of high-speed signals, making it difficult to handle, especially in the case of IJS type portable microprocessors, which often operate on batteries.

However, if the output frequency of the dedicated counter is 111z, it is impossible to send out time information for a time shorter than 1 second, for example 1/10 second, ], 7100 seconds. Therefore, if the output frequency of the dedicated counter is set to 10011Z, the above-mentioned problem will occur.

If the output frequency of the dedicated counter is set to 100 fiz, an extra soft program operation will be performed when the time information is sent in units of one minute or more.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned conventional drawbacks and to provide a microprocessor that can select the interrupt time in a manner that allows the most efficient transmission of time information in accordance with the system.

The present invention will be explained below based on the drawings.

The drawing is a block diagram showing the configuration of a microprocessor of the present invention having a dedicated time counter, and 1 is a CI).
U (central processing unit), ROM511. It is assumed that it has all the functions of AM, etc., and will be described as CIIJ for convenience of explanation. The CPU 1 outputs an I/100 second signal 2 as an output signal. The 17100 second signal 2 is 1/]
The signal is inputted to the o second signal producing circuit B to produce a 1/10 second signal, and the 1/1 DEG second signal is sent to the 1 second signal producing circuit 4 to produce a 1 second signal. The 1-second signal is input to a 100-second signal producing circuit 5 to produce a 100-second signal, and the 100-second signal is sent to a one-shot signal producing circuit 6 to produce a 1-minute signal.

Furthermore, the 17100 second signal, 1/1o second signal, 1 second signal,
The 100 second and 1 minute signals are input to the multiplex signal selection circuit 7, and the output data of the flip-flop 8 controls and selects the word-1 hour signal as an interrupt signal to be sent to the CPLI 1. The flip-flop 8 is arbitrarily set by a dedicated command of the software program and holds data until a new command is sent. Therefore, by setting the command up to the /100 second signal, the second signal, and the 1 minute signal, the open time signal can be arbitrarily selected as an interrupt signal. The time measurement signal can be applied to a reference time signal, a timer, a stop watch, etc., and can be used as a similar interrupt signal by providing each hour counter according to the purpose. The interrupt signal is input to the interrupt processing circuit within the CPU 1, the start address of the software program corresponding to the interrupt signal is set in the program counter, and CPU processing is executed. The processing of CPLll is performed by a program to measure time after the interrupt time signal. The result of the arithmetic processing is stored in the RAM in the CP as necessary, and if it is necessary to display it externally, the data is transferred to a display circuit.

The power consumption of a circuit increases as the operating frequency increases. In particular, microprocessors use a high frequency signal as a system clock during execution processing, so the difference in power consumption during methane pie operation and during processing is significant. Therefore, it is most efficient to limit program processing to the minimum necessary. For example, if the timekeeping interrupt signal is a 1 second signal or a 1 minute signal, the processing time will be 60 times longer per minute, and the power consumption will be 60 times greater.

As is clear from the above explanation, according to the present invention, a software program arbitrarily selects output signals of a plurality of unit times and uses them as interrupt signals, thereby selecting a signal of the minimum required time measurement unit as an interrupt signal. By doing C
The processing execution time of the PU can be effectively reduced, resulting in a significant reduction in power consumption.

[Brief explanation of the drawing]

The drawing is a block diagram showing the configuration of a microprocessor according to the present invention. 1, CI) U including ROM and RAM. 2...1/] 00 second signal, 6...1/1o second signal generation circuit, 4...1
Second signal generation circuit, 5...100 second signal generation circuit, 6...1-shot signal generation circuit, 7...Multiple signal selection circuit, 8...Flip・Flop. Patent applicant Citizen Watch Co., Ltd.

Claims (1)

[Claims] (1) In a microprocessor that has a dedicated time counter and executes software program processing using at least the time measurement output of the dedicated time counter as an interrupt signal, a plurality of unit time outputs of the dedicated time counter are used as a software program.
The interrupt signal is arbitrarily selected according to a program instruction, and a clip-flop is set, and the selection of the plurality of unit time outputs is controlled by the output signal of the flip-flop. A microprocessor according to claim 1.