JPH0362634A - Selective individual call receiver - Google Patents

Abstract

PURPOSE:To attain the notice of a power voltage drop as a change in a melody frequency, or a speed change or a simultaneous change of the frequency and speed by receiving a decode output and the output of a voltage detection section and controlling a melody generation section. CONSTITUTION:When the voltage of a power supply 212 of a voltage detection section 109 is lower than a preset voltage generated from a reference voltage generating circuit 211, the output SLVS of a comparator 213 goes to H. Since its own call number is not yet detected, an output SDEC from a decoder 103 goes to L, resulting that the output SPDC of an AND circuit 222 of a melody control section 105 goes to H. The H level of the output SPDC is fed to a programmable frequency divider 223 simultaneously. The frequency divider 223 frequency-divides the clock from a reference clock section 110 with a 1st predetermined frequency division ratio to generate an output SCLK when a control signal input is at an L level and frequency-divides the clock with a 2nd frequency division different from the 1st predetermined frequency division ratio to generate an output SCLK when the control signal input is at an H level.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an individual selective calling receiver that notifies a call by a melody, and in particular, a device for notifying a drop in power supply voltage by a change in the frequency and speed of the melody. This invention relates to an improved individual selective calling receiver.

[Conventional technology]

Conventional individual selective calling receivers notify the call with an intermittent tone of a single audio frequency or a combination of multiple audio frequencies, and a power supply voltage drop is notified by a continuous tone of a single audio frequency or a combination of multiple audio frequencies. It was reported. On the other hand, an individual selective call receiver having a melody-based call notification means has also been provided, but this also uses the continuous tone mentioned above to notify of a drop in the power supply voltage.

[Problem to be solved by the invention]

The above-mentioned conventional individual selective call receiver notifies the user of a drop in power supply voltage using a single audio frequency or a combination of multiple audio frequencies, which is extremely irritating to the wearer's hearing and is unpleasant for the user. The downside was that it wasn't comfortable.

For this reason, conventional individual selective calling receivers have been subject to limitations in terms of where and when they can be used.

SUMMARY OF THE INVENTION An object of the present invention is to provide an individual selective call receiver that eliminates the above-mentioned drawbacks.

[Means to solve the problem]

The present invention provides an individual selective calling system having a call notification means for notifying the caller with a melody when receiving the own call number, and a power supply voltage drop notification means for notifying the caller when the power supply voltage has decreased. In the receiver, the power supply voltage drop notification means includes a power supply voltage detection circuit and a control circuit that controls a driving frequency of a melody generating circuit in the call notification means based on the output of the power supply voltage detection circuit. It is characterized by being

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of one embodiment of the invention.

This individual selective calling receiver has an antenna 101. Receiving section (
RX)102. Decoder (DEC) 103. Call number storage ROM (ID ROM) 104.
Melody control section (CONT) 105. Melody generator (MEL, GEN) 106. Melody amplification section 107° speaker 108. Voltage detection section (
LVS)109. Reference clock section (CLK) 110
It is equipped with

FIG. 2 is a more specific circuit diagram.

The voltage detection section 109 includes a reference voltage generation circuit 211. Power source (generally uses batteries) 212. It is composed of a comparator 213 for detecting a drop in power supply voltage.

The melody control section 105 includes an inverter 221 and an AND circuit 222. Programmable frequency divider 223 OR circuit 224 . It is composed of a rising pulse generation circuit 225.

The melody generating section 1.06 includes an external clock input buffer 2311, an address decoder 232. Melody-information storage circuit (generally ROM is used) 2
33. Melody generator 178234. It is composed of a low-pass filter 235.

In the figure, 201 is a call notification reset switch.

Next, the operation of this embodiment will be explained.

First, the operation when a call notification is made during notification of a power supply voltage drop will be described with reference to the signal waveform diagram of each part in FIG.

When the voltage of the power supply 212 of the voltage detection unit 109 becomes lower than the preset voltage generated by the reference voltage generation circuit 211,
The output S_LVS of the comparator 213 becomes a high level (hereinafter expressed as "'H"). At this time, since the own calling number has not been detected yet, the output S DEC from the decoder 103 is at a low level (hereinafter expressed as "L"), and as a result, the AND circuit 22 of the melody control section 105
The output SPDC of 2 becomes "H".

At the same time, the “H” level of the output 5PDC is applied to the programmable frequency divider 223.

When the control signal input is "'L", the frequency divider 223 divides the clock from the reference clock section 101 by a predetermined first frequency division ratio to generate an output SCLK. When the signal input is "Hn", the frequency is divided by a second frequency division ratio different from a predetermined first frequency division ratio to generate an output SCLK.

In this case, the output S PDC of the AND circuit 222 is “H”
” Therefore, the frequency divider 223 divides the clock by the second frequency division ratio and passes the output SCLK to the external clock manual buffer 231 of the melody generation section 106.

On the other hand, the output S FDC of the AND circuit 222 is the OR circuit 2
24, and its output SMa is further applied to a rising pulse generation circuit 225.

The rising pulse generation circuit 225 generates a pulse ssy having a predetermined time width when the output SMT of the OR circuit 224 changes from “L” to “H” or when it changes from “H′′ to “L I+”. Output once.

In this case, since the outputs S and T have changed from "°L" to "'TOI", pulses S and A are output and applied to the melody generation circuit 234 of the melody generation section 106.

When the melody generating circuit 234 receives the pulse SST once, it starts the melody and generates the output SMEL, and then when it receives the pulses S and A again, it starts the melody.
is stopped to stop generation of the output SMEL, and this operation is repeated thereafter. Note that the operation of the melody generating section 106 is well known, so a description thereof will be omitted.

In this case, the melody generation circuit 234 generates a melody corresponding to the second frequency division ratio, and the speaker 108 notifies the voltage drop.

As described above, when a self-calling number is received while reporting a voltage drop, the output SDEC from the decoder 103 becomes 'H' at the time the self-calling number is received.

Therefore, the AND circuit 222 of the melody control section 105
The gate of S19. is closed and the output S19. becomes "L", and the programmable frequency divider 223 divides the reference clock by a first frequency division ratio to generate an output SCLK. At the same time, the OR circuit 224 continues the previous state H". Therefore, the outputs S and 4A of the OR circuit 224 do not change, and the rising pulse generation circuit 225 does not output pulses S and A, and the melody is generated. The unit 106 outputs the melody outputs S and 4L started by the power supply voltage notification without stopping.
Melody outputs S and L corresponding to the first frequency division ratio are emitted to notify the carrier of the call.

Next, the output S DEL of decoder 103 is
The timer inside the decoder 10 automatically changes to "'L" after a certain period of time, or the decoder 10 is artificially turned off by pressing the reset switch 201 for stopping the call notification.
Set the output Sntc of No. 3 to “H”. As a result, the output SPI,c of the AND circuit 222 becomes "H" again, and the frequency divider 223 performs frequency division at the second frequency division ratio. On the other hand, the OR circuit 224 continues to be at "H", the rising pulse generating circuit 225 does not output the pulse ssr, and as a result, the melody generating circuit 234 generates a melody corresponding to the second frequency division ratio. It generates an output SML to notify the wearer that the voltage is low.

Next, the operation when a drop in power supply voltage is detected during call notification will be described with reference to the signal waveform diagram of each part in FIG. 4.

When a low voltage is detected during a call notification, the gate of the AND circuit 222 is closed as described above, so the output S
Until llEC operates the internal timer of the decoder 103 or the call notification reset switch 201 and reaches °'L゛°, it generates melody outputs S and L corresponding to the first frequency division ratio, and outputs S. When DEC becomes "°L", a melody output SNL corresponding to the second frequency division ratio is generated to notify the carrier of the low voltage.

[Effects of the Invention] As explained above, the present invention has a control section that receives the decoder output and the output of the voltage detection section as inputs and controls the melody generation section, thereby controlling a drop in the power supply voltage to a change in the frequency of the melody. , or a change in speed, or a simultaneous change in frequency and speed.

As a result, compared to conventional individual selective calling receivers, the present invention can notify the wearer of a drop in power supply voltage using a means that is extremely comfortable for hearing. , which has the effect of providing wide flexibility in usage time.

In addition, there is no need for a sound generation circuit dedicated to notifying power supply voltage drop, and only the melody generator for call notification can notify power supply voltage drop and call notification, thereby reducing the circuit size.

[Brief explanation of drawings]

Fig. 1 shows a block diadam that shows the basic configuration of an embodiment of the present invention, Fig. 2 shows a block diadam that shows the embodiment of Fig. 1 in detail, and Fig. 3 shows a call notification during notification of a drop in power supply voltage. FIG. 4 is a diagram showing the signal waveforms of each part in the case where a drop in power supply voltage is detected during the call notification. 101...Antenna 102...Receiving section 103...Decoder 104...ROM 105 for storing calling number
... Melody control section 106 ... Melody generation section 107 ... Melody amplification section 108 ... Speaker 109 ... Voltage detection section 110 ...・Reference clock section

Claims (1)

[Claims] (1) An individual selective call receiver having a call notification means for notifying the caller with a melody when receiving its own call number, and a power supply voltage drop notification means for notifying the caller when the power supply voltage drops. The power supply voltage drop notification means is comprised of a power supply voltage detection circuit and a control circuit that controls the driving frequency of the melody generation circuit in the call notification means based on the output of the power supply voltage detection circuit. An individual selective call receiver featuring: