JPH04312039A - Message-fluctuation preventing circuit of automobile tracking apparatus - Google Patents

Abstract

PURPOSE: To prevent oscillation of various messages by synchronizing various messages with a data clock in an automatic vehicle tracking device. CONSTITUTION: This circuit consists of a data clock generation part 10 which generates the data clock, a microcomputer 20 which receives the data clock of the data clock generation part 10 to output various messages generated in a vehicle, and a latch 30 which receives various messages from the microcomputer 20 and latches and outputs them synchronously with the data clock generated by the data clock generation part 10. Since various messages generated in the vehicle are synchronized with the data clock to prevent the oscillation of messages and error does not occur, the address of the vehicle and the classifications of messages are accurately recognized at the time of demodulation.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a message trembling prevention circuit for precisely synchronizing various messages in an automobile tracking device with a data clock to prevent message trembling.

0002

2. Description of the Related Art Generally, when a vehicle tracking device sends an emergency situation (panic) message or a stolen vehicle message to a master station, the master station demodulates this message to confirm the vehicle address and the type of message. . At this time, there is a problem in that the transmitted message is not synchronized with the data clock and an error occurs, making it impossible to confirm the vehicle address and message type during demodulation.

0003

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a data clock system for processing various messages generated by a vehicle tracking device such as an emergency situation, a stolen vehicle, etc. The purpose of the present invention is to provide a message anti-shake circuit that allows the vehicle address and message type to be accurately confirmed during demodulation.

Another object of the present invention is to provide a message tremor prevention circuit that can accurately synchronize various messages with a data clock to prevent errors from occurring.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a circuit diagram according to the present invention, which includes a data clock generating section 10 that generates the data clock, and a microcomputer 20 that receives the data clock from the data clock generating section 10 and outputs various messages for the vehicle. and a latch 30 that inputs various data from the microcomputer 20 and latches and outputs the data in synchronization with the data output of the data clock generator 10.

FIG. 2 is an operational waveform diagram of each part in FIG.
This will be explained in detail with reference to . Data clock generator 10
A data clock as shown in FIG. 2A is generated.

The microcomputer 20 to which the data clock generated by the data clock generator 10 is input is shown in (B) in FIG.
) outputs a message like this. The phenomenon in which the output message of the microcomputer 20 oscillates with respect to the data clock as shown in FIG. This occurs because it becomes impossible to do so.

Therefore, the latch 30, which inputs the message as shown in FIG. 2(B) output from the microcomputer 20, receives the data clock output from the data clock generator 10 as shown in FIG. 2(C). Synchronize and latch output. Here, since the output message of the latch 30 is synchronized with the edge of the part where the message of the microcomputer 20 does not tremble, the address of the vehicle and the type of message are accurately determined during demodulation, thereby preventing the occurrence of errors.

0010

Effects of the Invention As described above, when a message such as a fire or a stolen vehicle is generated in a vehicle tracking device, this message is synchronized with the data clock to prevent message oscillation. This has the advantage of being able to accurately determine the address and type of message.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram according to the invention.

FIG. 2 is an operation waveform diagram of each part in FIG. 1;

[Explanation of symbols]

10 Data clock generation section 20 Microcomputer 30 latch

Claims (1)

[Claims] 1. A message tremor prevention circuit for an automobile tracking device includes a data clock generation section (10) that generates a data clock, and the data clock generation section (10).
a microcomputer (20) that outputs various messages generated in the vehicle in response to the data clock of 0), and data generated by the data clock generator (10) in response to various messages from the microcomputer (20). A message tremor prevention circuit for an automobile tracking device, comprising a latch (30) that outputs a latch in synchronization with a clock.