JPH11272571A - Automatic adjusting method of baud rate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic adjusting method of baud rate between a pendant and a controller capable of suiting mutual baud rate without providing the pendant with a switch for selecting the baud rate. SOLUTION: In a setting method of the baud rate between a terminal and the controller at a state that the terminal as a slave machine is connected with the controller as a master machine with a transmission line, a signal in which the baud rate by which either one of the terminal 2 or the controller 1 is capable of performing communication is included as data is transmitted for the other party by either one of the terminal 2 or the controller 1 and one's own baud rate is set based on the baud rate of the other party included in the signal by the other party which receives the signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a baud rate setting method, and more particularly to a method for automatically adjusting a baud rate between a terminal device such as a pendant and a controller body.

[0002]

2. Description of the Related Art Conventionally, automatic setting of a baud rate between a pendant (child device) and a controller (main unit, master device) has been performed by measuring a pulse period suitable for the baud rate as follows. Assuming that the pendant and the controller are connected by a transmission path (communication cable), the pendant first transmits a pulse signal of a predetermined number of bits in a predetermined cycle matching the baud rate to the controller. Controller (computer system included in the controller)
Can easily measure (count) the frequency or cycle of the pulse signal by a known technique, and set its own baud rate in accordance with the frequency, that is, the baud rate at which communication with the pendant is possible.

Now, it is assumed that the pendant is designed to have two types of baud rates. Conventionally, which baud rate is selected from these two types is manually selected. For example, a switch for baud rate selection is installed on the pendant,
By operating the switch, the baud rate is determined. Therefore, as described above, a pulse at the selected baud rate is transmitted to the controller, and the baud rate on the controller side is set according to the pendant.

In many cases, a plurality of pendants are connected to a controller. In the conventional baud rate setting method,
The switch must be operated or confirmed by the number of pendants. As described above, in the conventional baud rate setting method, when there are many pendants or the pendants are provided in various places, it is troublesome to operate the switch for setting the baud rate.

[0005]

SUMMARY OF THE INVENTION The present invention provides a method for automatically adjusting the baud rate between a pendant and a controller, wherein the baud rates can be adapted to each other without providing a switch for selecting the baud rate on the pendant. The purpose is to:

[0006]

The invention according to claim 1 is the following method. In a method of setting a baud rate between a terminal device and a controller in a state in which a terminal device serving as a child device and a controller serving as a parent device are connected via a transmission line, one of the terminal device and the controller sends its own A signal containing a communicable baud rate as data is transmitted, and the other receiving the signal sets its own baud rate based on the other party's baud rate contained in the signal. This is an automatic adjustment method.

[0007] The invention of claim 2 is the following method. In the setting method of the baud rate between the terminal device and the controller in a state where the terminal device as the child device and the controller as the parent device are connected by a transmission line, both the terminal device and the controller can communicate with each other. Transmit a signal that contains the appropriate baud rate as data,
A method of automatically adjusting the baud rate, in which the two receiving the signal set their own baud rate based on the baud rate of the other party included in the signal.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the first aspect of the present invention will be described. Either the pendant or the controller transmits a signal (referred to as A) containing the baud rate at which the pendant and the controller can communicate with each other as data. Here, description will be made assuming that the controller transmits the signal A. now,
The baud rate that the pendant can handle is 76 kbps and 1
Assume that it is 28 kbps. 76 pendant baud rate
When setting to kbps, the controller uses the signal A as, for example, 8C in hexadecimal (0100 in binary).
Data of 1100, decimal number 76) may be sent. Naturally, the baud rate for the pendant of the controller itself is set as 76 kbps. The pendant receives the signal A and decodes and recognizes 8C in hexadecimal, so the baud rate of the pendant is 76 kbp.
Set with s.

Conversely, consider the case where signal B is sent from the pendant to the controller. The signal B includes data (128 bps) indicating the baud rate of the pendant. If the controller approves it, the baud rate of both will be 128 kbps. If the controller doesn't like the baud rate 128kbps,
To that effect, it is sufficient to inform the pendant. The pendant is
Other baud rates (76 kb in this case)
ps) to the controller. That is, even when the signal B including the baud rate data is sent from the pendant to the controller, the baud rate of the pendant can be specified from the controller. Alternatively, a baud rate adjusting method according to the method of claim 2 described below may be adopted.

The invention according to claim 2 is the following method. Both the pendant and the controller
It transmits a signal containing the baud rate at which it can communicate as data. In other words, both companies transmit data including the baud rate. If the baud rates match, the baud rates will be the communication baud rates of the two companies. If they do not match, one of the baud rates will be adopted, and both will set their own baud rates. If the controller is designed so that the baud rate transmitted from the controller to the pendant is prioritized, the controller can select and determine the baud rate of the pendant without providing a switch or the like for selecting the baud rate in the pendant. However, if there is no baud rate in the pendant that matches the baud rate transmitted from the controller, the controller may adopt the baud rate transmitted by the pendant.

[0011]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram for explaining the first aspect of the present invention. With the communication cable (3a, 3b), the controller 1
It is assumed that TxD, which is the data transmission side of the pendant 2, and RxD, which is the data reception side, are mutually connected.
First, a baud rate (including data) is transmitted from the controller 1 to the pendant 2. It is assumed that the controller 1 knows in advance the baud rate that the pendant 2 can support. That is, such a configuration can be provided. The pendant 2 receiving (the data of) the baud rate from the controller 1 selects and sets the baud rate, and notifies the controller 1 that the baud rate has been acknowledged and set.

As described above, the baud rate of the pendant 2 can be specified within a range that the pendant 2 can support from the controller 1. Of course, the pendant 2 does not require a switch for setting the baud rate.

FIG. 2 is a block diagram for explaining the second aspect of the present invention. The baud rate is transmitted between the controller 1 and the pendant 2. The upper diagram in FIG. 2 shows the common operation when the baud rates match and when they match, and the lower diagram in FIG. 2 shows the upper diagram in FIG. 2 when the baud rates do not match. The next operation of the state is shown.

The controller 1 and the pendant mutually transmit the baud rate. In other words, it is the baud rate that you have set, and the baud rate that you want the other party to set. If the baud rates match, there is no need to adjust the baud rate, and the settings for both baud rates are determined at this stage. Of course, setting approval signals may be exchanged, but whether or not to do so is a matter of design choice for those skilled in the art.

Here, the description will be made assuming that the baud rate sent by the pendant has priority. The pendant 2 matches the baud rate received from the controller 1 with its own baud rate. If the received baud rate does not match its own baud rate, the controller 1 waits for the next signal to be transmitted from the controller 1. On the other hand, the controller 1 sets itself with the baud rate received from the pendant 2 and transmits a signal indicating that the setting is completed or a signal of the baud rate. Thus, the baud rate of the pendant 2 can be set to the baud rate of the controller 1.

Alternatively, in the second embodiment of the present invention, a method may be adopted in which transmission is continued while adjusting the baud rate until the two baud rates match.

[0017]

Since the present invention is configured as described above, the following effects can be obtained. By transmitting data including its own baud rate from one of the pendants or the controller or mutually, the other party can be notified of their own baud rate. Therefore, it is possible to provide a method of automatically adjusting the baud rate between the pendant and the controller, which can adjust the baud rates of the pendants without providing a switch for selecting the baud rate.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining the invention of claim 1;

FIG. 2 is a block diagram for explaining the invention of claim 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Controller 2 Pendant (terminal device) 3a, 3b Communication cable (transmission line)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04L 29/10 H04L 13/00 309C

Claims (2)

[Claims] In a method of setting a baud rate between a terminal device and a controller in a state where a terminal device serving as a child device and a controller serving as a parent device are connected by a transmission line, one of the terminal device and the controller is a partner. In response to this, a signal containing its own communicable baud rate is transmitted as data, and the other that receives the signal sets its own baud rate based on the baud rate of the other party included in the signal. Characteristic automatic baud rate adjustment method. 2. A method for setting a baud rate between a terminal device and a controller in a state in which a terminal device as a child device and a controller as a master device are connected by a transmission line, wherein both the terminal device and the controller communicate with each other. Transmitting a signal including the baud rate at which it can communicate as data, and receiving the signal, both of them set their own baud rate based on the baud rate of the other party included in the signal. How to automatically adjust the baud rate.