JPS594902B2 - encoding circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an encoding circuit in a transmission device for monitoring information at a distance.

A conventional circuit of this type is shown in FIG.

In the figure, 1a, Ib...In are input information,
2a, 2b...2n is an information input circuit, 3 is a scanning circuit for time-divisionally transmitting n pieces of information, and 4 is a parallel/serial circuit that converts n pieces of information into serial signals according to the scanning order. Converter circuit 5 indicates the serial code transmitted to the monitoring station. Further, 6 is a scanning signal, 7 is a signal selected by this scanning signal 6, and 8
is a control signal for the scanning circuit 3. Next, the operation will be explained.

The input information depends on its form, contact information for every 10 to 10 points, and measurement information for each amount of 1a, lb...In
(to) be divided into n pieces. This is received by information input circuits 2a, 2b, . . . 2n suitable for the format, and each information is converted into a signal of the same format. The scanning circuit 3 advances each time the parallel-to-serial conversion circuit 4 transmits one piece of information, and the scanning circuit 3 advances to the information input circuit 2a.
, 2b, . When scanning is completed up to n, the output of the scanning circuit 3 returns to 1 and scanning is repeated. Parallel-to-serial conversion circuit 4
Now, the scanning number signal from the scanning circuit 3 and the information input circuit 2a
, 2b...2n are converted into a combined serial pulse code 5 and sent to the monitoring station. Since the conventional encoding circuit is configured as described above, when the transmission time of one set of information is T, one period requires a transmission time of nXT.

In the case of the transmission speed of 200 BPS, which is currently commonly used, T is approximately 200 mS, and for example, when n = 25, 5 seconds are required for one period of transmission. There were drawbacks such as problems with the speed at which the station could follow the indicator. This invention was made in order to eliminate the drawbacks of the conventional ones as mentioned above.
The purpose of this invention is to make it possible to change the turning point of the scanning circuit depending on external conditions, thereby shortening the transmission period. An embodiment of the present invention will be described below with reference to FIG.

In Figure 2, 1a, 1b...1n12a, 2
b...2n, 4 to 8 indicate the same components as in FIG. Further, 9 is a scanning shortening signal that is input when it is necessary to shorten the transmission period, and 3b is a scanning circuit that always scans up to n, and when scanning shortening signal 9 is input, returns scanning at a preset point less than n. It is. Next, the operation shown in FIG. 2 will be explained.

Input information includes items that require a transmission cycle in the event of an emergency.
h, and place unnecessary items in the latter half 1-n. Normally, the scanning circuit 3b repeats scanning up to n as in FIG. 1, and all information is sequentially sent out by the parallel/serial conversion circuit 4. When it becomes necessary to shorten the information update due to the conditions of the monitoring station, the scanning circuit 3b receives the signal 9, advances the turning point from n to h, discards information 11-1n, and parallel-serial converter circuit 4 updates information 1a-1n. Only 1h is sent. Therefore, the transmission period is shortened to h/n. In addition, in the above example, the effect of improving the information update speed of measured values that perform set value control was described, but it is also possible to distribute necessary items to the first half for return contact information in the case of opening/closing operations, occurrence of important failures, etc. A similar effect of speeding up information transmission can be obtained by combining the shortened necessary condition generation circuit.

As described above, according to the present invention, by changing the turning point of the scanning circuit, the transmission cycle of necessary information items can be shortened, and the same effect as that of improving the transmission speed can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional encoding circuit, and FIG. 2 is a diagram showing an encoding circuit according to an embodiment of the present invention. In the figure, 1a, 1b...1n are input information,
2a, 2b...2n are information input circuits, 3, 3b
is a scanning circuit, 4 is a parallel-to-serial conversion circuit, 5 is a serial monitoring signal,
6 is a scanning signal, 7 is a scanned selection signal, 8 is a scanning circuit control signal, and 9 is a scanning shortening signal.

Claims (1)

[Claims] 1. An information input circuit that inputs multiple pieces of information, a scanning circuit that sequentially scans this information input circuit and repeats it, and a parallel-to-serial conversion circuit that converts it into multiple serial signals according to the scanning order of this scanning circuit. The scanning circuit normally repeats scanning up to n (n is an integer of 2 or more) information input circuits, and when the scan shortening signal is input, the scanning circuit repeats scanning up to a preset number of information input circuits less than n when the scan shortening signal is input. An encoding circuit characterized by repeating scanning up to the circuit.