SU725214A1 - Arrangement for discriminating the last pulse in pulse train - Google Patents

Description

(54) DEVICE FOR THE INTRODUCTION OF THE LAST IMPULSE IN A PUT

The invention relates to a pulse technique and can be used in information processing devices. A device for extracting a pulse, which solves the problem of isolating the last pulse from the input barium, containing three Kipp relays, a coincidence element, the prohibition element of the three driver and the trigger 1, is known. device is that it performs the selection of the last pulse under the condition of a constant period of pulse in the packet, since for solving the problem there is an expansion of the input pulses of 1/3 - 1/2 IRS their sequencer that may, at a constant period. This limits the scope of application of this device. It is also known that the device performs the selection of the last pulse in a packet, which includes two triggers, a coincidence element, two keys and a counter 2. In this device, the number of pulses in the packet is first determined, then the last pulse in the next burst is detected. e. It is possible that the last impulse is allocated only in every second pack and under the condition of a constant number of pulses in the packs. The aim of the invention is to improve the dynamic characteristics of the device, which provides the ability to isolate the last pulse in each pack, and to expand the functionality by ensuring operability with a random number of pulses in the packs. containing the first trigger, the output of which is connected to the input of the match element, the second trigger, the output of which is connected to the first control inputs of the two keys, and a counter, entered A series connected pulse distributor, a switch and a controlled divider, whose input is connected to the second control inputs of the keys, and the bit inputs of the controlled divider are connected to the counter outputs, the input of which is connected to the second input of the matching element. .

and the signal input of the first key, the output of which is connected to the input of the second trigger, wherein the output of the coincidence element is connected with the signal input of the second key, the input of the first trigger and the input distributes the pulses.

Fig, 1 shows the block diagram of the device; 2 shows timing diagrams for his work.

A device for extracting the last pulse in a burst contains a pulse distributor 1, a switch 2, a first key 3, a coincidence element 4, a first trigger 5, a second switch b, a second trigger 7, a controlled divider 8 and a counter 9.

The device works as follows.

When a pulse sequence arrives at the input of the device (fig. 2a), the trigger 5 each of its pulses is set to the state in which permission is given to the coincidence element 4 (fig. 2b), to which other input pulses arrive (fig. 26) The clock pulses following the input pulses pass an open match element and set the trigger to the home state. As a result, element 4 matches after each pulse the input sequence HQC and only one clock pulse r is removed. The input sequence pulses are temporarily assigned to TaKToafenvi pulses. Pulse sequence removed from element 4 (Fig. 2d) also goes to distributor 1 and to switch-off input of switch 6. Distributor 1 extracts the first pulse from the received sequence and outputs it to the first input of switch 2, removed from the second output of distributor 1 the remaining pulses of the sequence, which are output to the second input of the switch 2.

5 when the pulse arrives at the first input, the switch 2 drives the clock pulses to the counter 9, which counts their number (fig. 2e). When pulses arrive at the second input, the switch 2 outputs clock pulses to the controlled 8 (FIG. 2e). The code recorded in the counter 9 corresponds to the pulse repetition period in the input sequence and is used to set the division factor of the divider 8. In terms of output from the divider output. The sequence of pulses is removed, the period of which is equal to the period of the following impulses of the input

the sequence, while the beginning of the generated sequence is delayed relative to the beginning of the input sequence for two periods, and its end is delayed relative to the end of the input sequence - for one follow-up period of the input sequence (Fig. 2g). The pulses from the divider 8 turn on the keys 3, 6. When the key 3 is turned on, the latter issues on

Q is a counting trigger 7 clock pulses (Fig. 2z), which extracts every second of them (Fig. 2i) and outputs them to the pulse input of the key b and to the off input of the key 3. Until the moment of the last pulse arrives at the turn on input of the switch 5 6 from divider 8, the pulses to the signal input of the key b are received at the moments when the key b is closed. When entering the key b of the last .I1otulsa with divider 8,

0, the key is set to the open state, as a result, the next pulse from the flip-flops 7 passes to the output of the device (Fig. 2k).

Thus, the device issues

5 the last pulse from each packet of the input pulse sequence with a priori unknown following period and the number of pulses in them.

Claims (2)

1. USSR author's certificate 0 №414742, cl. H 03 K 21/36, 1972. 2. USSR author's certificate No. 531268, cl. H 03 K 5/153, 1975. mn Sign 8 Output . .. Fig 1