SU886046A1 - Device for retreiving data from memory units - Google Patents

Description

I

The invention relates to memory devices and can be used in devices for sampling data pulses and sync pulses (SI) when reading information from external storage devices (memories) of cyclic action, such as magnetic discs.

A device for retrieving information from memory blocks is known, which contains a trigger, one-shot, AND-NOT and NOT 1 elements.

However, this device can only be used in those channels, the cord is strictly certain that the first pulse arriving at the device input is a sync pulse. If this condition is not fulfilled and whether the first SI pulse or the data pulse is unknown, it is impossible to use such a device for sampling data pulses and the SI.

The closest to the proposed technical entity is a device for retrieving information from the memory BTS, which contains the SI and data separation node, a counter, a decoder, an output switch, two triggers, and the outputs of the triggers are coupled with the control inputs of the output switch, the device input is connected to the input of the SR and data separation node, the outputs of which are connected to the information inputs of the output switch, the outputs of the counter are connected to the corresponding inputs of the decoder, the output of which is connected to the output Settings in the first flip-flop, the output koch mutator outputs are connected to sootvetsgvuk tsimi device 2 outputs.

The disadvantages of this device are the large amount of equipment and the lack of control over the operation of the device.

The purpose of the invention is to simplify the device.

Claims (2)

This goal is achieved by the fact that a device for retrieving information from a memory block containing a signal distributor, a counter, a decoder, a output switch, the first and second flip-flop, whose outputs are connected with digits of the output switch, whose information inputs are connected to the outputs of the signal distributor , the outputs of the counter are connected to the corresponding inputs of the decoder, the output of which is connected to the installation input of 1 flip-flops, the inputs of the signal body and the outputs of the output switch are respectively, the inputs and one of the device outputs, the control switch and the third trigger, the outputs of which are connected to one of the inputs of the control switch and the groping inputs of the first and second triggers, respectively, are entered, the first output of the control switch is connected to the counting input of the counter, the second output - with the input of the third trigger and with the installation input into the counter, the other information inputs of the control switch are connected to the outputs of the signal distributor. With an atom in order to increase the reliability of the device, it is advisable to supplement it with an element AND whose inputs are connected to the outputs of the first and second triggers, and the output of the element AND is the extreme output of the device. FIG. 1 shows a functional diagram of the proposed device; in fig. 2 - time diagram of the operation of this device. The device contains a 1 signal distributor, spooled for separation of SI and data | the first 2 and second 3 triggers, the output switch 4, the counter 5, the decoder 6, the third trigger 7, is the counting trigger, the control switch 8, the AND 9 element, which has output 1O (Fig. 1). The outputs of the trigger 7 are connected to him from the inputs of the control switch 8 and to the gate inputs of the first 2 and second 3 triggers, respectively, the first output of the control switch 8 is connected to the counting input of the receiver 5, the second output is connected to the input of the third router 7 and to the installation input About the counter 5, the other inputs of the control switch 8 are connected to the outputs of the distributor 1 of the signals. A: The outputs of switch 4 are one of the outputs of the devices. The inputs of the AND 9 element are connected to the outputs of the first 2 and second 3 triggers, and the output of the ELISA A 9 is a different output of the device ... The distributor 1 produces a preliminary separation of the input pulse sequence of the SI and the sequence of data pulses, and the first read pulse, like the corresponding sequence, is always output to the definite output of the distributor I, regardless of whether the first pulse of the SR or the data pulse. FIG. 1 position 11-21 The points at which the pulse waveforms shown in FIG. 2. Before describing the operation of the device, we note that in the pulse sequence read from the magnetic disk track, there is a service-. On the information, representing the characteristic code combinations. For example, in the combination, called the address marker, there is no sync pulse, and the information in this area is represented by units (data pulses). The address marker is the only combination in which there may be no SI, B combinations, called a space, followed by dm zeros (no data pulses). In this case, the condition m: .p + (. The indicated combinations are repeated in each of the records located on the magnetic disk track. The device uses the sample data and SI pulses for the specified code combinations. The device works as follows. Let the first pulse read is a data pulse (Fig. 2, pos. 11), the Pass through the control switch 8, this pulse sets the counter S to O and flushes trigger 7 on the falling front (Fig. 2, pos. 12). trigger outputs 7 change the state of the control its switch 8 in such a way that another output of the distribution; plug 1 is connected to the trigger 7; Shtele 1. The second impulse arriving at the device input (CI) through the control switch 8 enters the installation input at the O counter 5 and repacks the trigger 7 at the falling edge etc. (Fig. 2 pos., iSrie). Thus, if both data and SI pulses are present in the sequence, each pulse sets Counter 0 to O and interrupts trigger 7. If there is no data pulse after SI ( information position is recorded logical O), then with epuyuschy SI via control 1 | 6schy switch 8 extends to the count input of the counter 5 and changes its state by one (Fig. 2, pos. 17). Similarly, if there is no SI after the data pulse, then the next data pulse goes to the counting input of counter 5 (Fig. 2, pos. 17). Thus, counter 5 counts the number of zeros going further, then in SI, then in data, depending on the state of the trigger 7. If at any time counter 5 counts off more than m HyjBft, this means that the sequence arriving at its counting input is identified as CI. The decoder. 6 is configured to consist- (- 1. Its output signal sets in .1 either the first 2 or. The second 3 triggers depending on the state of trigger 7 (Fig. 2, pos. 18). The signals from the output of the flip-flops 2 and 3 are different, the passage of the SI pulse sequences in the data through the output switch 4 to the corresponding outputs of the device decides. 2, pos.) If in the Cpc output network of SI and data in the input sequence due to carrier defects some Number of pulses are broken, then the separated SI sequences and data at the outputs of the distributor 1 are reversed and. will not match the outputs of the device. In this case, when reading the next space, both the flip-flops 2 and 3 will be installed in 1 and the error signal at the output 1O of the element 9 will show. In the proposed device, the hardware costs are reduced compared with the known. In addition, the presence of a functional Control allows to increase. the accuracy of the output data and reduce the unproductive load of the rest of the computing system devices (for example, an input / output channel, a working memory, etc.). Claims I. Device OLYA retrieve information from memory blocks containing a signal distributor, a counter, a decoder, an output switch, the first and second flip-flop, whose outputs are connected to the control inputs of the output switch and whose information inputs are connected to the outputs of the signal distributor, the outputs of the counter are connected to cooi by the corresponding inputs of the decoder, the output of which is connected to the installation input to the flip-flops, the inputs of the signal distributor and the outputs of the output switch are respectively to One of the devices and one of the devices, characterized in that, in order to simplify the device, it contains a control switch and a third trigger, the outputs of which are connected to one of the inputs of the control switch and the gate inputs of the first and second triggers, respectively. , the first output of the control switch is connected to the counter input of the counter, the second output is connected to the input of the third trigger and to the input of the installation at the O counter, the other inputs of the control switch are connected to the outputs of the signal distributor. 2. A device according to claim 1, characterized in that, in order to increase the reliability of the device, it comprises an AND element, the inputs of which are connected to the outputs of the first and second triggers, and the output of the AND element is another output of the device. Sources of information | taken into account during the examination 1. USSR author's certificate 514338, cl. Gi 11 S 7/00, 1974. 2. USSR author's certificate on. Vk № 2479588 / 18-24, for l. 5 11 С 7 / ОО, 1977 (prototype). 40  "About to . t :: S g;:; CNJ