SU1430955A1 - Multichannel priority device - Google Patents

Description

(21) 4184597 / 24-24

(22) 01/19/87

(46) 10/15/88. Bul K 38 (72) A. Yu. Shcheglov and V. A. Bogatyrev f (53) 681.325 (088.8) (56) Khorovich P., Hill U. The Art of Circuit Engineering, M .: Mir, 1984, p. 543.

USSR Author's Certificate J 1198522, class, G 06 F 9/46, 1984.

Automation and Computer Engineering, 1986, No. 4, p. 48

(54) PRIORITY MULTI-CHANNEL DEVICE

(57) The invention relates to the field of computing technology and can be used in organizing calls of several subscribers to a common resource. The purpose of the invention is to increase the noise immunity of the device. Multi-channel priority device

contains To channels 1, pulse shaper 17, the element OR 18, the driver of the polling signals 9, each channel contains counters 2, delay elements 3 and 5, the element OR 4, trigger 6, element And 7, the driver of the pulses 8, the driver of the polling signals 9 , the resource capture request input 19, the resource capture confirmation output 20, the input 21 and the output 22 of each channel, the polling signal generator contains the elements OR 10 and 13, the one-shot 11, the pulse generator 12, the AND element 14, the delay element 16, the counter 15 , input 23 and output 24 of the coater als survey. In order for the channel 1 to be activated, it is necessary to form three polling pulses, which reduces the likelihood of the device to be triggered by the interference pulse. 4 il.

S

(L

About WITH

ate

SP

J

The invention relates to computing technology, in particular, to priority devices, and can be used to organize a common resource to be accessed by several subscribers, in particular, to a common highway.

The purpose of the invention is to improve the noise tolerance of the device.

FIG. 1 shows a functional diagram of the proposed device; in fig. 2 is a timing diagram, followed by the operation of the polling signal generator in FIG. 3 is a timing diagram explaining the operation of the device j in FIG. 4 is a trigger flow chart.

The device contains K channels 1, each of which contains a counter 2, a second delay element 3, an OR element 4, a first delay element 5, a trigger 6, an AND element 7, a pulse shaper 8, a polling signal generator 9, in each of the K channels 1 and before the first channel, the driver 9 of the polling signals contains .; the first element OR 10, the one-shot 11, the pulse shaper 12, the second element OR 13, the AND 14 element, the counter 15, the delay element 16, the pulse shaper 17, the OR element 18, in each of the K channels 1 there is a request control input 19, request confirmation control output 20, interrogation input 21, output device 22, interrogation signal generator input 23 and interrogation signal generator output 24, AND elements 25-28, outputs 30.30 AND elements 26,27, OR elements 31, 32 and outputs 33, 34. The device operates as follows.

In the initial state, trigger 6 and the counter 2 of all channels are in the zero state. When the device is turned on at the leading edge of the signal appearing at the input of the pulse former, the pulse appearing at its output triggers the transmitter 9 of the polling signals before the first channel, resulting in three polling pulses from its output through the element OR 18 to the input 21 of the first channel. These signals are counted by counter 2. If a high potential appears at the second output of counter 2, then on the leading edge of this signal (in the absence of a signal

five

0

five

0

five

0

five

0

five

la query i in the presence of a low potential at the control input 19 of the request, the trigger 6 of this channel is set to one and a high potential appears at the output of the element And 7, on the leading edge of which the kPulus generator starts the polling signal generator of the channel in question, as a result which produces a pulse that resets the counter 2 to the zero state and starts the polling signal generator 9, which outputs a polling signal to the output of this channel, consisting of a sequence of three pulses. If on all subsequent channels there are no .query signals, then the polling signal (in the form of three pulses) from the output of the last channel through the element OR 18 is fed to the input 21 of the first channel, etc. If the interrogation signal arrives at the input 21 of the channel ,, -la of the control input 19 of the request which has a high potential, when the rising edge of the signal at the output of the first delay element 5 appears, the trigger 6 of this channel is set to zero, a high potential appears the control output 20 confirming the request of the channel in question, and the low potential appearing at the first output of the trigger 6 does not pass the high potential through the element 7, as a result of which the polling of the other channels is stopped. When a high potential is removed from the jupe control; its input 19 of the request, trigger 6 is set to one, a low potential appears at the control output 20 of the request confirmation 20 as a result of which the polling of the channels resumes, starting with the next channel,

When a noise pulse appears at the input 21 of the channel5, which is not polled 5, one is signed to the counter 2, but the channel cannot be selected, since the second output of the counter 2 has a low potential. When a polling signal (three pulses) arrives at the input 21 of this channel, a high potential appears at the second output of counter 2, but since counter 2 in this case counts up to four, when adding a fourth unit

high potential appears at the third output of counter 2 and low at the second. To prevent the output of the OR 4 element from interfering with the fourth unit, a second delay element 3 is introduced, which in this case holds a high potential on the second output of the counter 2, while the high potential does not appear on the third output of the counter 2 (i.e. delay on the counter response time). When a pulse appears at the output of the trigger pulse generator

 the generator of polling signals of this signal, the counter 3 of this channel is set to the zero state and then it works as usual. On the other hand, when interference occurs due to the disappearance of one of the polling pulses, two pulses are received at the input 2t of the channel (instead of three). In this case, a high potential appears at the second output of counter 2, and the circuit operates normally.

Shaper signal survey operates as follows.

In the initial state, the counter 15 is in the zero state. When a pulse arrives at the input 23 of the interrogation signal generator, this impulse passes through the first element OR 10 and starts the one-shot 11. The pulse received at the output of the one-shot 11 passes to the output 24 of the interrogation signal generator (this is the first of the three pulses that make up the interrogation signal) and to the first counter input: 15, at the first output of which a high potential appears, on the leading edge of which arriving through the second element OR 13 at the input of the driver 12 pulses, the pulse received at its output through the first ment OR 10 OSCAL monostable multivibrator 11, the output pulse from monostable

 11 enters the output 24 of the formation. bodies of interrogation signals (this is the second pulse) and the first input of the counter 15. At the same time, the low potential appears on the first output of the counter 15 and the second output of the counter 15. will

; a certain time, at the second output of the counter 15 there is a high potential that will start the formation.}

A pulse pulse 12 and a one-shot 11, resulting in a third pulse at the output 24 of the interrogation signal generator. Simultaneously this

a pulse will come to the first input of the counter 15 and there will be a high potential at both its outputs (the state at the output of the second element OR 13 does not change (high potential), i.e. the pulse shaper does not start), as a result of which the counter 15 goes through Element AND 14 is reset to the zero state. The delay element 16 is introduced in order to obtain the leading edge of the signal at the output of the second element P1LI 13, when the second unit is added, to start the driver 12 pulses.

Claims (1)

Invention Formula 0 five 0 five A multichannel priority device containing K channels (K is the number of device request inputs), each of which contains the first delay element, a trigger, the first And element, and the output of the delay element is connected to the first input of the And element, the second input of which is connected to the forward output of the trigger , the inverse output and input of the device O which is connected respectively to the output of the resorption capture acknowledgment and to the input of the request for resource capture of the device channel, the trigger information input is connected to the bus of the logical unit stroystva, characterized in that, in order to increase the noise immunity; the device further comprises a pulse shaper, the first polling signal generator, an OR element, the input and output of the first pulse shaper are connected respectively to the bus unit of the device and the trigger input of the polling signal generator, the output 5 of which is connected to the first input of the OR element, the output of which is connected to the polling input of the first channel, the output of the K-th channel is connected to the second input of the first OR element, and each channel additionally contains a counterj the second delay element, the OR element, the driver of the pulses, the driver of the polling signals , entrance for-. the start of which is connected to the output of the interrogation signal generator and the installation input to the counter, the output of the second bit of which is connected to the first input of the OR element, the output of which is connected to the synchronous input 0 the trigger and the input of the first delay element, the output of the And element is connected to the input of the pulse former, the polling input of each channel of the device is connected to the counting input of the first counter, the output of the first bit of which is connected to the input of the second delay element, the output of which is connected to the second input of the IGSh element , the output of the polling signal generator is the channel output, the i-ro output (i 1, K-1) of the device channel is connected to the polling input of the (if 1) th device channel, and the polling signal generator contains the first and second elements OR delay element, one-shot, the cop and evil, and a pulse shaper 4309556 the counter, the output of the lower bit of which is connected to the input of the delay element, the output of which is connected to the first inputs of the AND element and the OR element, whose output through the pulse shaper is connected to the first input of the second OR element, the output of which is connected to the single-Q input of the torus, whose output connected to the counting counter of the counter and with the output of the interrogation signals, the input of which is connected to the second input of the second OR element, the output of the older 15 bits of the counter is connected to the second inputs of the first OR element and the remote element , Vykod is connected to the input of the installation in the ON counter. .kmn Srig.