SU1334152A1 - Device for simulating input-output port - Google Patents

Abstract

. The invention relates to computing and can be used in a digital computer with a backbone structure for receiving and transmitting information. The aim of the invention is to reduce the hardware cost of the device. The device contains a selector 1, trigger 2, and register 3. When a new I / O port is introduced into digital computer 4, the device allows to emulate its operation. 1 il. (L with SA SP 1chE

Description

The invention relates to computing and can be used in digital computers with a backbone structure of information receiving and transmitting routes for emulating input / output ports.

cvm. The purpose of the invention is to reduce the hardware cost of the device.

The drawing shows a block diagram of the device.

The device contains a selector 1, trigger 2, register 3 and digital computers 4.

The device works as follows.

When the power of the digital computer is turned on, the zero input of the trigger 2 is given a reset signal and the trigger 2 is set to the zero state

At the setup stage, the control input of the selector 1 is supplied with the constant of the base address of the device.

When the digital computer accesses the device, the address received at the information input of the selector 1 and specified at the control input of the selector 1 is compared and when it coincides. At the second output: the selector excites the signal coming at the input of the exchange of the digital computer and prevents the processor from stopping. TsVM By the same signal, information at the information input of the register 3 is written to it. In addition, this signal establishes in state one trigger 2, the signal from the output of which is fed to the interrupt input of the digital computer, On the interrupt signal of the digital computer it goes to the pre-processing program

Compiled by C, Vurukhin Editor E, Kopcha Tehred I.Popovich Proofreader - Demchik

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Circulation 672 Subscription

VNSHPI State Committee of the USSR

for inventions and discoveries 113035., Moscow, Zh-358 Raushsk nab ,, d, 4/5

Production and printing company, Uzhgorod, st. Project, 4

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five

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digging and changing the address at the input of the selector 1. At the first output of the selector 1, a signal is excited, resetting trigger 2 to the zero state and removing the interrupt signal,

Subsequently, the operation of the I / O port, which is accessed, is emulated by a digital computer subroutine, whose address is found on the data bus from register 3,

Claims (1)

Invention Formula Device for imitation of port of input. The containing selector, trigger and register, with the information input of the selector connected to the input of the device for connecting the address output of the digital computer and to the information input of the register, the output of the trigger connected to the output of the device for connecting. The digital input interrupt input, the selector control input is connected to the device’s base address constant input, I distinguish that, in order to reduce hardware costs, the first selector output is connected to the zero trigger input and to the device input to connect the digital output installation, the second the output of the selector is connected to a single trigger input, a register synchronization input and a device output for connecting to the confirmation input of a digital computer, the register output is connected to a device output for connecting a digital computer data input, ..