SU1275422A1 - Address selector for input-output cassette - Google Patents

Abstract

The invention relates to automation and computer technology and can be used in SIC; I / O topics of microprocessor complexes that control the operation of technological equipment. The circuit of the invention is the expansion of the field of application of the address selector by providing the possibility of working with input-output cassettes of various sizes. It contains an adder and a comparison unit. At the inputs of the adder, codes are received that determine the initial physical address and the size (interval of addresses) of the I / O cassette with which the selector is connected. On the inputs of the adder, the initial physical address of the next I / O cassette is generated. The compare unit compares the I / O address code with the code of the initial physical address of this cassette and the code at the outputs of the adder. If the input-output address code belongs to the interval of the physical addresses of this cassette, then the output of the comparison block (selector cassette selection output) appears with a signal permitting the given cassette (In the input-output network, information can be exchanged. The initial physical address of the first cassette can be for example, a zero connection is specified (their input of the adder is connected to ground. The initial physical addresses of the following set5 are set automatically when the power is turned on. 3 Il. SP tsD

Description

The invention relates to automation and computer technology and can be used in input systems of microprocessor complexes controlling process equipment.

The aim of the invention is to expand the scope of the address selector by providing the ability to work with input-output cassettes of various sizes.

FIG. 1 shows the block diagram of the address selector; 2, an example of using an address selector in a programmable controller I / O system; on 4 mg. 3 is a variant of a specific implementation of a selector on 564 series microcircuits.

The selector contains an adder 1, a comparison unit 2, inputs 3 of the selector cassette number, inputs 4 of the selector cassette size, selector address inputs 5, outputs of the selector cassette number b, output 7 of the selector cassette selection. FIG. 2 denotes an I / O cassette address selector 8 and processor 9.

The address selector works in the following PTS1M manner.

A binary code is entered at the inputs 3 of the selector, which determines the starting physical address of the given I / O cassette in the address space of the I / O system. A binary code is applied to the inputs 4 of the selector that determines the size of the cassette, i.e. the size of the memory area occupied by this cassette in the address space of the I / O system. Specifically, the size code is determined by the number of I / O channels or I / O ports located in the cassette. At outputs 6 of adder 1, the initial physical address of the next I / O cassette is generated. The inputs 5 of each selector 8 receives the I / O address code generated by the processor 9. Block 2 compares this code with the code at inputs 3 of the selector and with the code at the outputs

adder 1. If the address code at inputs 5 is greater than or equal to the code at inputs 3 and less than the code at the outputs of adder 1, then at output 7 of the selector a signal appears that allows this input / output cassette to exchange information with the processor 8. Initial physical address first the cassettes can be set to zero, for example by connecting the inputs 3 of the selector 8

first cassette to the ground. The initial physical addresses of the next cassettes are set automatically when the power is turned on.

Thus, the proposed selector allows the use of cassettes of different sizes in the input-output system of the cassette.

Claims (1)

Invention Formula The address selector of the I / O cassette containing the adder and the comparison unit, the inputs of the adder of the first group are combined with the inputs of the second groups of the comparison block and are the inputs of the selector cassette number, the outputs of the adder are the outputs of the selector cassette number, the inputs of the first group of the comparison block are address inputs of the selector, the output of the comparison unit is the output of the selection of the selector cassette, characterized in that, in order to expand the field of application of the selector due to the possibility of working with different size cassettes, the adder outputs are connected to the inputs of the third group of the comparison unit, and the inputs adder groups are selector cassette size inputs. phi2.1 Shchi2.2