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Line Adapter Configuration for Fault Location

IP.com Disclosure Number: IPCOM000090722D
Original Publication Date: 1969-Jun-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 51K

Publishing Venue

IBM

Related People

Maholick, AW: AUTHOR [+2]

Abstract

A line adapter for connection between a central processing unit CPU and a communications line is used to assemble or disassemble the bits of a character and to convert signal levels between the CPU and the communications line. The section of the line adapter enables the CPU to run diagnostic tests of the adapter to determine the source of detected errors.

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Line Adapter Configuration for Fault Location

A line adapter for connection between a central processing unit CPU and a communications line is used to assemble or disassemble the bits of a character and to convert signal levels between the CPU and the communications line. The section of the line adapter enables the CPU to run diagnostic tests of the adapter to determine the source of detected errors.

CPU 10 contains the program and hardware to control the normal functions of the line adapter and transmits control words to A control register 11 or B control register 12 over control bus 13. The setting and resetting of the individual stages of registers 11 and 12 completely determines the functions of the line adapter. Normally in transmit operations, CPU 10 sends a character on Data Out bus 15 into B register 16. This acts as a buffer and transmits the stored character over bus 19 into A register 17 which shifts it out bit-by-bit to transmit line 18.

In receiving, bits are received in B register 16 over line 21 and assembled into characters which are transferred over bus 19 to A register 17. This acts as a buffer and sends the characters out to CPU 10 over Data In bus 22 upon a CPU 10 request. CPU 10 is continuously informed of the condition of the essential adapter hardware over busses 24 and 25 which diverge in the adapter to the control structures. Shift register 27 in the line adapter controls such adapter for the different phases of reception of data and for...