Browse Prior Art Database

Production of Special Sequences by Using Transparent Mode

IP.com Disclosure Number: IPCOM000036346D
Original Publication Date: 1989-Sep-01
Included in the Prior Art Database: 2005-Jan-28
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Bailey, RN: AUTHOR [+3]

Abstract

In building an adapter to control a serial link running the protocols as defined by PKD081102 - The Serial I/O Architecture, one of the required functions is the ability to transmit continuous streams of two-character sequences. These sequences are used for link initialization and recovery from errors that occasionally occur on the data links. The serial adapter has an existing method whereby data can be sent by the adapter without being encoded.

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Production of Special Sequences by Using Transparent Mode

In building an adapter to control a serial link running the protocols as defined by PKD081102 - The Serial I/O Architecture, one of the required functions is the ability to transmit continuous streams of two-character sequences. These sequences are used for link initialization and recovery from errors that occasionally occur on the data links. The serial adapter has an existing method whereby data can be sent by the adapter without being encoded.

This special mode of operation, called transparent mode, allows a fixed-size buffer full of data to be sent. This disclosure adds to this mode of operation the capability of repeating that operation automatically so that a continuous sequence is formed. Since the buffer can be any data whatsoever, any present or future architected sequence can be sent.

The operation once started will continue until an ending condition occurs on the transmit or receive link, or the programmer issues a halt or cancel command. The programming rules have been changed to allow the first transparent-mode character to be any +2 disparity character (any ten-bit character with two more 1 bits than 0 bits) or an even disparity character (any ten-bit character with the same number of 1's and 0's) if followed by a + disparity character. The success of this method, providing a valid continuous sequence, depends on the fact that a full buffer contains an even number of two-character sequences s...