Browse Prior Art Database

Raw Data Formatter

IP.com Disclosure Number: IPCOM000049217D
Original Publication Date: 1982-May-01
Included in the Prior Art Database: 2005-Feb-09
Document File: 3 page(s) / 75K

Publishing Venue

IBM

Related People

Roberts, MW: AUTHOR

Abstract

Prior to the implementation of the Raw Data Formatter, if the CE (customer engineer) wished to view TP (teleprocessing) line activity between valid SDLC (Synchronous Data Link Control) frames, called "idle data", it was necessary to: 1. Hand decode the trapped data in its internal machine form. 2. Use a datascope or the "PT-2", both of which are heavy, expensive, and in limited supply.

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Raw Data Formatter

Prior to the implementation of the Raw Data Formatter, if the CE (customer engineer) wished to view TP (teleprocessing) line activity between valid SDLC (Synchronous Data Link Control) frames, called "idle data", it was necessary to: 1. Hand decode the trapped data in its internal machine

form.

2. Use a datascope or the "PT-2", both of which are heavy,

expensive, and in limited supply.

In the data collected by the Internal TRAP in a computer system such as IBM System/38, there was no logical correlation between the formatted data and the internal format of the data. The CE's major problem was locating the data of interest. It was necessary to start decoding at the first byte of the data and proceed until the desired data was found. This procedure could involve searching up to 4,000,000 bytes of data (Figs. 1 and 2). Decoding this data involved the following:

1. Removing Bit 7 of every byte. That bit indicates

whether a frame was transmitted or received.

2. Decoding any Nonreturn to Zero Inverted (NRZI)

encoded

data.

3. Performing Zero Bit Delete by deleting the 0

following

every five consecutive 1 bits.

4. Searching for six consecutive 1 bits, which

indicates

and SDLC

Flag (there is a leading flag and a trailing

valid PDLC frame).

5. Having found a flag, blocking frames and determining

what data is the SDLC frame data and the idle data.

With the Raw Data Formatter, the CE has the ability to jump back and forth between the SDLC frame in its formatted version and the SDLC frame and its accompanying idle data. The CE can examine TP line data between SDLC frames without having to decode the internal form of the trapped data by hand.

The Raw Data Formatter presents the preceding idle data, the SDLC frame, and the following idle data in a standard dump format on a computer system, such as S/38, console. The SDLC frame is outlined by titles so it is easy to recognize which frame it is and where the frame begins and ends (Fig. 3).

Having this informa...