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Method to Allow Transfer of a 3-1/2" 80 Track Diskette Through the VM Network

IP.com Disclosure Number: IPCOM000039223D
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-01
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Lin, C: AUTHOR [+2]

Abstract

A method is described to transfer 3-1/2" 80-track diskettes to countries through the VM network. Either the 40-track or double density 80-track diskette files could be transmitted to other PCs or terminals using VM commands, through the VM network. If a user wants to transfer a 3-1/2" 80-track diskette, there must be some conversions in order to make use of the existing VM commands. A method to convert a 3-1/2" 80-track diskette is described which also builds a checksum in to ensure the correctness of file transmission. The algorithm is described in the following 6 steps; the conversions and correctness verification are done in steps 1, 2, 5 and 6 while steps 3 and 4 are done by VM commands. Step 1. Read the entire diskette from a 3-1/2" 80-track diskette drive to create a diskette file.

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Method to Allow Transfer of a 3-1/2" 80 Track Diskette Through the VM Network

A method is described to transfer 3-1/2" 80-track diskettes to countries through the VM network. Either the 40-track or double density 80-track diskette files could be transmitted to other PCs or terminals using VM commands, through the VM network. If a user wants to transfer a 3-1/2" 80-track diskette, there must be some conversions in order to make use of the existing VM commands. A method to convert a 3-1/2" 80-track diskette is described which also builds a checksum in to ensure the correctness of file transmission.

The algorithm is described in the following 6 steps; the conversions and correctness verification are done in steps 1, 2, 5 and 6 while steps 3 and 4 are done by VM commands. Step 1. Read the entire diskette from a 3-1/2"

80-track diskette

drive to create a diskette file.

Step 2. The 2-byte checksum is also accumulated

during reading

(the diskette) from the 3-1/2" 80-track

diskette drive and then written to the last

two bytes as separate data in the diskette

file.

Step 3. Transmit this diskette file to another PC

with a 3-1/2"

diskette drive attached, using VM commands,

through the VM network.

Step 4. Write the file from the VM virtual disk to a

PC diskette

file, using VM command.

Step 5. Convert the diskette file to a 3-1/2"

80-track diskette.

Step 6. Accumulate the checksum during conversion of

the file

and have this accumulated checksum compared

with the checksum data...