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Browse Prior Art Database

Updating Vital Product Data Information in Flash Eprom without Erasing

IP.com Disclosure Number: IPCOM000103452D
Original Publication Date: 1990-Nov-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 56K

Publishing Venue

IBM

Related People

Comp, CM: AUTHOR

Abstract

Described is a method for updating vital product information in a flash eprom without having to erase the entire device.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 63% of the total text.

Updating Vital Product Data Information in Flash Eprom without Erasing

      Described is a method for updating vital product information in
a flash eprom without having to erase the entire device.

      Vital Products Data (VPD) is stored on each Input/Output
Processor (IOP) card in a flash eprom device along with the code
required by the on card microprocessor. VPD information stored
includes part numbers, manufacturing location, serial numbers, etc.
This information is written into the eprom device when it is first
tested at the card tester.  If the VPD information changes during
manufacturing, the flash eprom will need to be updated.

      To update only the VPD the flash eprom normally requires the
whole device to be erased, and then completely reprogrammed.  This
additional time increases the card test time, and thus the cost to
test the card.

      To shorten the time to update only the VPD information a new
procedure was created.  The flash eprom device memory bits when
erased will contain all '1's.  When programming the device, only bit
locations with a value of '1' can be changed to '0'.  To change a '0'
to a '1' requires the entire device to be erased and reprogrammed.

      A new idea to have multiple VPD entries in the flash eprom is
described.  The number of entries would depend on the unused portion
of the flash eprom.  Each entry would contain the norm VPD
information and a byte to indicate the status of the entry.  After
eras...