Hitachi HPW-200EC - Manual (Page 23)

To change ROM board
If upgrade ROM board released, you can change ROM board to up-
grade. Please take the same procedure as "To put additional RAM
board " and change ROM board.
Backup all data in your Handheld PC to desktop PC before you
perform to change ROM board, otherwise all data in your Handheld
PC will be erased.
Caution
ROM Connector
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