Can PC software directly manage data on the Casio digital diary through the serial link?
Not on the standard SF models. The Casio communications interface does not include any remote command capability. PC software like CASIF/Win cannot change the contents of the Digital Diary in any way, other than to load new data items. It cannot delete or edit items in the Digital Diary memory. It cannot mark or unmark data items in the Digital Diary. It cannot switch between different memory areas. It cannot read or write the letter memories, the Secret password, Home or World time, Daylight Savings Time settings, changes to default field names, or System settings. The newer SY models which support a Synch function do allow the PC to update and delete data items on the diary. Refer to Synchronizing Data.