I have the main unit.
type PDA
country Japan
ram 120 KB
The Casio SF-4900C — Electronic Personal Organiser
The Casio SF-4900C was an electronic personal organiser from Casio’s SF series — dedicated devices for managing contacts, schedules, and memos in a compact electronic format. Casio’s SF series pioneered the dedicated electronic organiser category in the mid-1980s, creating the template for personal information management that would evolve into PDAs. The SF-4900C’s combination of address book, scheduling, and memo storage in a pocket-sized battery-powered device was genuinely innovative — bringing organised personal information management to users years before PDAs made the concept mainstream.