F-91KSD

F-91KSD is a functional and optical modification of the Casio® F-91W.

Hardware and firmware are heavily based on the brilliant pluto project.

Features

• Multiple chainable countdown timers
• Multiple alarms
• Pulsar app: tap button to measure BPMs and define LED animation
• Consistent and direct user interface
• Three bright LEDs for better readability, blinkiness, and silent alarms
• Stopwatch
• RTTTL ringtones for alarm sounds including some custom sci/fi sounds
• Extensive customisation (key beep frequency and duration, etc.)
• Watch can be calibrated (drift < 1s per month)
• Displays time in decimal/binary/hexadecimal base
• greater than 1 year battery life (estimate based on current consumption)

Differences to pluto

• New PCB (designed in Eagle)
• No compass, no IR receiver, no OTP generation
• Three LEDs including a flash light
• Different menu structure (more Casio-oriented, less menu diving)
• Chainable countdowns
• Optical alarms
• BPM measurement and optical/acoustical metronome
• Some minor bug fixes

In progress

Battery monitoring isn't functional yet.

Credits

Without previous work by carrotIndustries and sh-ow this project wouldn't exist. Most of the software components are their work.