Shared Projects by RafaelRiber

The Retro|Watch V2 is based around the HP QDSP-6064 Bubble display, used in 70s HP calculators like the HP-35. The display is controlled by an Atmel ATMega328U4 MCU with Arduino code and flashed with an Adafruit Feather 32U4 bootloader, and the time is kept by a Maxim DS3231 Real-Time Clock module, that stays connected to the LiPo battery at all times, keeping time even when the microcontroller and display are not powered. This second version of the watch uses another microcontroller, the ATMega32U4, for USB capability, and a battery recharge circuit for USB Charging. In order to fit all that added circuitry, smaller components as 0603 resistors and a QFN chip were used. THIS MAKES ASSEMBLY CONSIDERABLY HARDER THAN V1, and is not recommended for beginners.

Tested and working !

A retro watch, based around the HP QDSP-6064 Bubble display, used in 70s HP calculators like the HP-35. The display is controlled by an Atmel ATMega328P-AU MCU with Arduino code, and the time is kept by a Maxim DS3231 Real-Time Clock module, that stays connected to the LiPo battery at all times, keeping time even when the microcontroller and display are not powered.

The code and design files for this watch are fully open-source, and available on GitHub.

(DISCLAIMER: I am in no way affiliated with Atmel. I just put the Atmel logo on the PCB to show the circuit uses an Atmel chip, which I really like !)

Breakout for the Atmel ATTiny85-20SU. Fits perfectly on a breadboard.