Nixie tube clock with Atmel AVR ATtiny2313 microcontroller

This site contains notes and alternative ATtiny2313 firmware (including commented C sources) for Stanislav Pechal's nixie clock construction from PE1/2008 [1].

Image gallery

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Alternative firmware

• 2008-02-01 nixie_pechal_20080201_ch.zip
• new: alarm snoozing logic (manual snooze on KEY_UP button / autosnooze on no user response to alarm)
• new: alarm stop button (KEY_ENTER). Mutes alarm and keeps it scheduled on next day.
• new: editable alarm on/off flag via rightmost digit "0"/"1" on alarm setting menu (hw buzzer switch no more required)
• new: actual alarm time indication. Actual alarm time flashes on display for few seconds after snooze/autosnooze/alarm-stop action.
• code: 1538 B (+ 460 B), data: 53 B (+ 9 B)
• 2008-01-30 nixie_pechal_20080130_ch.zip
• fix: delay loops via _delay_ms() (util/delay.h) instead of for(;;) (optimizer changes semantics otherwise)
• fix: globals, being modified inside interrupt handler are declared "volatile" (optimizer changes semantics otherwise)
• new: CPU clock reduced 32x to 375 kHz (XTAL 12 MHz with 32x prescale) => 7x lower current req.
• new: button click sound
• code: 1078 B, data: 44 B
• 2008-01-01 nixie_pechal_20080101.zip
• original firmware by Stanislav Pechal [1][2]

References