1198 - ADAFRUIT - Datasheet.Directory

timing, complete with battery backup) and a handsome laser-cut acrylic case.

These big 18-segment alphanumeric LED displays are notoriously diﬃcult to drive-- there are 54

LED elements inside each LED character and the different segments take different amounts of

current. We've now made it easy to drive ﬁve at a time, and wrapped it all up in neat package

with classic alarm-clock styling.

Standard Features of Alpha Clock Five:

Extremely wide display brightness range. All the way from very dim (for dark bedrooms) all

the way up to annoyingly bright

Huge 2.3" (5.8 cm) tall digits are easy to see,

even if you normally wear glasses

Alarm on-off indicator

Four standard alarm tones

Snooze function

12-hour (AM/PM) and 24-hour clock modes

Rear-panel white LED nightlight; can be turned on or off from the options menu

Sturdy acrylic case features subtle, laser-engraved button labels

Transparent rear panel lets you show off your handiwork

Comes complete with plug-in power supply and backup battery

Microcontroller comes pre-programmmed; no programming is required

Hacker-friendly Design:

Open source hardware design-- easy to hack!

Open source software design-- easy to reprogram (if you want to)!

Upgradeable ﬁrmware

Based on the ATmega644A microcontroller with 64 kB of ﬂash, with plenty of room to

grow.

Comes pre-ﬂashed with Sanguino bootloader; can be programmed through Arduino IDE

(with extensions).

6-pin TTL-serial connector, can be used to display data or time sent from computer

Unused I/O pins are broken out from the microcontroller, including one ADC and 5+ GPIO

Open-frame case design gives easy access to serial connector and reset button

Alpha Clock Five kit conﬁgurations:

The full (non-basic) Alpha Clock Five kit-- available on this page --comes complete with the

beautifully made Alpha Clock circuit board, the ﬁve alphanumeric LED displays (ultrabright

white, 2.3" character height, with upper and lower decimal points), machine pin sockets for

those displays, pre-programmed ATmega644A microcontroller with Sanguino bootloader, 5

tactile button switches, 20 ppm quartz crystal, universal-input plug-in power supply, stainless

mounting hardware, alarm buzzer, all of the the LED driver chips, transistors, resistors,

capacitors and other little parts needed to build the kit, plus a Chronodot real-time-clock

module and a handsome laser-cut acrylic case.

The Alpha Clock circuit board is 9.430 X 2.736" in overall size, and extra stiff at 0.094" thick. It

has a black soldermask and gold plated ﬁnish. Once assembled with its case, Alpha Clock Five

is approximately 9.44" wide, 3.78" tall, and 2.80" deep.

ChronoDot

Alpha Clock Five comes complete with a Chronodot real-time clock module. It provides your

clock kit with (1) a higher accuracy quartz crystal oscillator, (2) a backup battery, and (3) extra

geek cred for having a TCXO-based RTC. The included battery is estimated to last for 7 years.

USB-TTL Cable

You may be interested to add an optional FTDI USB-TTL converter cable, which provides an

optional interface between your computer and your clock. It can be used (1) to sync the clock's

time to the time on your PC, (2) to reprogram the clock through (a modiﬁed version of) the

Arduino IDE, or (3) to send serial data to display on the ﬁve-character LED display. Note,

however, that these are entirely optional operations-- no programming is needed to build or use

an Alpha Clock Five clock kit!

Power supply

The Alpha Clock Five kit includes a universal-input power supply that will work with worldwide

voltages. The plug is a power-strip-friendly US type, so you may need an inexpensive "grocery

store" plug adapter to ﬁt the wall socket in your country.

If you need to provide power from an alternate source, Alpha Clock Five requires (and provides

hookup locations for) a regulated 5 V dc power supply with 1 A capacity