Once upon a time, on a rainy day, gazing out from the 12th floor apartment, I found myself lost in thought fascinated by the journey of electrons through GaAsP substrates, giving birth to light. I marveled at how the first LEDs were invented and, little by little, found their way into the everyday devices we rely on today. Over time, they evolved into simple 7-segment displays, which, though now commonplace, were once cutting-edge technology, far different from the sleek, efficient displays we take for granted.

While  scrolling  through old encyclopedias and magazines, I stumbled upon some amazing golden boys of display technology: the AL304 and ALS314 7-segment and dot displays.

They look super cool and the gold is real! Back in the day, that gold was a giveaway, for hi-end electronic components.
I can't stop thinking that even the famous Predator might have had these in his DIY gadget arsenal after all, he had some pretty neat tech!

Inspired by these vintage components, I knew I had to build something with them. After scouring local markets, I managed to find a few variations of the 304 and 314 series, and the next step was choosing a suitable LED driver. The choice was obvious—I needed a common cathode LED driver. Digging through my parts bin, I had two contenders: the MAX7219 and the HT16K33. Since the HT16K33 uses I2C and also supports button functionality, I figured having some buttons would be useful. Decision made HT16K33 it was.

With their striking look, these displays deserved a worthy application. And what can be a  better match for a tiny display than a tiny Raspberry Pi?

And so, TinyNumberHat 9 was born.

As a convenience, I also decided to add a Qwiic/Stemma I2C connector. This allows the board to be connected separately, for example, to an Arduino, or to add I2C expansion boards when TinyNumberHat is mounted on a Raspberry Pi, after all, a hat should sit on a head!

I built two versions of the TinyNumberHat 9 one with red ALS314 displays and another with green AL304V which have an amazing lime-green color.
But I’m missing one AL304V, so technically, the board with the green display is now the TinyNumberHat 8.  :)

TinyNumberHat 9, populated with  ALS314, on top  of an Raspberry Pi Zero2 W:

Green Al304V:
TinyNumberHat 8 missing one AL304V to become TinyNumberHat 9