What is it?

This item is an LED clock display designed to interface with (and power) the Raspberry Pi Zero or Zero W. It has a MAX6951 wired up to the SPI GPIO pins (for /dev/spidev0.0) and software is available for the Pi to display the current time with a granularity of a tenth of a second. Alternate software is available that will display either Greenwich Mean Sidereal Time or Local Mean Sidereal Time (if you tell it your longitude). The board has a 2.5mm jack for a 5 volt 2.5W power input, which powers both the pi and display. The pi can obtain accurate time from the Internet with NTP using whatever networking options you wish (most convenient is the new Pi Zero W with built-in WiFi).

Why did you make it?

My GPS Clock is the inspiration for this item, but sometimes getting good Internet connectivity is easier than getting good GPS reception.

What it comes with

The clock optionally comes with a Raspberry Pi Zero W and optionally a microSD card. Other networking hardware is not included. The clock board comes with a female 40 pin GPIO header. If you add a Pi Zero W, then a corresponding male header will also be included. If you order your clock assembled, then this header will be soldered onto the Pi. If you order an SD card, it will be configured with PiBakery for your WiFi network (add a note to your order with the SSID and WPA passphrase) or Ethernet (Ethernet hardware not included). On its first boot, it will download and install the clock daemon, so Internet connectivity must be available.

A laser-cut wood and acrylic case is also available. The case has a knock-out panel that can be removed to expose the GPIO header. If you order your clock assembled, then it will be assembled in the case (assembly is only available when a Pi Zero W is included in your order). Otherwise, it includes all laser-cut parts and hardware required.

GPS add-on

You can configure your Raspberry Pi Zero clock as a GPS equipped stratum 1 NTP server with the Raspberry Pi variant of our GPS Breakout Board. See the Hackaday Project for more details.