OpClock

UTC Date and Time clock with event feed designed for co-ordinating spacecraft operations.

This software has been developed with the official Raspberry Pi 7" touchscreen and a Raspberry Pi 4, and Raspberry Pi OS Lite (64-bit) (Bullseye.)

Dependencies

sudo apt install build-essential libcurl4-openssl-dev

Configuration

Copy config.ini.template to config.ini and customise.

Compile and Install

make
sudo systemctl enable systemd-time-wait-sync
sudo ./install

Raspberry Pi Modifications for fast & graphically-clean boot

sudo systemctl disable getty@tty1.service

/boot/config.txt:

Comment out the line: dtoverlay=vc4-fkms-v3d
Append the following lines:

disable_splash=1
boot_delay=0
dtoverlay=pi3-disable-bt

Optional, requires RPi4(?) and UHS-1 SD Card, append the line: dtoverlay=sdtweak,overclock_50=100

/boot/cmdline.txt

Remove console=tty1
Append vt.global_cursor_default=0 logo.nologo

Usage

Reboot to apply the boot modifications and let the clock start automatically.

Waiting for Network & Time Sync on boot

As the Raspberry Pi has no RTC the clock will not start until systemd reports that the system time has been synchronised by NTP. This means that networking and NTP need to be configured correctly and be available for the clock application to start.

Backlight On/Off Control

You can switch off the display backlight by double-tapping the touchscreen anywhere. A single tap anywhere will then switch the backlight back on.

HTTP Events Endpoint

When configured for the HTTP/HTTPS endpoint, the application expects the endpoint to return a JSON structure containing:

{
       "events": [
              {
                     'description': 'AoS ISS',
                     'type': 2,
                     'time_unix': 1524382363
              },
              ...
       ]
}

An example endpoint is served on https://localhost:4443/ by the python3 script in test-http-endpoint, this can be run by:

cd test-http-endpoint
./test-http-endpoint.py

This test script will generate events for the next few minutes when first started, so needs to be restarted regularly for fresh events to be available for the display.

Event Types

A few numeric event types are implemented to render simple highlight graphics on the display.

TYPE_NONE = 0 (No graphic)
TYPE_DOWNLINK_START = 1 (blue ramp-up)
TYPE_DOWNLINK_STOP = 2 (blue ramp-down)
TYPE_UPLINK_START = 3 (yellow ramp-up)
TYPE_UPLINK_STOP = 4 (yellow ramp-down)

Licensing

Unless otherwise specified at the top of the relevant file, all materials of this project are licensed under the BSD 3-clause License (New BSD License).

philcrump/rpi-opclock