PCC Precision Clock Companion Web
Disconnected

Connect

Pair the browser with the clock over USB. Click Connect and pick the clock's serial port in the browser prompt.

Serial port

The Mk IV enumerates as a cu.usbmodem* device on macOS and a COM port on Windows. If this is your first connect, the browser will ask which port to grant access to — pick the one that appears when you plug the clock in.

WIP / POC

Browser port of the Mac PCC app. Work in progress, things may not work. See About for what's in and out.

Built on

Web Serial API · HTML5 Canvas · globe.gl / three.js (offline, MIT) · IndexedDB for pass history · no backend, no account, no tracking. Static files only.

Display

Drive the clock's face: mode, free text, countdowns, brightness.

Mode

Changing mode sends mode_text / mode_countdown toggles and clears the previous mode first.

Text

Longer than 10 characters scrolls as a marquee. Speed is app-side — adjust below.

Countdown

Sends countdown_to = <unix> then mode_countdown = 1.

Brightness

50%

Manual brightness persists until the clock resets. Unlock to restore ambient tracking.

Send raw command

The clock's serial protocol is key = value terminated by CRLF. See the Mk IV docs for the full command list.

Satellites

Live sky view from the clock's GNSS module. Dot colour is the constellation; fill is SNR. Sector heatmap shows peak SNR per 5° × 5° cell; trails show recent passes.

0 satellites in view

GPS fix

Status
No fix
Latitude
—
Longitude
—
Altitude
—
HDOP
—
Sats used
—
Maidenhead
—
UTC
—

Celestial

Sun alt / az
—
Moon alt / az
—
Moon phase
—
Sunrise
—
Sunset
—

Computed from the GPS-reported position and UTC time.

History

Passes
0
Today
0
Observations
0
Peak elevation
—
Longest pass
—
Azimuth coverage
0%

Legend

GPS GLONASS Galileo BeiDou

3D globe

Photographic Earth with a real day/night terminator. Satellites float above their sub-satellite points; recorded passes render as age-faded arcs. Bundled globe.gl / three.js — no external assets.

Serial monitor

Raw NMEA and command echoes from the clock. Enable NMEA to see the GNSS firehose; leave it off to watch replies to commands.

About PCC Web

Browser build of PCC — WIP / POC.

Status

Proof-of-concept. Work in progress. Things may not work. The Mac app is the supported companion.

What it does

  • Drive the clock: display modes, text, countdowns, brightness, raw commands
  • Polar sky view: sector heatmap, horizon mask, trails
  • 3D globe (shared HTML with the Mac app)
  • IndexedDB pass history with retention + time-window filter
  • GPS info, sun/moon, raw serial monitor
  • Light/dark follows the OS

What it can't

  • NTP server — no UDP listen from a browser
  • Firmware / timezone updates — no USB mass-storage mount
  • Native map — MapKit-only
  • WeatherKit — Apple-only
  • AI insights — Foundation Models are Mac-only

Links