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CardSat v0.9.21

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@prstoetzer prstoetzer released this 19 Jun 22:32
· 10 commits to main since this release
0.9.21
8153366

An IR pass-alert beacon: the built-in IR LED now flashes on each pass-alert event,
with a distinct number of flashes per event, so you can build your own
IR-triggered hardware.

Hardware status. Host-verified only (tokenizer-balanced; the carrier timing
and flash-count state machine compiled with mocks and checked off-device). The
actual IR output and a receiver decoding it have not been confirmed on a device —
verify before relying on it.

IR pass beacon (build-your-own trigger)

Enable Settings → Station → IR pass beacon (off by default) and CardSat will
flash the Cardputer's built-in IR LED (GPIO 44) on every existing pass-alert event,
in addition to the usual beeps. Each event sends a distinct number of flashes:

Event Flashes
T-60 s to AOS 1
T-30 s to AOS 2
T-10 s to AOS 3
AOS (pass start) 4
TCA (peak elevation) 5
LOS (pass end) 6

Each flash is a ~60 ms burst of standard 38 kHz IR carrier with ~140 ms gaps —
the kind any common IR receiver/demodulator (TSOP38238, TSOP4838, etc.) detects.
CardSat only transmits the counts; the receiving side is yours to design. Point
a 38 kHz receiver at the Cardputer, count the pulses, and trigger whatever you want:
power up a rotator/preamp at T-10, flash a shack light at AOS, start an SDR
recording, drive a louder external alert, or log events on a second microcontroller.

The flashing is fully non-blocking — one burst at a time between the normal
tracking updates — so radio, rotator, and web control keep running throughout. It's
gated by the AOS-alarm system, so it only fires when the AOS alarm is on.

Host-verified only. The 38 kHz carrier, duty cycle, and burst/gap timing may need
tuning for your particular receiver; treat the flash counts as the stable
contract and the exact waveform as adjustable. The feature uses only GPIO 44 (the
built-in IR LED) and is off until you enable it.

Notes

  • All host-verified only. The IR carrier generation (LEDC PWM at 38 kHz, gated per
    burst) and the flash state machine were checked off-device (balance + g++
    semantic compile + a mock-clock run of every flash count), but on-device
    confirmation — that a real IR receiver sees and counts the bursts — is still
    needed.
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