Status: Accepted · Recorded: 2026-11

Amends ADR 0060 (point 4, and the consequence that leaves entities and automatic subscription to later decisions). Follows the pattern of ADR 0050 and amends its miss rule (point 6 below), since the rain poll shares the schedule.

Context

A Somfy RS100 Solar io motor answers a subscription (0x73 01 <event>) at once with a 0x71 carrying the event's current value (issue #156):

event 0x2005 carries a sun value: 06 00 <hi> <lo> B9, 0 at night, 183 and 744 in daylight (corpus somfy_rs100_probe_subscribe_event_sx1262 and somfy_rs100_probe_subscribe_event_daylight_sx1262). The motor stores the same number in its power record (somfy_rs100_probe_read_object_a601_sx1262);
event 0x2001 carries one byte, 100, while the status byte's battery field reads full (somfy_rs100_probe_subscribe_event_battery_sx1262).

The motor has never sent either event on its own in any log from that issue, so a subscription that waits for reports would show nothing. Over one afternoon the reporter subscribed every 20 minutes: 15 of 21 subscriptions were answered. The other six got no answer at all: in five the motor took the request and sent its challenge but no answer followed; in one it never woke. Inside each exchange, a second try after a silent first one was answered in six of nine cases. The answer to the subscription is the only way the value arrives, and it costs one exchange. The motor accepted every repeated subscription it was sent (more than five to 0x2005 over a week, one to 0x2001).

Three existing rules stood in the way:

ADR 0060 never sends an accepted subscription twice ("a second accepted copy has no use");
the hub treats any event report arriving inside an exchange as not the reply, records it and asks again (ADR 0060's amendment);
and ADR 0060 left an entity for the reports to a later decision.

Options considered

Wait for pushed reports after one subscription. Rejected: none has ever been seen.
Read the motor's power record with the data-transport read (ADR 0062). Rejected for a periodic sensor: about 25 exchanges and 30 seconds of blocked loop per read, against one exchange.
Re-send the subscription periodically and read its answer (chosen).
A separate schedule class per sensor. Rejected: the rain poll's schedule (RainPollPolicy) had nothing rain-specific but its name; it becomes PeriodicPollPolicy, one instance per poll.

Decision

Two opt-in cover keys, no default:
- sun_level_poll_interval creates <Cover Name> Sun level, a sensor with no unit and no device class, published raw;
- battery_level_poll_interval creates <Cover Name> Battery level, a % sensor with device class battery.
Each key schedules its own poll; a cover without it is never polled and gets no entity. The minimum is one minute, as for the rain poll.
The poll is the subscription. create_subscribe_event() with its existing two-event allowlist builds the request; the answer is the reading. Every poll subscribes again.
The answer is the reply. decisions::is_subscription_answer() accepts a well-formed 0x71 carrying the subscribed event from the addressed device as the reply to that request. Every other event report keeps ADR 0060's handling: recorded, never applied, request asked again. The poll's own answer is not put on the Last Device Event sensor.
One re-send after an accepted, unanswered try (UNCONFIRMED_SUBSCRIBE_MAX_RESENDS, for the probe as well as the poll). This replaces ADR 0060 point 4: the answer carries the reading, so a lost answer is worth one more copy, and the device accepts repeats.
Strict decode. decode_sun_level_event() accepts only the captured shape (5 data bytes, first byte 06, value in bytes 2–3); decode_battery_level_event() only one byte up to 100. Any other answer is a miss, and the log names its payload once.
Same schedule rules as the rain poll (ADR 0050):
- the first poll comes 15 to 45 s after boot, then every interval ±10 %;
- a moving device is asked again 30 s later;
- a poll the device leaves unanswered (silence, or a challenge with no answer) is asked once more 60 s later (PERIODIC_POLL_MISS_RETRY_MS), and counts as a miss only if the retry is unanswered too. An error reply or an answer of another shape counts at once, since asking again soon would not change it. This applies to the rain poll as well and amends ADR 0050's "three consecutive unanswered polls";
- the reading goes unknown after three consecutive misses;
- it is a background operation, and pairing flushes it;
- a miss counts in Exchange Failures, never in the status poll's backoff.
Pushed reports stay unapplied. A 0x71 with these events that arrives on its own is still only recorded (ADR 0060 point 5).

Consequences

Each poll writes the subscription into the device again. Nothing so far says the device keeps more than one entry per controller, but that is not known. The documentation says so plainly.
Transmit time is the user's choice, as for rain. On a low_power motor each poll carries the long wake-up preamble, often twice, so a one-minute sun poll costs several times the hourly allowance of the 868.95 MHz band; the documentation gives the cost per interval and recommends values, and the hub enforces only the one-minute floor.
A missed poll costs one more exchange a minute later. At the RS100's miss rate (about one poll in four) that adds about a quarter to the poll's transmit time. In exchange, a slot ends without a reading only when two polls a minute apart both fail. Replayed against the reporter's afternoon, that turns a sun level that would go unknown about once a day at a 30-minute interval into one that almost never does. A retried slot moves the schedule by one minute.
The sun value has no unit. Publishing it raw means adding a unit later is not a breaking change; a converted value would be a new entity.
Percent rests on one value (100). A level below 100 has not been captured.
Confirmed on one device. Both sensors are experimental: one Somfy RS100 Solar io, one reporter. Other devices may refuse the subscription or answer in another shape; their sensors then stay unknown.
battery: true is unchanged. It reads the coarse full/normal/low level from status replies at no radio cost and stays the low-battery signal.