11 · Changelog

1.3.0 (2026-06-16) — Public release

First public release of the rbamp component for ESP-IDF v5.x.

Fleet manager: manage a group of modules on a single I²C bus through a single rbamp_fleet_t handle. Discovery with conflict detection and Tier-2 wedge canary, MISS-resilient _poll_all, aggregation of total-power / total-energy / errors, broadcast-latch for billing-grade synchrony. See chapter 09 · API Reference, section "Fleet manager".
Provisioning: rbamp_provision — a single-call workflow for reassigning a virgin module to its working address, with optional persistence of the configuration to flash. Discipline: one virgin at a time on the bus (a normative MUST).
Multi-channel configuration: rbamp_configure_channels — atomic per-channel setup of CT models in a single operation with a single terminal flash cycle (flash-friendly).
Error model v1.3: separates the last-write-outcome (REG_ERROR (0x02) — synchronous channel, validated by setters) from the durable async signal (EVENT_FLAGS.bit3 — sticky, for runtime facts). The corresponding functions are rbamp_read_last_error, rbamp_has_error, rbamp_clear_error, rbamp_read_event_flags.
Identity / feature-detect: rbamp_read_variant, rbamp_read_capability (12-bit map), rbamp_has_voltage, rbamp_read_product_id, rbamp_read_uid, rbamp_is_provisioned.

Multi-module topology is the library's primary operating mode. The "one module on the bus" scenario is the minimal case, not the canon. The canonical deployment is a mains module at the service entrance plus N modules on individual loads, all on a single I²C bus under a single fleet handle.
Supported SKUs on current hardware: UI1 (mains meter: voltage + current + power + PF + energy), I1 / I2 / I3 (sub-meters: current only, per channel). UI2 / UI3 are on the roadmap.
Energy and power are computed only on UI variants (which have a voltage front-end). On I variants, rbamp_read_power / _power_factor return 0.0f; fleet aggregation of total-power / energy correctly sums and ignores the zero contributions.
CT-binding is pure-staging (v1.3 canon): writing REG_CT_MODEL does NOT apply the value automatically; binding happens through the per-channel CMD_SET_CT_MODEL_CHn. The binding order is arbitrary (the "ascending/descending order" anachronisms from pre-v1.3 have been removed).
Address change is production-OK: two-phase commit + magic + reset works in production (no develop-mode required).
Master wall-clock = canonical timebase for Wh: the chip software timer PERIOD_LATCH_MS (0xEC) is diagnostic-only and may underreport by up to 25-30% under load (SysTick starvation by design). The master uses its own esp_timer_get_time() or wall-clock for billing.

01_overview — lead reworked to be multi-module-first; added an ASCII diagram of the 80% scenario.
03_sensor_selection — sweep on CT order; new section "Multi-channel modules — I2 and I3 (current-only)" with a UI1+I3 disaggregation pattern.
04_hardware — the section "Multi-module bus — primary topology" promoted to the main operating mode; explicit requirement for external ~4.7 kΩ pull-ups on the fleet bus; provisioning workflow via rbamp_provision.
09_api_reference — added sections: "Identity and provisioning", "Error model v1.3", "Multi-channel configuration", "Fleet manager — managing multiple modules", "Per-device fleet config".
10_troubleshooting — added sections "IDF i2c_master hangs on a marginal bus — three-layer mitigation" (with an HW-validated hang-rate table), "Fleet: a module ended up excluded", "Fleet: rbamp_fleet_scan returned INVALID_STATE", "Fleet: rbamp_provision returned an error".
11_changelog — this file.