feat: v2.4.0 — Basic Endpoint Types II: I2C, UART, ADC, PWM_OUT, PWM_IN

.fusa-reqs.json

@@ -3151,6 +3151,206 @@
       "standard": "iso26262",
       "level": "ASIL-B",
       "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-I2C-001",
+      "title": "i2c_mode open item \u2014 coarse high-speed decode only",
+      "text": "rcp::i2c::i2c_mode_of shall map AcfMessageInfo::hs=false to I2cMode::Standard and hs=true to I2cMode::HighSpeed, and shall not attempt to distinguish any finer I2C speed grade, per this milestone's documented open item pending a future spec errata pass.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-I2C-002",
+      "title": "I2C compound-wait arbitrary-bit-sequence match",
+      "text": "rcp::i2c::compound_wait_matches_bits shall compare exactly the leading `bit_len` bits of `received` against `expected` (MSB-first within a byte, comparing only the top `bit_len % 8` bits of a partial final byte), shall return false when either buffer is shorter than `bit_len` requires, and shall return false for `bit_len == 0`.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-I2C-003",
+      "title": "I2C controller-only raw byte-stream transfer",
+      "text": "rcp::i2c::I2cEndpoint::transfer shall record the exact byte sequences passed as `out_bytes` and `in_bytes` \u2014 including any address byte(s) the caller embeds in `out_bytes` \u2014 retrievable via last_sent()/last_received().",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-I2C-004",
+      "title": "I2C TransferComplete and Nack trigger signals",
+      "text": "rcp::i2c::I2cEndpoint::transfer shall notify TransferComplete on every transfer, shall additionally notify Nack and return I2cErrc::nack when called with acked=false, and shall notify only TransferComplete for an acknowledged transfer.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-I2C-005",
+      "title": "I2cErrc is a distinct error category with a non-empty message",
+      "text": "rcp::i2c::make_error_code(I2cErrc::nack) shall report rcp::i2c::i2c_category() as its category and shall have a non-empty diagnostic message.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-UART-001",
+      "title": "UART TX queue is independent of the RX FIFO",
+      "text": "rcp::uart::UartEndpoint::enqueue_tx shall append to a TX queue independent of the RX FIFO's contents, drain_tx shall return and clear exactly what was queued, and enqueue_tx shall return UartErrc::tx_queue_overflow rather than partially enqueueing when the push would exceed kTxQueueCapacity.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-UART-002",
+      "title": "UART RX FIFO fill/drain semantics",
+      "text": "rcp::uart::UartEndpoint::rx_fill shall append bytes to the RX FIFO, rx_available shall report its current occupancy, and rx_fill shall return UartErrc::rx_fifo_overflow rather than partially filling when the push would exceed kRxFifoCapacity.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-UART-003",
+      "title": "UART read completion: read_size reached or uart_timeout elapsed",
+      "text": "rcp::uart::UartEndpoint::handle_read shall drain up to `read_size` bytes currently available in the RX FIFO, shall report out_timed_out=true only when read_size was not fully reached and elapsed_ms >= uart_timeout_ms, and shall return UartErrc::read_size_exceeds_bound for a read_size greater than kMaxReadSize without modifying the RX FIFO.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-UART-004",
+      "title": "UART payload-less pure read requests",
+      "text": "rcp::uart::UartEndpoint::handle_pure_read shall drain and return every byte currently buffered in the RX FIFO without waiting on read_size or uart_timeout, and shall return an empty result when the RX FIFO is empty.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-UART-005",
+      "title": "UART sub-octet bit-width padding rules",
+      "text": "rcp::uart::pack_frame_to_octet shall mask a frame's value to its low bits_per_frame bits (zero-padding the remaining high bits of the octet), rcp::uart::unpack_frame_bits shall invert that masking, and both shall return UartErrc::bits_per_frame_out_of_range for bits_per_frame outside [kMinBitsPerFrame, kMaxBitsPerFrame].",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-UART-006",
+      "title": "UART RX FIFO / read_size single-AVTPDU accepted limitation",
+      "text": "rcp::uart::kRxFifoCapacity and rcp::uart::kTxQueueCapacity shall both equal kMaxReadSize, documenting the accepted limitation that both are bounded so a UART read response always fits one unfragmented AVTPDU, consistent with ROADMAP.md milestone 52's fragmentation no-go decision.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-UART-007",
+      "title": "UartErrc is a distinct error category with a non-empty message",
+      "text": "rcp::uart::make_error_code(UartErrc::rx_fifo_overflow) shall report rcp::uart::uart_category() as its category and shall have a non-empty diagnostic message.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-ADC-001",
+      "title": "ADC arithmetic-mean averaging combinator",
+      "text": "rcp::adc::compute_average shall compute the arithmetic mean of a non-empty sample set and shall return AdcErrc::no_signal for an empty sample set.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-ADC-002",
+      "title": "ADC three-level averaging model",
+      "text": "rcp::adc::AdcEndpoint::request_reading shall average adc_avg_intervals_per_request raw samples per averaged-interval value (level 1), shall combine adc_combine_avg_values such averaged-interval values into the reported result (level 2), and shall return AdcErrc::invalid_averaging_config when either configuration field is 0.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-ADC-003",
+      "title": "ADC request-driven sampling only",
+      "text": "rcp::adc::AdcEndpoint::request_reading shall invoke its sample source exactly adc_avg_intervals_per_request * adc_combine_avg_values times per call \u2014 no more, no fewer \u2014 and shall return AdcErrc::no_signal (this endpoint's analog of PWM_IN_NO_SIGNAL on the request path) the first time the sample source reports a missing capture, without free-running or pushing samples outside a call.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-ADC-004",
+      "title": "ADC ExternalTrigger cadence pattern",
+      "text": "rcp::adc::AdcEndpoint::request_reading_from_trigger_queue shall consume exactly adc_avg_intervals_per_request * adc_combine_avg_values entries from the front of the supplied trigger-sample queue, shall erase only the consumed entries on success, and shall return AdcErrc::no_signal on a queue holding fewer entries than required.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-ADC-005",
+      "title": "ADC no-signal handling for a missing triggered capture",
+      "text": "rcp::adc::AdcEndpoint::request_reading_from_trigger_queue shall return AdcErrc::no_signal when a consumed queue entry is std::nullopt, without producing a result derived from that entry.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-ADC-006",
+      "title": "AdcErrc is a distinct error category with a non-empty message",
+      "text": "rcp::adc::make_error_code(AdcErrc::no_signal) shall report rcp::adc::adc_category() as its category and shall have a non-empty diagnostic message.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-PWM-001",
+      "title": "PWM_OUT/PWM_IN shared period/active-duration payload shape",
+      "text": "rcp::pwm::PwmValue shall default both period and active_duration to 0, and both rcp::pwm::PwmOutEndpoint and rcp::pwm::PwmInEndpoint shall operate on this same two-field type.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-PWM-002",
+      "title": "PWM_OUT write semantics: generic combinators applied independently",
+      "text": "rcp::pwm::PwmOutEndpoint::handle_write shall apply Replace/Or/And/Xor to `period` and `active_duration` independently via rcp::endpoint::apply_bitmask_write.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-PWM-003",
+      "title": "PWM_OUT write semantics: saturating Add/Subtract shared with GPIO",
+      "text": "rcp::pwm::PwmOutEndpoint::handle_write shall apply the saturating Add/Subtract rule to `period` and `active_duration` independently, clamping instead of wrapping, via the same rcp::endpoint saturation helpers rcp::gpio::apply_gpio_write uses.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-PWM-004",
+      "title": "PWM_OUT write semantics: Reserved and Reconfigure rejected",
+      "text": "rcp::pwm::PwmOutEndpoint::handle_write shall return an error without modifying its state for WriteSemantics::Reserved, and shall return rcp::endpoint::EndpointErrc::non_combinable_write_semantics for WriteSemantics::Reconfigure (PWM_OUT defines no Reconfigure target of its own).",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-PWM-005",
+      "title": "PWM_IN response-only read model and PWM_IN_NO_SIGNAL",
+      "text": "rcp::pwm::PwmInEndpoint::handle_read shall return PwmErrc::no_signal before any record_measurement call and again after clear_signal(), and shall otherwise return the most recently recorded PwmValue.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-PWM-006",
+      "title": "PWM_IN mid-pulse trigger signal",
+      "text": "rcp::pwm::PwmInEndpoint::record_measurement shall notify the MidPulse trigger signal on every call, observable via drain() only when MidPulse was armed via triggers().enable().",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
+    },
+    {
+      "id": "REQ-PWM-007",
+      "title": "PwmErrc is a distinct error category with a non-empty message",
+      "text": "rcp::pwm::make_error_code(PwmErrc::no_signal) shall report rcp::pwm::pwm_category() as its category and shall have a non-empty diagnostic message.",
+      "standard": "iso26262",
+      "level": "ASIL-B",
+      "asil": "ASIL-B"
     }
   ]
 }

CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.21)
 
 project(cpp-rcp
-    VERSION 2.3.0
+    VERSION 2.4.0
     DESCRIPTION "Remote Control Protocol for automotive zonal architecture (C++)"
     HOMEPAGE_URL "https://github.com/SoundMatt/cpp-RCP"
     LANGUAGES CXX

ROADMAP.md

@@ -361,6 +361,49 @@ lives in `tests/test_endpoint.cpp` (REQ-ENDPOINT-001..006),
 
 ### 48. Basic Endpoint Types II — I²C, UART, ADC, PWM_OUT, PWM_IN (v2.4.0)
 
+**Done (v2.4.0):** `rcp/endpoint.hpp` gains real `ep_type` id constants for
+all five endpoint types this milestone covers
+(`kEndpointTypeI2c`/`kEndpointTypeUart`/`kEndpointTypePwmOut`/
+`kEndpointTypePwmIn`/`kEndpointTypeAdc`), replacing the comment placeholder
+milestone 47 left for them. `rcp/i2c.hpp` implements I²C (`ep_type 0x04`):
+a controller-only `I2cEndpoint::transfer` recording a raw byte stream
+(address bytes included, since I²C has no separate address field in this
+milestone's scope), `compound_wait_matches_bits` implementing the
+arbitrary-bit-sequence compound-wait match (distinct from SPI's fixed
+4-of-20-byte truncation), and `i2c_mode_of` deliberately decoding only the
+coarse `hs` high-speed-requested bit — the finer `i2c_mode` speed-grade
+mapping is flagged as an open item in the header's own comments rather than
+guessed at, pending a future spec errata pass. `rcp/uart.hpp` implements
+UART (`ep_type 0x05`): independent TX/RX queues (`enqueue_tx`/`drain_tx` vs.
+`rx_fill`/`handle_read`), `handle_read`'s read-size-or-timeout completion
+rule, `handle_pure_read` for payload-less reads, and
+`pack_frame_to_octet`/`unpack_frame_bits` for sub-octet bit-width padding;
+`kMaxReadSize`/`kRxFifoCapacity`/`kTxQueueCapacity` bound both the RX FIFO
+and configurable read size to a conservative single-AVTPDU ceiling,
+documented explicitly as an accepted limitation tied to milestone 52's
+already-final fragmentation no-go decision, not left implicit. `rcp/adc.hpp`
+implements ADC (`ep_type 0x09`): `AdcEndpoint::request_reading` (SelfTimed
+cadence) and `request_reading_from_trigger_queue` (ExternalTrigger cadence,
+keyed to `rcp/pwm.hpp`'s PWM_IN mid-pulse signal) both drive the same
+three-level `compute_average` combinator
+(`adc_avg_intervals_per_request` → `adc_combine_avg_values`), request-driven
+only — sampling never free-runs outside a call — with `AdcErrc::no_signal`
+as the no-signal timeout/underrun path analogous to PWM_IN_NO_SIGNAL.
+`rcp/pwm.hpp` implements both PWM_OUT (`ep_type 0x07`) and PWM_IN
+(`ep_type 0x08`) sharing one `PwmValue{period, active_duration}` payload
+struct: `PwmOutEndpoint::handle_write` reuses `rcp::endpoint::
+apply_bitmask_write` directly (so GPIO's saturating add/subtract rule
+applies to both fields without re-derivation) and leaves Reconfigure to that
+function's own built-in rejection rather than inventing a PWM_OUT-specific
+target; `PwmInEndpoint` is response-only (`handle_read`/
+`record_measurement`), returns `PwmErrc::no_signal` (PWM_IN_NO_SIGNAL)
+before any measurement or after `clear_signal()`, and fires the MidPulse
+trigger signal `rcp/adc.hpp`'s ExternalTrigger cadence pattern is meant to
+key off of. New coverage lives in `tests/test_i2c.cpp` (REQ-I2C-001..005),
+`tests/test_uart.cpp` (REQ-UART-001..007), `tests/test_adc.cpp`
+(REQ-ADC-001..006), and `tests/test_pwm.cpp` (REQ-PWM-001..007), traced in
+`.fusa-reqs.json`.
+
 - I²C (`ep_type 0x04`): controller-only, raw byte stream including address
   bytes, compound-wait against arbitrary received-bit-sequence match; flag
   the unresolved `i2c_mode` high-speed enum ambiguity in code comments as an