{
  "$schema": "../../../tools/card-layouts/schemas/card-source.schema.json",
  "schema": "esc-card-source.v1",
  "card": {
    "id": "mpabi-freertos-c-13-uart-pipeline",
    "series": "freertos-c",
    "series_title": "FreeRTOS C",
    "number": "13",
    "count": "15",
    "slug": "uart-pipeline",
    "title": "UART interrupt-to-task pipeline",
    "topic": "bounded RX ISR, SPSC ring, task notification and frame ownership",
    "project": "Freestanding C nad FreeRTOS",
    "subject": "Informatyka",
    "level": "Rok 2 · L13 · RV32I/Hazard3",
    "revision_date": "2026-07-19T00:00:00+02:00",
    "status": "Gotowa",
    "version": "v00.01",
    "uuid": "90a3638b-63f8-5a9c-8b5e-5de4b72ac534",
    "author": "M. Pabiszczak",
    "year": "2026"
  },
  "generated": {
    "tex": "doc/generated/main.tex",
    "html": "web/index.html",
    "html_css": "web/style.css",
    "html_tree_inspector": false,
    "react_app": true
  },
  "render_dictionary": false,
  "viewpoints": [
    {
      "id": "A1",
      "label": "CONTEXT",
      "subtitle": "peripheral/ISR/task boundary",
      "status": "enabled",
      "target_label": "fig:a1-context"
    },
    {
      "id": "A2",
      "label": "STRUCTURE",
      "subtitle": "registers, ring and frame",
      "status": "enabled",
      "target_label": "fig:a2-structure"
    },
    {
      "id": "A3",
      "label": "DISPATCH",
      "subtitle": "FromISR notification",
      "status": "enabled",
      "target_label": "fig:a3-dispatch"
    },
    {
      "id": "A4",
      "label": "APPLICATION",
      "subtitle": "single pipeline",
      "status": "unavailable",
      "reason": "The concrete topology is already explicit in A1 and its ordered behavior is complete in A5."
    },
    {
      "id": "A5",
      "label": "FLOW",
      "subtitle": "valid and overflow replays",
      "status": "enabled",
      "target_label": "fig:a5-flow"
    },
    {
      "id": "A6",
      "label": "STATE",
      "subtitle": "ring and receiver states",
      "status": "enabled",
      "target_label": "fig:a6-state"
    },
    {
      "id": "A7",
      "label": "RUNTIME",
      "subtitle": "MMIO, indices, stacks and ELF",
      "status": "enabled",
      "target_label": "fig:a7-runtime"
    },
    {
      "id": "A8",
      "label": "PATTERNS",
      "subtitle": "SPSC is part of the mechanism",
      "status": "unavailable",
      "reason": "The SPSC decision is fully proved by A2 and A6; a separate pattern page would duplicate that contract."
    }
  ],
  "debug_strategies": {
    "code.contract": {
      "id": "code.contract",
      "kind": "code",
      "action": "open",
      "expected_observations": [
        "one producer and one consumer",
        "parsing absent from ISR"
      ],
      "assertions": [
        "byte is visible before head",
        "TX has one task owner"
      ],
      "evidence_fields": [
        "code_ref",
        "owner",
        "capacity",
        "budget"
      ],
      "prerequisites": [
        "FC07 and FC10 complete"
      ],
      "layout": [
        "register bank",
        "SPSC ring",
        "ISR",
        "receiver"
      ],
      "commands": [
        "rg -n 'FromISR|ring_|UART|tx_task_only' include src"
      ]
    },
    "run.pipeline": {
      "id": "run.pipeline",
      "kind": "run",
      "action": "replay",
      "expected_observations": [
        "OK newline produces ACK",
        "receiver runs before stimulus resumes"
      ],
      "assertions": [
        "ISR processes three bytes",
        "wake request is true",
        "TX count is four"
      ],
      "evidence_fields": [
        "mcause",
        "processed",
        "head",
        "tail",
        "task state"
      ],
      "prerequisites": [
        "clean Hazard3 RAM",
        "IRQ5 enabled"
      ],
      "layout": [
        "UART registers",
        "ring",
        "notification",
        "events"
      ],
      "commands": [
        "make sim",
        "print g_fc13",
        "print g_fc13_events"
      ]
    },
    "run.overflow": {
      "id": "run.overflow",
      "kind": "run",
      "action": "replay",
      "expected_observations": [
        "seven bytes queued",
        "three newest bytes dropped"
      ],
      "assertions": [
        "indices stay in range",
        "task discards partial frame"
      ],
      "evidence_fields": [
        "processed",
        "queued",
        "dropped",
        "frame_length"
      ],
      "prerequisites": [
        "first frame completed",
        "empty ring"
      ],
      "layout": [
        "ten RX bytes",
        "seven usable slots",
        "drop counter"
      ],
      "commands": [
        "break fc13_checkpoint_committed if $a0 == 8",
        "print g_fc13.ring"
      ]
    },
    "code.identity": {
      "id": "code.identity",
      "kind": "code",
      "action": "open",
      "expected_observations": [
        "C ISR and task symbols are present",
        "no C++ runtime"
      ],
      "assertions": [
        "notification implementation is linked",
        "external trap is linked"
      ],
      "evidence_fields": [
        "symbol",
        "source blob",
        "ELF SHA256",
        "image SHA256"
      ],
      "prerequisites": [
        "built ELF"
      ],
      "layout": [
        "symbols",
        "sections",
        "artifact hashes"
      ],
      "commands": [
        "make check-abi",
        "riscv64-unknown-elf-nm build/task01_uart/prog.elf"
      ]
    },
    "run.identity": {
      "id": "run.identity",
      "kind": "run",
      "action": "replay",
      "expected_observations": [
        "three identical logs",
        "digest 6089cfff"
      ],
      "assertions": [
        "PASS occurs once",
        "eleven events are ordered"
      ],
      "evidence_fields": [
        "digest",
        "event count",
        "SP",
        "artifact identity"
      ],
      "prerequisites": [
        "built image"
      ],
      "layout": [
        "three clean processes",
        "terminal digest"
      ],
      "commands": [
        "make check-determinism"
      ]
    }
  },
  "template": "templates/karta-klasyczna.json",
  "title_block": {
    "category": "KARTA PRACY · INFORMATYKA",
    "prepared_by": "M. Pabiszczak",
    "prepared_on": "2026-07-19T00:00:00+02:00",
    "title": "UART interrupt-to-task pipeline",
    "url": "https://dce7fb9d-7b2f-5d49-96a2-3a30d3070b84.mpabi.pl/6a838fd1-ab1b-52b6-baaf-659120a4d60a",
    "repository_url": "https://zsl-gitea.mpabi.pl/edu-freertos-c/lab-rv32i-freertos-c-uart",
    "url_host_uuid": "dce7fb9d-7b2f-5d49-96a2-3a30d3070b84",
    "url_domain": "mpabi.pl",
    "doc_uuid": "6a838fd1-ab1b-52b6-baaf-659120a4d60a",
    "revision": "v00.01",
    "issued_on": "2026-07-19T00:00:00+02:00",
    "series": "FREERTOS-C-13",
    "document_type": "karta pracy",
    "tool": "card-layouts",
    "show_qr": true,
    "show_repository_qr": true,
    "height_cm": 2.6,
    "repeat_on_every_page": true,
    "replace_front_matter": true
  },
  "front_page_scope": {
    "title": "Cel karty",
    "content_tex": "Uczeń buduje ograniczoną ścieżkę UART RX: ISR przenosi bajty do ringa i budzi zadanie, a zadanie składa ramki i jako jedyne posiada TX.",
    "scope_title": "Zakres karty",
    "scope_content_tex": "Dwa prawdziwe external IRQ pokazują poprawną ramkę OK oraz przepełnienie: ring o ośmiu slotach udostępnia siedem, ISR odrzuca trzy najnowsze bajty, a zadanie kasuje niepełną ramkę.",
    "scope_table": {
      "headers": [
        "Lekcja",
        "Task",
        "Najważniejsza idea",
        "Priorytet",
        "Status",
        "Version"
      ],
      "rows": [
        {
          "chapter": "FC13",
          "task": "Task01",
          "idea_tex": "bounded RX ISR, SPSC ring, task notification and frame ownership",
          "priority": "główny",
          "status": "ready",
          "version": "v00.01",
          "key": true
        }
      ]
    }
  },
  "side_margin_tree_layout": {
    "columns": [
      {
        "id": "zawodowe",
        "label": "TECH",
        "side": "left",
        "tree": "WE -> EK -> KW",
        "description": "Dowody runtime."
      },
      {
        "id": "ogolne",
        "label": "OG",
        "side": "right",
        "tree": "WE -> EN -> KW",
        "description": "Model FreeRTOS C."
      }
    ]
  },
  "learning_effects": {
    "FC13.EN01": {
      "bloom_level": "Analiza",
      "label": "UART handoff ownership",
      "text": "Uczeń rozdziela bounded ISR, SPSC data transport, notification, task parsing and TX ownership.",
      "assessment_criteria": [
        "FC13.KW01"
      ]
    },
    "FC13.EK01": {
      "bloom_level": "Zastosowanie",
      "label": "Valid frame and overflow replay",
      "text": "Uczeń odtwarza E01–E11 and proves publication order, immediate wake and drop-newest recovery.",
      "assessment_criteria": [
        "FC13.KW01"
      ]
    }
  },
  "assessment_criteria": {
    "FC13.KW01": {
      "text": "PASS; two real IRQs; ISR budget <= 10; valid ACK; seven accepted and three dropped on overflow; no index or TX ownership violation; deterministic digest.",
      "learning_effects": [
        "FC13.EN01",
        "FC13.EK01"
      ]
    }
  },
  "educational_requirements": {
    "FC13.WE01": {
      "text": "Projektowanie i badanie ograniczonej ścieżki UART od przerwania do zadania FreeRTOS C.",
      "label": "bounded RX ISR, SPSC ring, task notification and frame ownership",
      "learning_effects": [
        "FC13.EN01",
        "FC13.EK01"
      ],
      "learning_tree": {
        "schema": "we-learning-tree.v1",
        "policy": "Każda aktywna kotwica wskazuje kod lub checkpoint.",
        "ogolne": [
          {
            "effect_ref": "FC13.EN01",
            "display": "EN LOCAL RTOS.13",
            "source": "LOCAL",
            "official": "RTOS",
            "local": "13",
            "kind": "EN",
            "tree_id": "FC13.WE01.OG.LOCAL.RTOS.13",
            "text": "Uczeń rozdziela bounded ISR, SPSC data transport, notification, task parsing and TX ownership.",
            "kw": [
              {
                "criterion_ref": "FC13.KW01",
                "display": "KW LOCAL RTOS.13",
                "source": "LOCAL",
                "kind": "KW",
                "official": "RTOS",
                "local": "13",
                "text": "Łączy kod, diagram i zweryfikowany dowód."
              }
            ]
          }
        ],
        "zawodowe": [
          {
            "effect_ref": "FC13.EK01",
            "display": "EK LOCAL RTOS.13",
            "source": "LOCAL",
            "official": "RTOS",
            "local": "13",
            "kind": "EK",
            "tree_id": "FC13.WE01.TECH.LOCAL.RTOS.13",
            "text": "Uczeń odtwarza E01–E11 and proves publication order, immediate wake and drop-newest recovery.",
            "kw": [
              {
                "criterion_ref": "FC13.KW01",
                "display": "KW LOCAL RTOS.13",
                "source": "LOCAL",
                "kind": "KW",
                "official": "RTOS",
                "local": "13",
                "text": "Łączy kod, diagram i zweryfikowany dowód."
              }
            ]
          }
        ]
      }
    }
  },
  "debug_checkpoints": {
    "schema": "stem-debug-checkpoints.v1",
    "semantics": "deterministic-replay",
    "artifact": {
      "source": "src/tasks/task01_uart.c",
      "source_git_blob": "7b446e7bd4b77a01171791c15d6f534476465c46",
      "elf": "build/task01_uart/prog.elf",
      "hazard3_elf_sha256": "8a74313a087efb2b0626d5134af0c1289d21761733aba3ad4c31a837c2ab4768",
      "hazard3_image": "build/task01_uart/prog.bin",
      "hazard3_image_sha256": "2d3d44fbf0485bd4169d52ad203d50607eebfa70784f9899e20df5ad8dfb08de"
    },
    "targets": {
      "hazard3-sim": {
        "adapter": "hazard3-reset-load-replay.v1",
        "baseline": "restart-backend",
        "clean_ram": true
      }
    },
    "items": {
      "task01.configured": {
        "event_id": "E01",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 1"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13_event_count",
              "equals": 1
            },
            {
              "expr": "g_fc13_events[0].value",
              "equals": 8
            }
          ]
        }
      },
      "task01.receiver-ready": {
        "event_id": "E02",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 2"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.receiver_sp != 0",
              "equals": 1
            },
            {
              "expr": "g_fc13.good_frames",
              "equals": 0
            }
          ]
        }
      },
      "task01.good-injected": {
        "event_id": "E03",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 3"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.uart.rx_count",
              "equals": 3
            },
            {
              "expr": "g_fc13.first_done",
              "equals": 0
            }
          ]
        }
      },
      "task01.isr-entry": {
        "event_id": "E04",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 4"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.mcause",
              "equals": 2147483659
            },
            {
              "expr": "g_fc13.isr_sp != g_fc13.stimulus_sp",
              "equals": 1
            }
          ]
        }
      },
      "task01.good-isr": {
        "event_id": "E05",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 5"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.processed[0]",
              "equals": 3
            },
            {
              "expr": "g_fc13.wake_requested[0]",
              "equals": 1
            },
            {
              "expr": "g_fc13.ring.head",
              "equals": 3
            }
          ]
        }
      },
      "task01.frame": {
        "event_id": "E06",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 6"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.good_frames",
              "equals": 1
            },
            {
              "expr": "g_fc13.uart.tx_count",
              "equals": 4
            },
            {
              "expr": "g_fc13.stimulus_after_first",
              "equals": 0
            }
          ]
        }
      },
      "task01.overlong-injected": {
        "event_id": "E07",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 7"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.uart.rx_count",
              "equals": 10
            },
            {
              "expr": "g_fc13.first_done",
              "equals": 1
            }
          ]
        }
      },
      "task01.overflow-isr": {
        "event_id": "E08",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 8"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.processed[1]",
              "equals": 10
            },
            {
              "expr": "g_fc13.ring.dropped",
              "equals": 3
            },
            {
              "expr": "fc13_ring_used(&g_fc13.ring)",
              "equals": 7
            }
          ]
        }
      },
      "task01.overflow-task": {
        "event_id": "E09",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 9"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.overflow_frames",
              "equals": 1
            },
            {
              "expr": "g_fc13.frame_length",
              "equals": 0
            },
            {
              "expr": "g_fc13.ring.head == g_fc13.ring.tail",
              "equals": 1
            }
          ]
        }
      },
      "task01.stimulus-resumed": {
        "event_id": "E10",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 10"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13.second_done_at_resume",
              "equals": 1
            },
            {
              "expr": "g_fc13.stimulus_after_second",
              "equals": 1
            }
          ]
        }
      },
      "task01.pass": {
        "event_id": "E11",
        "stop": {
          "symbol": "fc13_checkpoint_committed",
          "offset": 0,
          "condition": "$a0 == 11"
        },
        "verify": {
          "expressions": [
            {
              "expr": "g_fc13_pass",
              "equals": 1
            },
            {
              "expr": "g_fc13_event_count",
              "equals": 11
            },
            {
              "expr": "g_fc13.ring.dropped",
              "equals": 3
            }
          ]
        }
      }
    }
  },
  "sections": [
    {
      "title": "A1 — Peripheral-to-task boundary",
      "order": 10,
      "content_kind": "prose",
      "asset_page_mode": "one-per-page",
      "page_orientation": "portrait",
      "content_tex": "The ISR moves available bytes and wakes a task. Framing and TX remain outside interrupt context.",
      "assets": [
        {
          "path": "assets/a1-context.png",
          "html_path": "assets/a1-context.svg",
          "source_path": "assets/a1-context.puml",
          "caption": "A1 CONTEXT — peripheral, ISR, ring, notification and receiver.",
          "label": "fig:a1-context",
          "alt": "A1 · UART responsibility boundary",
          "kind": "diagram",
          "width": 1.0,
          "page_grid": {
            "columns": 1,
            "rows": 1,
            "page_width": 660,
            "page_height": 760,
            "overview": true,
            "step_tiles": {
              "registers": 1,
              "isr": 1,
              "ring": 1,
              "receiver": 1,
              "pass": 1
            }
          },
          "interactive": {
            "kind": "uml-class",
            "storage_key": "fc13-a1-context",
            "title": "A1 · UART responsibility boundary",
            "task": {
              "id": "task01",
              "label": "Task01 · UART ISR to frame task"
            },
            "block": {
              "id": "a1",
              "label": "A1 CONTEXT",
              "description": "UART registers, the interrupt path, a bounded handoff and task-only parsing have separate owners."
            },
            "phases": [
              {
                "id": "boundary",
                "label": "PERIPHERAL / ISR / TASK",
                "steps": [
                  {
                    "id": "registers",
                    "number": 1,
                    "label": "UART register bank exposes RX state",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "01",
                    "code_ref": "include/task01_uart.h:27",
                    "description": "UART register bank exposes RX state",
                    "evidence": "status, data and indices"
                  },
                  {
                    "id": "isr",
                    "number": 2,
                    "label": "ISR owns bounded byte transfer",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "02",
                    "code_ref": "src/tasks/task01_uart.c:159",
                    "description": "ISR owns bounded byte transfer",
                    "evidence": "at most ten bytes"
                  },
                  {
                    "id": "ring",
                    "number": 3,
                    "label": "ring connects one producer and one consumer",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "03",
                    "code_ref": "include/task01_uart_model.h:40",
                    "description": "ring connects one producer and one consumer",
                    "evidence": "publish byte before head"
                  },
                  {
                    "id": "receiver",
                    "number": 4,
                    "label": "receiver owns parsing and TX",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "04",
                    "code_ref": "src/tasks/task01_uart.c:207",
                    "description": "receiver owns parsing and TX",
                    "evidence": "no parser in ISR"
                  },
                  {
                    "id": "pass",
                    "number": 5,
                    "label": "runtime validates the boundary",
                    "mode": "RUN",
                    "event_id": "E11",
                    "strategy_ref": "run.identity",
                    "svg_label": "05",
                    "code_ref": "src/tasks/task01_uart.c:346",
                    "snapshot_ref": "task01.pass",
                    "description": "runtime validates the boundary",
                    "evidence": "PASS and stable digest"
                  }
                ]
              }
            ]
          }
        }
      ]
    },
    {
      "title": "A2 — Register, ring and task state",
      "order": 20,
      "content_kind": "prose",
      "asset_page_mode": "one-per-page",
      "page_orientation": "portrait",
      "content_tex": "An eight-slot ring keeps one slot empty. Head belongs to the ISR, tail to the receiver, and dropped counts rejected newest bytes.",
      "assets": [
        {
          "path": "assets/a2-structure.png",
          "html_path": "assets/a2-structure.svg",
          "source_path": "assets/a2-structure.puml",
          "caption": "A2 STRUCTURE — register bank, seven usable ring slots and frame state.",
          "label": "fig:a2-structure",
          "alt": "A2 · bounded UART storage",
          "kind": "diagram",
          "width": 1.0,
          "page_grid": {
            "columns": 1,
            "rows": 1,
            "page_width": 660,
            "page_height": 760,
            "overview": true,
            "step_tiles": {
              "uart": 1,
              "capacity": 1,
              "push": 1,
              "pop": 1,
              "overflow": 1
            }
          },
          "interactive": {
            "kind": "uml-class",
            "storage_key": "fc13-a2-structure",
            "title": "A2 · bounded UART storage",
            "task": {
              "id": "task01",
              "label": "Task01 · UART ISR to frame task"
            },
            "block": {
              "id": "a2",
              "label": "A2 STRUCTURE",
              "description": "The register bank, SPSC ring, frame scratch space and evidence trace have explicit storage and ownership."
            },
            "phases": [
              {
                "id": "storage",
                "label": "BOUNDED STORAGE",
                "steps": [
                  {
                    "id": "uart",
                    "number": 1,
                    "label": "volatile UART fields model device state",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "01",
                    "code_ref": "include/task01_uart.h:27",
                    "description": "volatile UART fields model device state",
                    "evidence": "RX capacity twelve"
                  },
                  {
                    "id": "capacity",
                    "number": 2,
                    "label": "ring has eight slots and seven usable",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "02",
                    "code_ref": "include/task01_uart_model.h:7",
                    "description": "ring has eight slots and seven usable",
                    "evidence": "empty slot disambiguates full"
                  },
                  {
                    "id": "push",
                    "number": 3,
                    "label": "producer publishes data before head",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "03",
                    "code_ref": "include/task01_uart_model.h:43",
                    "description": "producer publishes data before head",
                    "evidence": "single ISR producer"
                  },
                  {
                    "id": "pop",
                    "number": 4,
                    "label": "consumer retires data before tail",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "04",
                    "code_ref": "include/task01_uart_model.h:58",
                    "description": "consumer retires data before tail",
                    "evidence": "single task consumer"
                  },
                  {
                    "id": "overflow",
                    "number": 5,
                    "label": "second IRQ fills seven and drops three",
                    "mode": "RUN",
                    "event_id": "E08",
                    "strategy_ref": "run.overflow",
                    "svg_label": "05",
                    "code_ref": "src/tasks/task01_uart.c:202",
                    "snapshot_ref": "task01.overflow-isr",
                    "description": "second IRQ fills seven and drops three",
                    "evidence": "used=7, dropped=3"
                  }
                ]
              }
            ]
          }
        }
      ]
    },
    {
      "title": "A3 — ISR-to-notification binding",
      "order": 30,
      "content_kind": "prose",
      "asset_page_mode": "one-per-page",
      "page_orientation": "portrait",
      "content_tex": "Only the FromISR notification API appears in the handler; the receiver blocks with the matching task-context take.",
      "assets": [
        {
          "path": "assets/a3-dispatch.png",
          "html_path": "assets/a3-dispatch.svg",
          "source_path": "assets/a3-dispatch.puml",
          "caption": "A3 DISPATCH — MEI, bounded drain, notify and immediate task restore.",
          "label": "fig:a3-dispatch",
          "alt": "A3 · interrupt dispatch",
          "kind": "diagram",
          "width": 1.0,
          "page_grid": {
            "columns": 1,
            "rows": 1,
            "page_width": 660,
            "page_height": 760,
            "overview": true,
            "step_tiles": {
              "vector": 1,
              "entry": 1,
              "budget": 1,
              "notify": 1,
              "yield": 1,
              "receiver-first": 1
            }
          },
          "interactive": {
            "kind": "uml-class",
            "storage_key": "fc13-a3-dispatch",
            "title": "A3 · interrupt dispatch",
            "task": {
              "id": "task01",
              "label": "Task01 · UART ISR to frame task"
            },
            "block": {
              "id": "a3",
              "label": "A3 DISPATCH",
              "description": "The real external interrupt enters the FreeRTOS trap path, clears its source, notifies once and yields once."
            },
            "phases": [
              {
                "id": "dispatch",
                "label": "IRQ / FROMISR / RESTORE",
                "steps": [
                  {
                    "id": "vector",
                    "number": 1,
                    "label": "external vector enters the port trap",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "01",
                    "code_ref": "src/common/hazard3_freertos_traps.S:24",
                    "description": "external vector enters the port trap",
                    "evidence": "full context save"
                  },
                  {
                    "id": "entry",
                    "number": 2,
                    "label": "first IRQ records MEI and ISR stack",
                    "mode": "RUN",
                    "event_id": "E04",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "02",
                    "code_ref": "src/tasks/task01_uart.c:166",
                    "snapshot_ref": "task01.isr-entry",
                    "description": "first IRQ records MEI and ISR stack",
                    "evidence": "mcause is machine external interrupt"
                  },
                  {
                    "id": "budget",
                    "number": 3,
                    "label": "loop obeys a ten-byte budget",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "03",
                    "code_ref": "src/tasks/task01_uart.c:174",
                    "description": "loop obeys a ten-byte budget",
                    "evidence": "bounded ISR work"
                  },
                  {
                    "id": "notify",
                    "number": 4,
                    "label": "one FromISR give merges wake request",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "04",
                    "code_ref": "src/tasks/task01_uart.c:189",
                    "description": "one FromISR give merges wake request",
                    "evidence": "higher-priority task ready"
                  },
                  {
                    "id": "yield",
                    "number": 5,
                    "label": "port performs one requested yield",
                    "mode": "CODE",
                    "strategy_ref": "code.contract",
                    "svg_label": "05",
                    "code_ref": "src/tasks/task01_uart.c:202",
                    "description": "port performs one requested yield",
                    "evidence": "receiver restored first"
                  },
                  {
                    "id": "receiver-first",
                    "number": 6,
                    "label": "receiver completes before stimulus resumes",
                    "mode": "RUN",
                    "event_id": "E06",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "06",
                    "code_ref": "src/tasks/task01_uart.c:256",
                    "snapshot_ref": "task01.frame",
                    "description": "receiver completes before stimulus resumes",
                    "evidence": "stimulus_after_first=0"
                  }
                ]
              }
            ]
          }
        }
      ]
    },
    {
      "title": "A5 — Two-frame replay",
      "order": 50,
      "content_kind": "prose",
      "asset_page_mode": "one-per-page",
      "page_orientation": "portrait",
      "content_tex": "The first interrupt delivers OK plus newline and produces ACK. The second presents ten bytes, accepts seven, drops three and discards the partial frame in task context.",
      "assets": [
        {
          "path": "assets/a5-flow.png",
          "html_path": "assets/a5-flow.svg",
          "source_path": "assets/a5-flow.puml",
          "caption": "A5 FLOW — E01–E11 from configuration to verified PASS.",
          "label": "fig:a5-flow",
          "alt": "A5 · UART pipeline replay",
          "kind": "diagram",
          "width": 1.0,
          "page_grid": {
            "columns": 1,
            "rows": 1,
            "page_width": 660,
            "page_height": 760,
            "overview": true,
            "step_tiles": {
              "config": 1,
              "wait": 1,
              "inject": 1,
              "isr-entry-flow": 1,
              "isr-good": 1,
              "frame": 1,
              "overlong": 1,
              "drop": 1,
              "discard": 1,
              "resume": 1,
              "verified": 1
            }
          },
          "interactive": {
            "kind": "uml-sequence",
            "storage_key": "fc13-a5-flow",
            "title": "A5 · UART pipeline replay",
            "task": {
              "id": "task01",
              "label": "Task01 · UART ISR to frame task"
            },
            "block": {
              "id": "a5",
              "label": "A5 FLOW",
              "description": "Eleven committed events cover one valid frame and one deterministic overflow fixture."
            },
            "phases": [
              {
                "id": "flow",
                "label": "VALID FRAME / OVERFLOW / PASS",
                "steps": [
                  {
                    "id": "config",
                    "number": 1,
                    "label": "configure IRQ and eight-slot ring",
                    "mode": "RUN",
                    "event_id": "E01",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "01",
                    "code_ref": "src/tasks/task01_uart.c:411",
                    "snapshot_ref": "task01.configured",
                    "description": "configure IRQ and eight-slot ring",
                    "evidence": "capacity=8"
                  },
                  {
                    "id": "wait",
                    "number": 2,
                    "label": "receiver reaches notification wait",
                    "mode": "RUN",
                    "event_id": "E02",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "02",
                    "code_ref": "src/tasks/task01_uart.c:219",
                    "snapshot_ref": "task01.receiver-ready",
                    "description": "receiver reaches notification wait",
                    "evidence": "receiver priority 3"
                  },
                  {
                    "id": "inject",
                    "number": 3,
                    "label": "stimulus publishes OK newline",
                    "mode": "RUN",
                    "event_id": "E03",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "03",
                    "code_ref": "src/tasks/task01_uart.c:294",
                    "snapshot_ref": "task01.good-injected",
                    "description": "stimulus publishes OK newline",
                    "evidence": "three RX bytes"
                  },
                  {
                    "id": "isr-entry-flow",
                    "number": 4,
                    "label": "external IRQ enters handler",
                    "mode": "RUN",
                    "event_id": "E04",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "04",
                    "code_ref": "src/tasks/task01_uart.c:166",
                    "snapshot_ref": "task01.isr-entry",
                    "description": "external IRQ enters handler",
                    "evidence": "MEI and ISR SP"
                  },
                  {
                    "id": "isr-good",
                    "number": 5,
                    "label": "ISR queues three and requests wake",
                    "mode": "RUN",
                    "event_id": "E05",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "05",
                    "code_ref": "src/tasks/task01_uart.c:197",
                    "snapshot_ref": "task01.good-isr",
                    "description": "ISR queues three and requests wake",
                    "evidence": "processed=3"
                  },
                  {
                    "id": "frame",
                    "number": 6,
                    "label": "task validates frame and owns ACK",
                    "mode": "RUN",
                    "event_id": "E06",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "06",
                    "code_ref": "src/tasks/task01_uart.c:238",
                    "snapshot_ref": "task01.frame",
                    "description": "task validates frame and owns ACK",
                    "evidence": "good_frames=1"
                  },
                  {
                    "id": "overlong",
                    "number": 7,
                    "label": "stimulus publishes ten X bytes",
                    "mode": "RUN",
                    "event_id": "E07",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "07",
                    "code_ref": "src/tasks/task01_uart.c:306",
                    "snapshot_ref": "task01.overlong-injected",
                    "description": "stimulus publishes ten X bytes",
                    "evidence": "receiver already done"
                  },
                  {
                    "id": "drop",
                    "number": 8,
                    "label": "ISR accepts seven and drops three",
                    "mode": "RUN",
                    "event_id": "E08",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "08",
                    "code_ref": "src/tasks/task01_uart.c:202",
                    "snapshot_ref": "task01.overflow-isr",
                    "description": "ISR accepts seven and drops three",
                    "evidence": "drop-newest"
                  },
                  {
                    "id": "discard",
                    "number": 9,
                    "label": "task discards partial overflow frame",
                    "mode": "RUN",
                    "event_id": "E09",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "09",
                    "code_ref": "src/tasks/task01_uart.c:249",
                    "snapshot_ref": "task01.overflow-task",
                    "description": "task discards partial overflow frame",
                    "evidence": "overflow_frames=1"
                  },
                  {
                    "id": "resume",
                    "number": 10,
                    "label": "stimulus resumes after receiver",
                    "mode": "RUN",
                    "event_id": "E10",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "10",
                    "code_ref": "src/tasks/task01_uart.c:315",
                    "snapshot_ref": "task01.stimulus-resumed",
                    "description": "stimulus resumes after receiver",
                    "evidence": "second_done=1"
                  },
                  {
                    "id": "verified",
                    "number": 11,
                    "label": "verifier commits deterministic PASS",
                    "mode": "RUN",
                    "event_id": "E11",
                    "strategy_ref": "run.identity",
                    "svg_label": "11",
                    "code_ref": "src/tasks/task01_uart.c:376",
                    "snapshot_ref": "task01.pass",
                    "description": "verifier commits deterministic PASS",
                    "evidence": "digest 6089cfff"
                  }
                ]
              }
            ]
          }
        }
      ]
    },
    {
      "title": "A6 — Ring and receiver states",
      "order": 60,
      "content_kind": "prose",
      "asset_page_mode": "one-per-page",
      "page_orientation": "portrait",
      "content_tex": "Notification is a wake signal, not the byte container. The ring carries data; the receiver drains all published bytes after each wake.",
      "assets": [
        {
          "path": "assets/a6-state.png",
          "html_path": "assets/a6-state.svg",
          "source_path": "assets/a6-state.puml",
          "caption": "A6 STATE — empty, filling, notified, draining and overflow recovery.",
          "label": "fig:a6-state",
          "alt": "A6 · ring and task state",
          "kind": "diagram",
          "width": 1.0,
          "page_grid": {
            "columns": 1,
            "rows": 1,
            "page_width": 660,
            "page_height": 760,
            "overview": true,
            "step_tiles": {
              "empty": 1,
              "filled": 1,
              "drained": 1,
              "full": 1,
              "recovered": 1
            }
          },
          "interactive": {
            "kind": "uml-class",
            "storage_key": "fc13-a6-state",
            "title": "A6 · ring and task state",
            "task": {
              "id": "task01",
              "label": "Task01 · UART ISR to frame task"
            },
            "block": {
              "id": "a6",
              "label": "A6 STATE",
              "description": "Ring occupancy and receiver state change independently but obey one publication contract."
            },
            "phases": [
              {
                "id": "state",
                "label": "RING / NOTIFICATION / FRAME",
                "steps": [
                  {
                    "id": "empty",
                    "number": 1,
                    "label": "empty ring and blocked receiver",
                    "mode": "RUN",
                    "event_id": "E03",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "01",
                    "code_ref": "src/tasks/task01_uart.c:297",
                    "snapshot_ref": "task01.good-injected",
                    "description": "empty ring and blocked receiver",
                    "evidence": "head=tail before IRQ"
                  },
                  {
                    "id": "filled",
                    "number": 2,
                    "label": "three bytes published before notify",
                    "mode": "RUN",
                    "event_id": "E05",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "02",
                    "code_ref": "src/tasks/task01_uart.c:174",
                    "snapshot_ref": "task01.good-isr",
                    "description": "three bytes published before notify",
                    "evidence": "used=3"
                  },
                  {
                    "id": "drained",
                    "number": 3,
                    "label": "receiver drains and returns to wait",
                    "mode": "RUN",
                    "event_id": "E06",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "03",
                    "code_ref": "src/tasks/task01_uart.c:229",
                    "snapshot_ref": "task01.frame",
                    "description": "receiver drains and returns to wait",
                    "evidence": "head=tail"
                  },
                  {
                    "id": "full",
                    "number": 4,
                    "label": "second IRQ reaches seven usable slots",
                    "mode": "RUN",
                    "event_id": "E08",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "04",
                    "code_ref": "include/task01_uart_model.h:47",
                    "snapshot_ref": "task01.overflow-isr",
                    "description": "second IRQ reaches seven usable slots",
                    "evidence": "dropped=3"
                  },
                  {
                    "id": "recovered",
                    "number": 5,
                    "label": "receiver resets partial frame",
                    "mode": "RUN",
                    "event_id": "E09",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "05",
                    "code_ref": "src/tasks/task01_uart.c:249",
                    "snapshot_ref": "task01.overflow-task",
                    "description": "receiver resets partial frame",
                    "evidence": "frame length zero"
                  }
                ]
              }
            ]
          }
        }
      ]
    },
    {
      "title": "A7 — Runtime and artifact proof",
      "order": 70,
      "content_kind": "prose",
      "asset_page_mode": "one-per-page",
      "page_orientation": "portrait",
      "content_tex": "Three clean simulator processes must produce the same terminal digest. ABI checks reject C++ and require the trap, notification and task boundaries.",
      "assets": [
        {
          "path": "assets/a7-runtime.png",
          "html_path": "assets/a7-runtime.svg",
          "source_path": "assets/a7-runtime.puml",
          "caption": "A7 RUNTIME — cause, stacks, indices, symbols and deterministic identity.",
          "label": "fig:a7-runtime",
          "alt": "A7 · runtime proof",
          "kind": "diagram",
          "width": 1.0,
          "page_grid": {
            "columns": 1,
            "rows": 1,
            "page_width": 660,
            "page_height": 760,
            "overview": true,
            "step_tiles": {
              "cause": 1,
              "indices": 1,
              "stacks": 1,
              "abi": 1,
              "determinism": 1
            }
          },
          "interactive": {
            "kind": "uml-class",
            "storage_key": "fc13-a7-runtime",
            "title": "A7 · runtime proof",
            "task": {
              "id": "task01",
              "label": "Task01 · UART ISR to frame task"
            },
            "block": {
              "id": "a7",
              "label": "A7 RUNTIME",
              "description": "The proof combines register values, ring indices, three stack contexts, event order and exact C artifact identity."
            },
            "phases": [
              {
                "id": "runtime",
                "label": "RUNTIME EVIDENCE",
                "steps": [
                  {
                    "id": "cause",
                    "number": 1,
                    "label": "mcause proves a real external IRQ",
                    "mode": "RUN",
                    "event_id": "E04",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "01",
                    "code_ref": "src/tasks/task01_uart.c:167",
                    "snapshot_ref": "task01.isr-entry",
                    "description": "mcause proves a real external IRQ",
                    "evidence": "0x8000000b"
                  },
                  {
                    "id": "indices",
                    "number": 2,
                    "label": "head and tail stay inside capacity",
                    "mode": "RUN",
                    "event_id": "E09",
                    "strategy_ref": "run.pipeline",
                    "svg_label": "02",
                    "code_ref": "src/tasks/task01_uart.c:266",
                    "snapshot_ref": "task01.overflow-task",
                    "description": "head and tail stay inside capacity",
                    "evidence": "ring empty after drain"
                  },
                  {
                    "id": "stacks",
                    "number": 3,
                    "label": "ISR, receiver and stimulus stacks differ",
                    "mode": "RUN",
                    "event_id": "E11",
                    "strategy_ref": "run.identity",
                    "svg_label": "03",
                    "code_ref": "src/tasks/task01_uart.c:373",
                    "snapshot_ref": "task01.pass",
                    "description": "ISR, receiver and stimulus stacks differ",
                    "evidence": "three SP values"
                  },
                  {
                    "id": "abi",
                    "number": 4,
                    "label": "ELF exposes C and FromISR boundaries",
                    "mode": "CODE",
                    "strategy_ref": "code.identity",
                    "svg_label": "04",
                    "code_ref": "scripts/check_abi.sh:18",
                    "description": "ELF exposes C and FromISR boundaries",
                    "evidence": "no C++ or unwind"
                  },
                  {
                    "id": "determinism",
                    "number": 5,
                    "label": "three clean runs agree",
                    "mode": "RUN",
                    "event_id": "E11",
                    "strategy_ref": "run.identity",
                    "svg_label": "05",
                    "code_ref": "scripts/check_determinism.sh:14",
                    "snapshot_ref": "task01.pass",
                    "description": "three clean runs agree",
                    "evidence": "identical digest"
                  }
                ]
              }
            ]
          }
        }
      ]
    },
    {
      "title": "Task01 — UART ISR to frame task",
      "order": 90,
      "content_kind": "tasks",
      "task_refs": [
        "task01"
      ]
    }
  ],
  "tasks": {
    "task01": {
      "title": "Build and prove a bounded UART RX pipeline",
      "uuid": "6a838fd1-ab1b-52b6-baaf-659120a4d60a",
      "prompt_tex": "Odtwórz E01--E11. Udowodnij, że ISR tylko przenosi bajty i budzi zadanie, a parser oraz TX działają wyłącznie w kontekście zadania.",
      "criterion": "PASS; two real IRQs; ISR budget <= 10; valid ACK; seven accepted and three dropped on overflow; no index or TX ownership violation; deterministic digest.",
      "conclusion_tex": "Notyfikacja przenosi informację o pracy, nie bajty. Dane mają osobny ograniczony ring; kolejność publikacji, budżet ISR i jawna polityka przepełnienia są częścią kontraktu.",
      "flow": [
        {
          "kind": "block",
          "id": "contract",
          "title": "A — kontrakt",
          "content_tex": "Rozdziel właścicieli rejestrów, indeksów, parsera i TX.",
          "steps": [
            {
              "id": "owners",
              "title": "Zapisz tabelę własności.",
              "content_tex": "ISR zapisuje head; zadanie zapisuje tail i stan ramki."
            },
            {
              "id": "predict",
              "title": "Przewidź dwa przebiegi.",
              "content_tex": "Wyznacz zajętość ringa dla trzech i dziesięciu bajtów."
            }
          ]
        },
        {
          "kind": "block",
          "id": "replay",
          "title": "B — replay",
          "content_tex": "Powiąż każdy RUN z jednym zatwierdzonym eventem.",
          "steps": [
            {
              "id": "valid",
              "title": "Sprawdź E03--E06.",
              "content_tex": "Trzy bajty, wake request, ACK i natychmiastowy receiver."
            },
            {
              "id": "overflow",
              "title": "Sprawdź E07--E10.",
              "content_tex": "Siedem zaakceptowanych, trzy odrzucone i reset ramki."
            },
            {
              "id": "identity",
              "title": "Sprawdź E11.",
              "content_tex": "ABI, trzy stosy, kolejność i digest."
            }
          ]
        },
        {
          "kind": "exercise",
          "id": "policy",
          "title": "Ćwiczenie — polityka przepełnienia",
          "prompt_tex": "Zmień wyłącznie politykę z drop-newest na drop-oldest. Zapisz nowy kontrakt indeksów i przewidź, które siedem z dziesięciu bajtów odczyta zadanie.",
          "evidence_tex": "Tabela bajtów wejściowych, head/tail przed i po IRQ, drop counter oraz ślad zadania.",
          "criterion": "Uczeń zachowuje bounded ISR, nie publikuje indeksu przed bajtem i potrafi wskazać utracone dane.",
          "based_on": [
            "contract",
            "replay"
          ]
        }
      ],
      "educational_requirement_refs": [
        "FC13.WE01"
      ],
      "learning_effect_refs": [
        "FC13.EN01",
        "FC13.EK01"
      ],
      "assessment_criterion_ref": "FC13.KW01"
    }
  },
  "tasks_order": [
    "task01"
  ]
}