PDU Refactor

.vscode/launch.json

@@ -239,4 +239,4 @@
             }
         }
     ]
-}
+}

can_library/configs/nodes/PDU.json

@@ -32,7 +32,7 @@
                             "unit": "mV"
                         }
                     ],
-                    "msg_period": 500,
+                    "msg_period": 100,
                     "msg_priority": 4
                 },
                 {
@@ -52,7 +52,7 @@
                             "unit": "mA"
                         }
                     ],
-                    "msg_period": 500,
+                    "msg_period": 100,
                     "msg_priority": 4
                 },
                 {
@@ -82,7 +82,7 @@
                             "length": 12
                         }
                     ],
-                    "msg_period": 500,
+                    "msg_period": 100,
                     "msg_priority": 4
                 },
                 {
@@ -102,7 +102,7 @@
                             "length": 12
                         }
                     ],
-                    "msg_period": 500,
+                    "msg_period": 100,
                     "msg_priority": 4
                 },
                 {
@@ -140,7 +140,7 @@
                             "length": 12
                         }
                     ],
-                    "msg_period": 500,
+                    "msg_period": 100,
                     "msg_priority": 4
                 },
                 {
@@ -197,7 +197,7 @@
                             "unit": "LPM"
                         }
                     ],
-                    "msg_period": 200,
+                    "msg_period": 100,
                     "msg_priority": 5
                 },
                 {
@@ -211,7 +211,7 @@
                             "unit": "C"
                         }
                     ],
-                    "msg_period": 500,
+                    "msg_period": 100,
                     "msg_priority": 5
                 },
                 {

source/pdu/CMakeLists.txt

@@ -4,4 +4,4 @@ add_firmware_component(
     NAME pdu
     LINKER_SCRIPT "STM32F407VGTx_FLASH"
     LIBS "can_node_PDU;CMSIS_F407;PHAL_F407;FREERTOS_F407;BANGBANG;HEARTBEAT;WATCHDOG"
-)
+)

source/pdu/README.md

@@ -1,2 +1,85 @@
-## PDU
-PDU is responsible for controlling and monitoring critical power rails and cooling loops.
+# PDU Firmware
+
+PDU controls and monitors low-voltage power rails and cooling hardware for the car.
+
+## Responsibilities
+
+- Control switchable rails (GPIO outputs).
+- Sample ADC channels for rail voltage/current telemetry.
+- Scan rail nFAULT lines and report/latch faults.
+- Control fan/pump/hxfan outputs and fan PWM duty cycles.
+- Publish PDU telemetry and coolant output status over CAN.
+
+## Module Layout
+
+- `main.c`
+  - Board init, peripheral init, task definitions, task startup order.
+  - No business logic beyond orchestration.
+
+- `state.h/.c`
+  - Shared runtime state (`g_pdu_state`) for all PDU logic.
+
+- `switches.h/.c`
+  - Switch command/read API.
+  - ADC and mux measurement pipeline.
+  - Rail current/voltage conversions.
+  - Default-rail enable sequence.
+
+- `faults.h/.c`
+  - Table-driven nFAULT polling.
+  - One-fault-slot-per-cycle update cadence.
+  - Rail fault LED behavior.
+
+- `cooling.h/.c`
+  - Cooling policy computation.
+  - Cooling actuation (switches + fan PWM).
+  - Cooling CAN output publication.
+
+- `cooling_bangbang.h/.c`
+  - Optional bang-bang policy backend.
+  - Compiled in but disabled by default.
+
+- `telemetry.h/.c`
+  - Power/thermal telemetry CAN publication.
+  - Flowrate telemetry CAN publication.
+
+- Hardware adapter modules (kept separate):
+  - `led/`
+  - `fan_control/`
+  - `flow_rate/`
+
+## Runtime State (`g_pdu_state`)
+
+The shared state contains:
+
+- `rail_voltage_mv` for 24V/5V/3V3 measurements.
+- `switch_current_ma[]` for sensed currents (switch and rail channels).
+- `mux_adc_counts[]` and `next_mux_channel` for mux-sampled inputs.
+- `next_rail_fault_index` for staggered rail fault scanning.
+- `cooling_command` for requested/applied cooling outputs.
+
+## Task Model
+
+Defined in `main.c`:
+
+- `CAN_rx_update` (0 ms)
+- `CAN_tx_update` (5 ms)
+- `switches_periodic` (15 ms)
+- `cooling_periodic` (100 ms)
+- `faults_periodic` (100 ms)
+- `fault_library_periodic` (100 ms)
+- `telemetry_flow_periodic` (200 ms)
+- `LED_periodic` (500 ms)
+- `telemetry_power_periodic` (500 ms)
+- Heartbeat task (LED sweep callback)
+
+## Cooling Backend: Bang-Bang (Disabled by Default)
+
+The bang-bang backend is present for future policy work, but disabled to preserve current behavior.
+
+- Toggle: `COOLING_ENABLE_BANGBANG` in `cooling_bangbang.h`
+  - `0` (default): backend is a no-op.
+  - `1`: motor temp based bang-bang updates are applied.
+
+Current non-bangbang behavior remains the active policy path.
+