LIN Description Files (LDF)

LIN_description_file;
LIN_protocol_version = "2.2";
LIN_language_version = "2.2";
LIN_speed = 19.2 kbps;

Nodes {
  Master: BCM, 5 ms, 0.5 ms;  /* timebase=5ms, jitter=0.5ms */
  Slaves: WindowMotor_FL, WindowMotor_FR, Mirror_L;
}

Signals {
  WindowPos_FL: 8, 0x00, WindowMotor_FL, BCM;  /* name: bits, init, publisher, subscriber */
  WindowCmd_FL: 8, 0x00, BCM, WindowMotor_FL;  /* master commands slave */
  MirrorH_L:    8, 0x80, Mirror_L, BCM;
  MirrorV_L:    8, 0x80, Mirror_L, BCM;
}

Frames {
  WindowStatus_FL: 0x01, WindowMotor_FL, 2 {  /* ID, publisher, DLC */
    WindowPos_FL, 0;    /* signal, start bit */
    response_error, 8;  /* LIN slave status bit */
  }
  MirrorStatus_L: 0x03, Mirror_L, 2 {
    MirrorH_L, 0;
    MirrorV_L, 8;
  }
  WindowCommand_FL: 0x10, BCM, 2 {  /* BCM publishes command */
    WindowCmd_FL, 0;
  }
}

Schedule_tables {
  Normal {
    WindowStatus_FL    delay 10 ms;
    MirrorStatus_L     delay 10 ms;
    WindowCommand_FL   delay 20 ms;
  }
}

Signal_encoding_types {
  /* Physical value: WindowPos = raw × 0.39 + 0 (0-100%) */
  WindowPos_Encoding {
    physical_value, 0, 255, 0.39, 0, "pct";
  }

  /* Logical (enum) values for window command */
  WindowCmd_Encoding {
    logical_value, 0, "STOP";
    logical_value, 1, "UP";
    logical_value, 2, "DOWN";
    logical_value, 3, "ANTI_PINCH";
  }

  /* Mirror position: 0-255 = centre ± 90° */
  MirrorPos_Encoding {
    physical_value, 0, 255, 0.706, -90, "deg";
  }
}

Signal_representation {
  WindowPos_Encoding: WindowPos_FL;
  WindowCmd_Encoding: WindowCmd_FL;
  MirrorPos_Encoding: MirrorH_L, MirrorV_L;
}

#!/bin/bash
# LDF validation pipeline before hardware bring-up

# 1. Vector LINdb++ headless validation
lindb_cli.exe -validate body_lin.ldf     -check-timing     -check-signal-encoding     -output ldf_validation_report.html

# 2. Schedule table timing check (Python)
python3 - <<'EOF'
from ldf_parser import LDFFile
import math

ldf = LDFFile("body_lin.ldf")
baud = ldf.speed  # 19200

for sched_name, schedule in ldf.schedules.items():
    cycle_time = sum(slot.delay_ms for slot in schedule.slots)
    print(f"Schedule '{sched_name}': cycle={cycle_time:.1f} ms")
    for slot in schedule.slots:
        frame = ldf.frames[slot.frame_name]
        t_header = 34 / baud * 1000  # ms
        t_response = (frame.dlc + 1) * 10 / baud * 1000
        t_min = t_header + t_response + 0.5  # 0.5ms response space
        if slot.delay_ms < t_min:
            print(f"  ERROR: {slot.frame_name} slot={slot.delay_ms:.1f}ms < min={t_min:.2f}ms")
        else:
            print(f"  OK: {slot.frame_name} slot={slot.delay_ms:.1f}ms (min={t_min:.2f}ms)")
EOF