From: eLinux.org

AVC-LAN

Contents

Introduction

The AVC-LAN is part of the Body Electrical System Control and manages
all audio and video related functions. The audio bus is described in
Toyota’s own words as follows:

  1. AVC-LAN consist of audio visual systems such as the multi-display, navigation ECU, radio and
  2. player, stereo component amplifier and gateway ECU. Gateway ECU has communication
  3. circuit to correspond with different types of communication data. Different types of
  4. communication data can be shared among communication parts after it goes through gateway
  5. ECU (System Circuits: AVC-LAN Bus, Prius Wiring Diagram 80).

The system itself can be considered a subset of the IEBus Standard,
which was delevoped by NEC electronics for automotive use. It is
slightly faster than the BEAN Bus and has more
data per command, but is still much slower than CAN
Bus
, since realtime speeds are not required.

Connections

Iebus-connections.gif

Waveform

Iebus-waveform.jpg

  • Prep 7uS
  • Sync 20uS
  • Data 13uS

Protocol

Iebus-message.jpg

Avc-lan-message.jpg

This is an AVC-LAN message captured using a logic probe.

Hardware

Specific

  • Renesas HA12240
    Differential Transceiver
    • A2240 Package Marking
    • CA0008 Package Marking
    • CA0013 Package Marking
  • NEC uPD6708 IEBus (Inter
    Equipment Bus) Protocol Controller
  • NEC uPD72042 IEBus
    (Inter Equipment Bus) Protocol Controller

General Purpose

  • LM239 comparator (can be used for receiver)
  • PCA82C250 CAN Bus (can be used for driver)
  • MCP2551 CAN Bus (can be used for driver)
  • RS-485 Differential Transceiver ( can be used for both receiver and
    driver)
    • SN65HVD11 +3.3V
    • SN75HVD11 +5v

Hacks

Documentation Credit

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