AVC-LAN

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Revision as of 16:56, 30 November 2009 by Prpplague (Talk | contribs) (Protocol)

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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:

AVC-LAN consist of audio visual systems such as the multi-display, navigation ECU, radio and
player, stereo component amplifier and gateway ECU. Gateway ECU has communication
circuit to correspond with different types of communication data. Different types of
communication data can be shared among communication parts after it goes through gateway
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

Logic Probe Capture of AVC-LAN Message

Hardware

Specific

  • Renesas HA12240 Differential Transceiver
  • 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