Appendix: Serial programming interface

Introduction

This section describes the remote control protocol for controlling the AVR350 via the RS232 interface.

Conventions

<All values in this section are hexadecimal values, unless otherwise specified.

Data transfer format

<Transfer rate: 38,400bps.

<1 start bit, 8 data bits, 1 stop bit, no parity, no flow control.

Command and response formats

Communication between the remote controller (RC) and the AVR350 takes the form of sequences of ASCII characters, with all commands and responses having the same basic format. The AVR350 shall always respond to a received command, but may also send messages at other times (i.e., full-duplex communication).

Each transmission by the RC is seven bytes long with the following format: <STR> <CC> <P1> <P2> <ETR>

<

<

<

<

STR (Start transmission): 0x50, 0x43, 0x5F (‘PC_’)

CC (Command code): the code for the command

Px (Parameter code): the parameters for the command

ETR (End transmission): 0xd

Each response by the AVR350 is eight bytes long with the following format: <STR> <RC> <AC> <P1> <P2> <ETR>

<

<

<

<

<

STR (Start transmission): 0x41, 0x56, 0x5f (‘AV_’)

RC (Reply code): = command code

AC (Answer code): answer code (see below)

Px (Parameter code): the parameters for the reponse

ETR (End transmission): 0xd

The AVR350 responds to each command from the RC within three seconds. The RC may send further commands before a previous command response has been received.

Answer codes

The following answer codes are defined:

<Command OK – ‘P’ (0x50): The command has been accepted and processed completely.

<Command Error – ‘R’ (0x52): An error occurred relating to the command received. This may be either an invalid command (at this time), or a command formatting error.

State changes as a result of other inputs

It is possible that the state of the AVR350 may be changed as a result of user input via the front panel buttons or via the IR remote control. Changes resulting from these inputs is relayed to the RC using the appropriate message type.

For example, if the user changed the front panel display brightness using the DISPLAY button on the front panel, a display message (defined below) would be sent to the RC. A similar action would be taken for all other state changes (including decode mode changes).

Example command and response sequence

As an example, the command to be sent to bring the main zone out of stand-by (defined below) is as follows:

STR CC P1 P2 ETR

PC_ * 1 1 (0xd)

Assuming that the command was accepted by the AVR350, the AVR350 shall respond to this command with the following sequence:

STR RC AC P1 P2 ETR

AV_ * P 1 1 (0xd)

AVR350

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Arcam AVR350 manual Appendix Serial programming interface, Command and response formats

AVR350 specifications

The Arcam AVR350 is a high-performance AV receiver that epitomizes the blend of cutting-edge technology and sophisticated design. Known for its exceptional sound quality and advanced features, it caters to audiophiles and home theater enthusiasts alike. The AVR350 stands out with its robust build quality and user-friendly interface, making it an attractive option for those looking to enhance their home entertainment experience.

One of the key features of the Arcam AVR350 is its 7.1-channel amplification, delivering a powerful audio output of 90 watts per channel. This ensures that every sound in your favorite movies, music, or games is reproduced with clarity and depth. The receiver is equipped with advanced Dolby Digital and DTS decoding technologies, which allow it to support high-definition audio formats. This means users can enjoy a truly immersive surround sound experience, whether it’s the booming effects of an action movie or the delicate nuances of a classical performance.

Another standout characteristic of the AVR350 is its digital signal processing. Incorporating sophisticated algorithms, it optimizes audio performance for different environments, ensuring that listeners achieve the best sound quality no matter the size or shape of the room. The inclusion of Arcam's proprietary room EQ technology further enhances the listening experience by adjusting the sound to compensate for the room acoustics, providing a balanced audio output tailored to individual environments.

Connectivity options are comprehensive, with multiple HDMI inputs and outputs supporting high-definition video formats. The AVR350 also supports a variety of other audio-video inputs, including component and composite video connections, as well as analog audio inputs. This versatility makes it easy to integrate with a range of devices, including Blu-ray players, gaming consoles, and streaming devices.

For users keen on multi-room audio solutions, the AVR350 offers the capability to distribute audio to several zones, allowing you to enjoy different music or media in various parts of the home simultaneously. The intuitive on-screen menu simplifies setup and operation, ensuring that users can easily configure their systems according to their preferences.

In summary, the Arcam AVR350 is a well-rounded AV receiver that combines impressive audio performance, advanced decoding technologies, and flexible connectivity options. Its focus on high-quality sound and user convenience makes it an ideal choice for those looking to elevate their home entertainment systems. With the AVR350, enthusiasts can expect a level of audio fidelity that truly transforms the way they experience sound.