RS-232 Implementation Overview

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RS-232 Specification

TASCAM's 322 cassette deck has a standard RS- 232C port, capable of receiving commands and sending status information. Commands are included for transport functions, including CPS (Compumatic Program Search), Counter Reset, and Sync Reverse settings. Tally information will include deck status, timer information and record prohibit status.

• Individual Control Over Each Deck

RS-232 Pin Assignment & Protocol Specification:

• Extensive Transport Control Command Set

(Includes CPS, RTZ, Sync Reverse and Dubbing)

• Transport Status Tallies

• Tape Counter Readout Information (MM:SS)

• Tape Counter Reset Command

Connector:	DB9
Pin 2:	Rx Data
Pin 3:	Tx Data
Pin 5:	Ground
	Rx Data

Data Transmission Speed: 9600 bps

Command Spacing:		>20msec
Character Length:		8 bit
Parity Bit:		None
Stop Bit:		1 bit
2	Tx Data
2

• Tape Status (Record Prohibit/Enable)

• Empty Deck Indication

COMMAND STRUCTURE & BEHAVIOR

Basic Transport Commands:

eli

0Ah

30h

31h

30h

31h

30h

31h

0Dh

PLAY, DECK 1, SIDE A

Tx Data			Rx Data
	3
Ground			Ground


	5


322 RS-232 Port		External Unit

Status Request Commands:

and

imit

0Ah

30h

35h

30h

31h

00h

SENSE MECHANISM STATUS, DECK 1

Preamble - All command strings for the 322 begin with an identifying phrase of "Line Feed" (0Ah) and a "0" (30h).

Command - The command follows the preamble directly. (For a complete list of all the commands, see Transport Commands on the next page.)

Deck - This determines whether the command is targeted at Deck 1 (30h 31h) or Deck 2 (30h 32h).

Direction - For commands which have directionality to it, this determines whether the forward or reverse direction is desired. Forward direction (30h 31h) and reverse direction (30h 32h) are used for commands with direction. Transport commands without direction use a "no direction" (30h 30h) place holder.

Delimiter - All command strings for the 322 end with "Carriage Return" (0Dh) as the delimiter.

Status request commands will follow the same structure as basic transport commands, except a direction is not included in the command. (That information will be given in the reply.)

The 322 does not automatically generate status commands when mechanisms change, so the controller will need to scan the 322 at some rate.

When setting a scanning cycle, it is important to recognize that the 322 requires 20 milliseconds between commands. Since there are 3 types of information per deck (time, record prohibit, and mechanism status), it is easily possible to scan each status every half second, and still only be sending messages to the 322 every 83 milliseconds.

TASCAM USA has tested the 322, scanning each status type every half second, and the 322 performed flawlessly.

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All features and specifications are subject to change without notice. Contact your local TASCAM representative for the latest information.	322_RS-232_TECHDOC.pdf
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RS-232 specifications

The Tascam RS-232 is an essential interface for seamless communication between audio equipment and computers, specifically designed for enhancing the control and automation of professional audio systems. Known for its reliability and versatility, the RS-232 interface utilizes the standard serial communication protocol, allowing for efficient data transfer and enabling the integration of multiple devices within a studio environment.

One of the main features of the Tascam RS-232 is its ability to facilitate remote control of audio devices, such as mixers and digital recorders, via various control software. This capability means that operators can manage audio setups from a distance, enhancing workflow and efficiency during recording sessions. Additionally, the RS-232 port supports bi-directional communication, allowing devices to send and receive data, which is crucial for ensuring synchronization between different components in a typical audio rig.

The technology behind RS-232 communication includes its use of a single-ended signaling method, which employs voltage levels to represent binary data. This characteristic results in a straightforward setup, as fewer components are needed to establish connections. Despite technological advancements, the RS-232 interface remains a prevalent choice in the audio industry due to its ruggedness and ability to function effectively over long distances, typically up to 50 feet or more, depending on the cable quality and environment.

Another noteworthy aspect of the Tascam RS-232 is its low signal degradation, which preserves audio integrity during transmission. This is vital in professional audio applications where fidelity is paramount. The interface is also characterized by its simple configuration, requiring minimal setup and enabling users to quickly integrate it into their systems.

Furthermore, the Tascam RS-232 supports a variety of baud rates, allowing users to customize the speed of data transmission based on their specific requirements. This flexibility ensures that the interface can accommodate various audio setups, from small home studios to large professional environments.

In summary, the Tascam RS-232 serves as a vital tool for anyone looking to streamline their audio production process. Its robustness, ease of use, and efficient communication features combined with the ability to control multiple devices remotely make it an indispensable asset for both amateur and professional audio engineers alike. As technology continues to evolve, the enduring legacy of the RS-232 interface underscores its significance in the world of audio production.

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