• [ : ]:
• [data]:

RS-232C interface

3. Software specifications

Protocol

1) Communication parameters

Communication system

Asynchronous, full duplex

 

 

Communication speed

300/600/1200/2400/4800/9600

 

 

Bit length

7 bit/8 bit

 

 

Stop bit

1 bit/2 bit

 

 

Parity bit

NONE/ODD/EVEN

 

 

ACK code

ACK code returned/ACK code not returned

 

<Note>

 

The ACK code is what is returned from the VTR to the controller when data has

 

been successfully sent from the controller.

 

 

The underlining indicates the factory settings.

Any changes to the settings can be made using the setup menu items listed below.

Communication parameter

Setup menu item

 

 

Communication speed

No. 205 BAUD RATE

 

 

 

Bit length

No. 206

DATA LENGTH

 

 

 

Stop bit

No. 207

STOP BIT

 

 

 

Parity bit

No. 208

PARITY

 

 

ACK code

No. 209 RETURN ACK

 

 

 

2) Send format [controller (PC) →

VTR]

 

■ Data format

 

 

[STX] [command] [:] [data] [ETX]

← (ASCII code: symbols, numbers upper-case letters)

02h XX XX XX 3Ah XX-XX

03h

20h<XX<7Fh

•[command]: Command identifier; a 3-byte identifier (ASCII code: symbols, numbers, upper-case letters) is sent as the

command.

This code serves as a delimiter between the command and data.

Data (ASCII code: symbols, numbers, upper-case letters) can be added in the number of bytes required.

■Outline of send procedure from controller

1.The send command starts with STX (start of text = 02h). The command is then identified by COMMAND which follows and the data is added as required.

The format ends with ETX (end of text = 03h).

2.When a different command is to be sent, a response is awaited from the VTR, and then the command is sent. (See page 92.)

3.If STX is sent again before ETX is sent, the receive data buffer inside the VTR is cleared. A command error is returned to the controller, and the data is newly processed with STX which was received again at the head.

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