RS-232C interface

Software specifications (Protocol)

1.Communication parameters

Communication

Asynchronous, full duplex

system

 

 

 

Communication

300/600/1200/2400/4800/9600

speed

 

 

 

Bit length

7bit/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

Setup menu item

parameter

 

 

 

 

 

Communication

No.205 BAUD RATE

speed

 

 

 

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) 5 VTR]

$ Data format

[STX]

[command]

[:]

[data]

[ETX]

02h

XX XX XX

3Ah

XX

.....

XX

03h

 

20H<XX<7FH

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

[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] :

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

$ Outline of send procedure from controller

1The 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).

2When a different command is to be sent, a response is awaited from the VTR, and then the command is sent. (See page 72.)

3If 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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