132
RS-232C interface
(continued)
Software specifications (protocol)
1.
Communication parameters
The underlining (__) denotes the factory setting mode.
The settings can be changed in the following Setup Menu.
2.Send format
[controller (PC)
>
VTR]
The following responses are for command instructions.
Multiple responses may be made if necessary.
_
Data format
20H<XX<7FH
(XX=ASCII code: symbols, numbers, upper-case let-
ters)
[command]:
This is the command identifier (3 bytes).
A 3-byte identifier (ASCII code: symbols, numbers,
upper-case letters) is sent as the command.
[:]:
The colon is the code serving as a delimiter between
the command and data.
[data]:
Data (ASCII code: symbols, numbers, upper-case let-
ters) can be added in the number of bytes required.
_
Outline of procedure for sending data 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 command 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 133.)
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.
Communicati
on system
Asynchronous, full duplex
Transfer rate
300, 600, 1200, 2400, 4800 or 9600 bps
Bit length
7 bits or 8 bits
Stop bit
1 bit or 2 bits
Parity bit
None, odd or even
ACK code
Returned or not returned
<Note>
ACK is the code which is returned from the VTR
to the controller when data has been successfully
sent from the controller.
Communicati
on parameter
Setup menu item
Transfer rate
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
[STX]
[command]
[:]
[data]
[ETX]
02h
XX XX XX
3Ah
XX.....XX
03h
