![](/images/new-backgrounds/1280759/28075963x1.webp)
RS-232C Interface
2. Software specifications
1) External interface specifications
Communication system | Asynchronous, full duplex |
Baud rate | 1200/2400/4800/9600/19200 |
Bit length | 8 bit/7 bit |
Stop bit | 1 bit/2 bit |
Parity | NONE/ODD/EVEN |
The factory settings are 9600 bps, 8 bits, 1 stop bit, and none for the parity.
2) Sending format (from personal computer to VTR)
Data format
[STX] [discrimination] [:] [data] [ETX]
02H | XX XX XX | 3AH XX XX 03H |
| 20H<XX<7FH | (XX = hexadecimal character code) |
discrimination | : This is the command identifier (3 bytes). | |
|
| : This code serves as the delimiter between a command and data. |
data | : Data codes are added when necessary. |
1. A send command must always start with STX (character code 02H).
The ‘discrimination’which follows next is the command identifier. If necessary, data is added after the colon (" : ").
At the very end comes ETX (character code 03H).
2.When STX is
3)Receiving format (from VTR to personal computer)
The VTR responds to a send command with data in the following format.
1.First, the VTR returns the data which acknowledges whether the command from the computer was received properly.
1) The VTR returns the ACK data if communication was
[ACK]
06H
2)It returns data starting with NAK (negative acknowledge; character code 15H) if an error occurred in communication.
[NAK]
15H
32