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Rs-232c interface, Electrical specifications – JVC VR-509E User Manual

Page 116

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RS-232C Interface

116

1. D-Sub 9-pin Connector Specifications

2. Data Format

Mode:

Asynchronous

Character Length: 8bit

Parity Check:

None

Stop Bit:

1bit

Data Speed:

9600bps

3. Command Format and ACK/NAK

Control: No control sequence

• The ACK (NAK) response will be returned within 200ms for a 1byte transmission command from the CPU.

• The NAK response is returned only when a non-defined command is received (however, NAK is returned for certain

commands depending on the status.)

• The parameters for data that have elapsed for five or more seconds after the previous receipt are not recognized as

parameters.

• Only one retry is made when a time-out is triggered. In this event, the resending is performed from the first byte of the

relevant command.

4. SENSE Commands

1. Electrical Specifications

Pin

No.

Signal

Operations Signal Direction

3

TXD Sending

data

HDR

→ CPU

2

RXD Receiving

data

HDR

← CPU

6

DSR

Data set ready

HDR

← CPU

5

GND Signal

earth

4

DTR Data terminal ready HDR

→ CPU

1 2

6

9

3 4 5

Output level

OFF: —5V or less
ON : +5V or more

D

0

D

1

D

2

D

3

D

4

D

5

D

6

D

7

0(SPACE) Start

1(MARX)

Stop

bit

bit

Configuration

TXD

RXD

CMD

ACK

200ms

ACK

ACK

Para1

Para2

TXD

RXD

CMD

DATA

200ms

200ms

DATA

RS-232C Interface