Chapter 3 Front-Panel Operation

RS-232 Interface Configuration

DB-25 Serial Connection If your computer or terminal has a 25-pin serial port with a male connector, use the null-modem cable and 25-pin adapter included with the Agilent 34398A Cable Kit. The cable and adapter pin diagram are shown below.

Instrument

DCD

RX

TX

DTR

GND

DSR

RTS

CTS

RI

 

 

 

5182-4794

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cable

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

 

 

 

 

 

 

 

 

 

 

 

2

 

 

 

 

2

3

 

 

 

3

4

 

 

 

 

 

 

 

4

5

 

 

 

 

 

 

 

 

 

 

 

 

5

 

 

 

 

 

 

 

 

 

 

6

 

 

 

 

 

 

 

 

 

6

 

 

 

 

7

 

 

 

 

 

 

 

 

 

 

7

 

 

 

 

 

 

 

8

 

 

 

 

 

 

 

 

 

 

8

 

 

 

 

 

 

 

9

 

 

 

 

 

 

 

 

 

 

9

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

2

3

4

5

6

7

8

9

5181-6641

 

Adapter

PC

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2

 

TX

 

 

 

 

 

 

 

 

 

 

 

 

 

3

 

RX

 

 

 

 

 

 

 

 

 

 

 

 

 

4

 

RTS

 

 

 

5

 

CTS

 

 

 

 

 

 

 

 

 

6

 

DSR

 

 

 

 

 

 

 

 

 

7

 

GND

 

 

 

 

 

 

8

 

DCD

 

 

 

 

 

20

 

DTR

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DB9

DB9

DB9 DB9

Male

Female

Female Male

DB25 DB25 Female Male

DTR / DSR Handshake Protocol

The power supply is configured as a DTE (Data Terminal Equipment) device and uses the DTR (Data Terminal Ready) and DSR (Data Set Ready) lines of the RS-232 interface to handshake. The power supply uses the DTR line to send a hold-off signal. The DTR line must be TRUE before the power supply will accept data from the interface. When the power supply sets the DTR line FALSE, the data must cease within 10 characters.

To disable the DTR/DSR handshake, do not connect the DTR line and tie the DSR line to logic TRUE. If you disable the DTR/DSR handshake, also select a slower baud rate to ensure that the data is transmitted correctly.

The power supply sets the DTR line FALSE in the following cases:

1When the power supply’s input buffer is full (when approximately 100 characters have been received), it sets the DTR line FALSE (pin 4 on the RS- 232 connector). When enough characters have been removed to make space in the input buffer, the power supply sets the DTR line TRUE, unless the second case (see next) prevents this.

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Image 65
Agilent Technologies E3632A manual DTR / DSR Handshake Protocol