Tektronix 071-0590-00 user manual RS-232 Interface Hardware/ Handshaking Considerations

Using GPIB, RS-232

RS-232 Interface Hardware/ Handshaking Considerations

The remote interface consists of a 25-pin female D-type connector on the rear panel. When using the RS-232C interface, connect the controller to the GB1400 with an appropriate 25-pin cable. The GB1400 is configured as an RS-232C DCE (Data Circuit terminating Equipment). For a local (direct) connection to a DTE device (most RS-232C controllers), connect the controller to the GB1400 with a straight (non-null modem) cable. To connect to another DCE device, you need a null modem to cross-connect signal pairs 2 & 3, 4 & 5, and 6 & 20.

Refer to the following table for RS-232C signal names, pinouts, and functional descriptions.

Pin	Name	Function
1	GND	Protective Ground
2	RxD	Received Data Input
3	TxD	Transmitted Data Output
4	CTS	Clear to Send (See note)
5	RTS	Request to Send (always high)
6	DTR	Data Terminal Ready (always high)
7	GND	Signal Ground
20	DSR	Data Set Ready
All other pins		Not used

Note: Sent to the GB1400, a high-level indicates that external device is ready to accept data from the unit. This pin must be high or open for the BERT to transmit data. This pin is pulled high internally by 27K Ohm to +12V.

RS-232 Interface Testing

To test that the RS-232C interface is properly connected, attach a standard 25-pin D-type connector cable between the RS-232C rear panel connector and the controller, with the GB1400 turned off. Turn on the GB1400. The following message should appear on the RS-232C controller’s screen, followed by the GB1400>.

****GB1400 RECEIVER VX.X GB1400>

NOTE: V X.X indicates the unit's software version . The "GB1400>" line is a prompt message indicating that the GB1400 is ready to accept a command.

If the message does not appear, check the following:

The cable may be defective.

The controller may be configured as DCE equipment. A null modem may be needed.

The controller signal format or BAUD rate may not match the GB1400's settings. Refer to the first part of this section for interface setting

GB1400 User Manual D-9