GW Instek GBS-1000 Series Programming Manual - Manual (Page 9)

CONFIGURATION
9
Range None, Odd, Even
9. Connect the RS-232C cable
to the rear panel port: DB-9
male connector.

Pin assignment 1 2 3 4 5
6 7 8 9
2: RxD (Receive data)
3: TxD (Transmit data)
5: GND
4, 6 ~ 9: No connection
PC connection Use the Null Modem connection as in the below
diagram.
GBS - 1000 PC
TxD
RxD
GND
Pin 2
Pin 3
Pin 5
RxD
TxD
GND
Pin 2
Pin 3
Pin 5