Rohde & Schwarz R&S FSP Series, Operating Manual

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R&S FSP Maintenance and Instrument Interfaces
Instrument Interfaces
8.10 Operating Manual 1164.4556.12 - 06
Hardware handshake
For hardware handshake, the instrument indicates that it is ready to receive data via
the lines DTR and RTS. A logic '0' on both lines means 'ready' and a logic '1' means
'not ready'. The RTS line is always active (logic '0') as long as the serial interface is
switched on. The DTR line thus controls the readiness of the instrument to receive
data.
The readiness of the remote station to receive data is reported to the instrument via
the CTS and DSR line. A logic '0' on both lines activates the data output and a logic
'1' on both lines stops the data output of the instrument. The data output takes place
via the TxD line.
Cable for hardware handshake
The connection of the instrument to a controller is made with a so-called zero
modem cable. Here, the data, control and acknowledge lines must be crossed. The
following wiring diagram applies to a controller with a 9-pin or 25-pin configuration.
Fig. 8.6 Wiring of the data, control and acknowledge lines for hardware handshake
Controller
25-pin
Instrument
9-pin
1
2
3
4
5
6
7
8
9
Controlller
9-pin Instrument
9-pin
1
2
3
4
5
6
7
8
9
1
3
2
6
5
4
8
7
9 8
2
3
6
7
20
5
4
22
RxD / TxD
TxD / RxD
DTR / DSR
GND / GND
DSR / DTR
RTS / CTS
CTS / RTS
RxD / TxD
TxD / RxD
DTR / DSR
GND / GND
DSR / DTR
RTS / CTS
CTS / RTS