Specifications

RIGOL
4 M300 Selection Guide
Mixed-interface Separator Line
The mixed-interface separator line is used to convert the [RS-232/Alarms/Ext Trig] interface (25-pin
male) at the rear panel to two 9-pin interfaces. Wherein, one is a 9-pin male interface used as a standard
RS232 interface and the other is a 9-pin female interface used for alarm output and external trigger signal
input.
RS232: connect this interface with the PC via a RS232 serial cable (optional accessory) to build the
communication between M300 and the PC. You can program and control the instrument via the PC.
RS232 Interface
Alarms/Ext Trig: as shown in the figure below, pin 1 to pin 4 are used to output TTL pulse when an alarm
is generated in the corresponding alarm channel. Pin 6 is used to receive the external trigger signal.
When an external digital multimeter is connected for measurement, pin 5 and pin 6 are used together to
control the measurement.
Alarms/Ext Trig Interface
Pin
Definition
1
Alarm 1 Output
2
Alarm 2 Output
3
Alarm 3 Output
4
Alarm 4 Output
5
Channel Closed Output
6
Ext Trig Input/Channel Advance Input
7
GND
8
Not Used
9
Not Used
6
7
4
5
2
3
1
6
7
4
5
2
3
1
8
9
Pin
Name
Definition
1
--
--
2
RXD
Received Data
3
TXD
Transmitted Data
4
DTR
Data Terminal Ready
5
SGND
Signal Ground
6
DSR
Data Set Ready
7
RTS
Request To Send
8
CTS
Clear To Send
9
--
--
8
9
[RS-232/Alarms/Ext Trig] Interface