RIGOL MSO/DS2000A Series - Manual (Page 123)

Chapter 5 To Trigger the Oscilloscope RIGOL
MSO2000A/DS2000A User’s Guide 5-37
RS232 Trigger
RS232 bus is a serial communication mode used in the data transimmision between
PCs or between PC and terminal. In RS232 serial protocol, a character is transimitted
as a frame of data which consists of 1 bit start bitm, 5~8 bits data bits, 1 bit check bit
and 1~2 bits stop bit(s). Its format is as shown in the figure below.
Figure 5-12 RS232 Trigger
MSO2000A/DS2000A oscilloscope triggers when the start frame, error frame, check
error or the specified data of the RS232 signal is detected.
Trigger Type:
Press Type to open the trigger type list. Rotate
and press down to select
“RS232”. At this point, the trigger setting information as shown in the figure below is
displayed at the upper right corner of the screen. For example,
Source Selection:
Press Source to open the signal source list and select CH1, CH2 or any channel of
D0-D15. For the details, please refer to the introduction in “Trigger Source”. The
current trigger source is displayed at the upper right corner of the screen.
Polarity
Press Polarity to select the polarity of date transmission. It can be set to “Normal”
or “Invert” and the default is normal.
Trigger Condition:
Press When to select the desired trigger condition.
 Start: trigger on the start frame position.
 Error: trigger when error frame is detected. After this trigger condition is
selected: