UNI-T UPO2000CS Series, User Manual

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UPO2000CS series User Manua
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Press the NEXT PAGE option key to enter the following settings:
Condition: Trigger Condition Settings
For the UPO2000CS series RS232 protocol, there are four kinds of trigger methods: Start of frame, error frame, parity error, and data.
Press the CONDITION option button and the trigger condition list will pop up. Press the CONDITION button again to switch between the
four modes. The Multipurpose knob can also set the trigger condition.

Start of Frame:
The waveform trigger is at the start bit of the RS232 protocol (referred to the drawing). Stable waveforms
can be observed by choosing the start of frame when single string signals or multiple same string signals are sent. If the data
being sent is changing, the waveform will also change correspondingly.

Parity Error
:
Set the RS232 parity bit to 0 or 1 according to the parity principles, the principles are as follows:

Odd parity: If the 1
st
bit is odd for data bit and parity bit, the transmission will be correct.

Even parity: If the 1
st
bit is even for data bit and parity bit, the transmission will be correct.
This function can quickly check the transmission process with parity error during RS232 communication, for ease of analyzing
and locating faults.

Error Frame :
The error frame can be classified to two kinds. One is parity error (odd or even error), the other is transmission
error. The transmission error conditions are as follows:
1. The signal is not set to 1 where there should be stop bits, then the frame data is wrong.
2.
When signals suddenly change and becomes unstable, this function can quickly test for transmission errors.

Data:
The waveform triggers when the data of BIT SETTING menu is equal to the data the oscilloscope is collecting. Note that
the data setting range is related to the data bit width. This function can quickly find the transmitting signals of particular data
set.
Polarity:
Set the signal polarity.
Normally, the positive polarity is used in RS232 protocol. The high level and low level stands for logic 1 and 0 respectively. Some users might
use negative polarity, which is that the high level and low level stands for 0 and 1 respectively. Therefore, the design is optimized to meet
demands from different users.
Choose the POLARITY option key, and the polarity selection list will pop up. Press the POLARITY option key again to switch between positive
polarity and negative polarity. The Multipurpose can also be used.
Bit Sequence
: Set the data bit sequence
Normally, the lower bit is transmitted first in RS 232 communication. For example: if bit [7:0] is transmitted, the bit [0] will be transmitted
firstly, and bit [7] transmitted last. Considering that users probably use MSB, that is, bit [7] is firstly. The transmitting methods can be set by
users.
Select the Bit Sequence option key, and the bit sequence selection list will pop up. Press the bit sequence again to switch between LSB and
MSB. The Multipurpose knob can also be used.
Baud Rate : Set the transmitting baud rate .
There are no clock signals for asynchronous serial communication. In order to analyze the data, the two communication parties need to
agree on the baud rate. Normally, the baud rate is defined as bits transmitted within 1 second. For example, 9600bps means that 9600 bits