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3-6-2-2. UART Serial Bus Configuration
The UART bus menu is designed to decode RS-232 and other
common RS-232 variants such as RS-422, RS-485. The software
configuration is also flexible enough to decode the many proprietary
protocols based on RS-232.
Background
Basic RS-232 protocol uses single-ended data
transmissions. The signal voltage levels can be
high (±15V) and employ active low signaling.
High speed variants of RS-232, such as RS-422
and RS-485 use differential signaling and
commonly employ low voltage differential signals
with active high signaling.
Universal Asynchronous Receiver/Transmitter
(UART) or RS-232 driver/receiver ICs commonly
used for embedded applications typically use
active high signaling with standard IC signal levels.
Operation
1. Connect each of the bus signals (
Tx
,
Rx
) to one
of the oscilloscope channels. Connect the
ground potential of the bus to one of the probes’
ground clip.
GND
Rx
Tx
X10
X1
X10
X1
2. Press the
BUS
key.
BUS
B
3. Press
Bus
from the bottom menu
and choose the
UART
serial bus
on the side menu.
Define Inputs
1. Press
Define Inputs
from the
bottom menu.
2. From the side menu choose the
Tx
Input
and the
Rx
Input
source and the signal
polarity.
Tx
OFF, CH1 ~ CH4
Rx
OFF, CH1 ~ CH4
