User manual
Protocol Analysis
R&S
®
RTO
280User Manual 1316.0827.02 ─ 06
Source: Tx, Rx
Select the input channels for the transmitter and receiver signals. Waveform 1 of channel
signals, math waveforms, and reference waveforms can be used for decoding. For trig-
gering on a serial bus, a channel signal is required.
SCPI command:
BUS<m>:UART:TX:SOURce on page 676
BUS<m>:UART:RX:SOURce on page 675
Threshold
Sets the threshold value for digitization of signals for each line. If the signal value on the
line is higher than the threshold, the signal state is high. Otherwise, the signal state is
considered low if the signal value is below the threshold. The interpretation of HIGH and
LOW is defined by the Polarity.
There are three ways to set the threshold:
●
"Threshold"
Enter the value directly in the field.
●
"Set to 50%"
Executes the measurement of reference levels and sets the thresholds to the middle
reference level of the measured amplitude.
●
"Preset"
Selects the default threshold voltage for various signal technologies from a list. The
value is set to "Manual" if the threshold was set with "Set to 50%", or was entered
directly.
SCPI command:
BUS<m>:UART:RX:THReshold on page 676
BUS<m>:UART:TX:THReshold on page 676
BUS<m>:UART:TECHnology on page 677
Polarity
Defines the logic levels of the bus. The idle state corresponds to a logic 1. the start bit to
a logic 0. "Idle high" (high=1) is used, for example, for control signals, while "Idle low"
(low=1) is defined for data lines (RS-232).
SCPI command:
BUS<m>:UART:POLarity on page 679
Bit rate
Sets the number of transmitted bits per second. To select a bit rate from list of predefined
values, tap the icon beside the "Bit rate" field. To enter a specific value, open the keypad.
The list of predefined values is also available in the keypad.
SCPI command:
BUS<m>:UART:BITRate on page 677
BUS<m>:UART:BAUDrate on page 678
Data bits
Sets the number of data bits of a word in a range from 5 to 8 bits.
SCPI command:
BUS<m>:UART:SSIZe on page 679
UART / RS232