Technical data

96 4000 X-Series Oscilloscopes Advanced Training Guide
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs
18 Tap the Parity softkey; then select Odd.
19 While this menu is active, also verity that the # of Bits is set to 8, the
Baud Rate is set to 19.2 kb/s, Polarity is set to Idle Low, and Bit Order is
set to LSB first.
20 Press the [Label] front panel key (between channel-1 and channel- 2
controls) to turn on the scope’s default labels.
You should now see RS232/UART decoding of these signals on your scope’s
display similar to Figure 61, but we still haven’t established stable
triggering. The scope is still triggering on any rising edge of channel-1
(default trigger condition). Let’s now set up the scope to trigger when the
transmit data signal (TX) is equal to 4D
HEX
.
21 Press the [Trigger] front panel key; then select Serial 1 (UART/RS232).
22 Tap the Trigger Setup softkey; then select Tx Data from the Trigger menu.
23 Tap the Data softkey; then select 0x4D using the Entry knob.
24 Set the scope’s timebase to 1.000 ms/div.
Figure 61 Decoding the RS232/UART serial bus.