Agilent Technologies DSO-X 4022A, User Manual

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468 Agilent InfiniiVision 4000 X-Series Oscilloscopes User's Guide
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UART/RS232 Triggering and Serial Decode
• When the horizontal scale setting does not permit the display of all
available decoded data, red dots will appear in the decoded bus to
mark the location of hidden data. Expand the horizontal scale to allow
the data to display.
• An unknown (undefined) bus is shown in red.
• A parity error will cause the associated data word to be shown in red,
which includes the 5- 8 data bits and the optional 9th bit.
UART/RS232 Totalizer
The UART/RS232 totalizer consists of counters that provide a direct
measure of bus quality and efficiency. The totalizer appears on screen
whenever UART/RS232 Decode is ON in the Serial Decode Menu.
The totalizer is running, counting frames and calculating the percentage of
error frames, even when the oscilloscope is stopped (not acquiring data).
The ERR (error) counter is a count of Rx and Tx frames with parity
errors. The TX FRAMES and RX FRAMES counts include both normal
frames and frames with parity errors. When an overflow condition occurs,
the counter displays
OVERFLOW
.
The counters can be reset to zero by pressing the Reset UART Counters
softkey in the UART/RS232 Settings Menu.