microDXP Technical Reference Manual
Version 3.15
October 7, 2019
33
The RS-232 command to read the diagnostic trace is 0x11. Please refer to the RS-232
Command Specification for details.
2.8.1.1
Trace Type (TRACETYPE)
Trace Type
(TRACETYPE) selects the vector that is acquired.
Note
: all of the Trace Type signals except for
ADC
and
ADC Average
are signed 2’s
complement vectors that have been sign-extended or attenuated to 16-bit magnitude, and
the sign-bit has been inverted such that 0 is shifted to 32,768.
Trace Type
TRACETYPE
Description
ADC
0
The raw ADC samples (with optional
inversion according to the
Polarity
setting)
ADC Average
1
A running average of the ADC
samples, where the average length is
equal to the
Baseline Average
Length
Fast Filter
2
The fast trigger filter output after fast
baseline subtraction, scaled to the
same units as the
Trigger Threshold
Raw Intermediate Filter
3
The output of the intermediate
baseline filter, before baseline
subtraction
Baseline Samples
4
Samples of the raw intermediate filter
when at baseline
Baseline Average
5
A running average of the
Baseline
Samples
, where the average length is
equal to the
Baseline Average
Length,
that is subtracted from both
the intermediate and energy filters
Scaled Intermediate Filter
6
The intermediate baseline filter after
baseline subtraction and scaling by
the digital gain coefficient
Raw Energy Filter
7
The output of the slow energy filter,
before baseline subtraction
Scaled Energy Filter
8
The slow energy filter after baseline
subtraction and scaling by the digital
gain coefficient
Table 2-4: Trace Type definitions
2.8.1.2
Sampling Interval (TRACEWAIT)
The
Sampling Interval
(TRACEWAIT) sets the time between individual points in the
trace, and ranges up from the ADC sampling interval, e.g. 25 ns for 40 MSPS.
Sampling Interval = (TRA 1) * ADC sampling interval
Equation 2-10
TRACEWAIT
Sampling Interval (40 MSPS)
Sampling Interval (80 MSPS)
0 (min)
25 ns
12.5 ns
