R?1,W Read W&F weighted, W&F unweighted, speed and phase
R?1,+ Read source ID text (up to 21 characters sent via FSK)
To avoid any risk of the remote computer mis-interpreting the results, the format is
always fixed: distortion results are always returned in dB relative to the level of the
fundamental (never in percent, regardless of the configuration setting) and Test Level
results are always in absolute dBu. Other results are as for normal sequence operation:
noise and crosstalk results in dB relative to the measured Test Level (see section 3.10);
speed errors (as measured by segment W) in %; phase results in degrees; user level and
MOL results (segments K and H) are in absolute dBu. See section 9.6 for another
example. If necessary the distortion results can be converted to a percentage using the
following equation:
dB to % conversion converting dB to % % conversion Percent from dB distortion results in %
where d is the level of distortion in dB and p is the level as a percentage (ie -20dB=10%).
Normalised frequency response results can be read using this command and the
corresponding levels for the frequencies shown in table 3.2 will be returned (with the
normalisation operating as described in section 3.16). These are the same as the values
which are printed and used for tolerance testing. The full 256 point frequency response
data can be read using the S? command (see below), and this is essential if high-
resolution graphs are to be plotted.
Read Results with Measurement Level: 2RR?r,xxx... RR? Read results
This command is the same as the 2R? command described above but it also returns the
segment measurement level before the segment results (on a single line terminated with a
CR character). This measurement level is transmitted in the FSK segment header from
the LA101, and is printed in the header line of each segment (see fig. 3.9). A full
explanation of measurement levels is given in section 4.4.
Print Results: 2PR
PR print sequence results
This command will cause the LA102 to output the sequence results in a format suitable
for printing. This will include printer control codes (and graphics data) so this command
is normally used when the data is to be passed on to a printer by the controlling computer.
Configuration P will be used to determine which printer control codes should be used and
setting P0 will cause printer control codes and graphics data to be omitted providing a
simple way of obtaining sequence results from the unit. Lines will be terminated with
Line Feed characters (ASCII 10), and pages will be terminated with Form Feed (ASCII
12) characters. Note that LF and FF characters may also appear within the binary
graphics data which is used to print graphs. There is no specific end-of-printout code, but
the busy line will indicate that the LA102 is ready for data when it has finished.
(Alternatively, if no data is sent for 1s, it may be assumed that the LA102 has finished).
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9. Remote Control
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