diff --git a/prod/doc/setup.hmac b/prod/doc/setup.hmac index c0fb4c6..be660fa 100644 --- a/prod/doc/setup.hmac +++ b/prod/doc/setup.hmac @@ -164,6 +164,11 @@ if the host name or IP address under which the Ben is reached differs from "ben", the value of ATBEN_DUT and ATUSB_REF will have be changed accordingly.
+The Makefile also contains the variable SPECTRUM_MARGIN that +defines how many dB of tolerance should be allowed below and above the +reference signal strength. The default is to allow a margin of 5 dB in +either direction. +
The scripts atusb and atusb-flash also contain
configuration variables. If the names of the files containing the
atusb firmware binaries are not boot.hex and
@@ -369,7 +374,32 @@ Ben, and if a stable temperature is maintained.
+The physical arrangement of the devices should have the characteristics
+described in the test section. The orientation
+of the devices should be chosen such that the overall signal strength is
+near its maximum, that the spectrum is relatively "flat", and that small
+changes in the orientation only produce small variations in the measured
+signal strength.
+
+To generate the profiles for atben and atusb, simply run
+
+After a obtaining the reference spectrum, press Q to exit. The
+Makefile will then record the signal strength limits for an atben
+DUT in the file ben.profile and proceed with the reverse
+measurement, i.e., with atusb acting as the DUT.
+The two devices should be about 1 m apart, with as few metal or watery
+objects between or near them as possible. Location and orientation should
+be easily reproducible, e.g., by marking the device's edges on the table
+with tape. Other transmitters in the 2.4 GHz band will interfere with
+measurements and should be kept as far away and as inactive as possible.
+
+make spectrum
+
+Then place the devices appropriately and press D in the measurement
+window to use the displayed spectrum as the reference. Multiple spectra
+can be merged into the reference, e.g., if environmental conditions cause
+significant variations. Spectra included in the reference are shown in blue.
+