Research Concepts RC2000A - Manual (Page 74)

74 RC2000A Dual Axis Antenna Controller Appendix E Communications Protocol
from this byte and bytes 24 and 25, use
the following formula ...
internal_position = ((byte_24_25_position
* 661) / 99) + ls_nibble_byte_32
where ...
internal_position ... is the controller's
internal polarotor position
representation.
byte_24_25_position ... is the polarotor
position reported via byte 24 and 25 of
the device status poll reply and
displayed on the user interface (a value
in the range of 0 to 98).
ls_nibble_byte_32 ... is the least
significant nibble (lower 4 bits) of this
byte.
Note that in the above equation the
division is an integer division which
means that the result of the division
should be rounded DOWN to the closest
integer value (i.e (39 * 661) / 99 = 260.
When a polarotor is present in the system
the upper nibble of byte 32 will be
'0010'.
For the rotating feed, the internal
polarization position and the
polarization position displayed via the
user interface are the same and will be a
value in the range of 0 to 1023. For the
rotating feed the user is prompted to set
CW and CC limits. When the polarization
position is less than or equal to the CW
limit specified by the user the 'CW'
banner will be displayed. When the
polarization position is greater than or
equal to the CC limit specified by the
user, the CC banner will be displayed.
The polarization position given by bytes
24 and 25 of the device status poll reply
will be a value in the range of 0 to 92.
When the rotating feed is at a limit (or
beyond) the byte 24,25 values will be
'CW' or 'CC'. To obtain the internal
polarization position for the rotating
feed from this byte and the value in
bytes 24 and 25, use the following
formula ...
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