MicroE Systems Dual Axis Averager Mercury 3000Si, Installation And Reference Manual

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FFrriin ng ge e C Co ou un ntte err S Siizze e
The M3000SiDAA allows the user to configure the serial word to increase sampling rate. Some applications do not
require 18 bits of fringe count. The SPI Settings box allows the user to reduce the fringe counter to suit the applica-
tion and thereby increasing the maximum sampling rate of the system.
S SP PII O Ou uttp pu utt FFo orrm ma att
The format of the SPI output can be configured to have the status word at the beginning or at the end of the serial
word.
S SP PII M Mo od de ess
There are two different SPI modes the users can select from:
Free Running or Standard communication mode latches the output buffer with the current data when the
falling edge of Chip Select is asserted.
The Trigger Acquisition mode can be used in applications where synchronization of the position data to an
event is required. Often, this mode is used when a fixed latency between a clock signal and the sampled
position data is required. If this option is selected a new calculation cycle starts each time the falling edge
of Chip Select is asserted. NOTE: This mode is equivalent to the SS-350cSI Trigger line. It use the falling
edge of the cs as trigger
IIn nd de exx M Mo od de e S Se ettttiin ng gss::
Configure how the serial word data is manipulated when encountering the index angle position.
M Ma asstte err C Ch hiip p S Se elle ec ctt
Allows one hardware Chip Select to be used for all channels to minimize wiring connections.
FFe ee ed db ba ac ckk C Cllo oc ckk S Se elle ec ctt
Allows the user to select the optional Feedback clock. The Feedback clock signal is used to eliminate propagation
delays due to long cable lengths.
C CR RC C S Se ettttiin ng g
Allows the user to generate a CRC (Cyclic Redundancy Check). The CRC is located within the status word. The CRC
is only valid when the status byte is at the end of the serial word (see S
SP PII O Ou uttp pu utt FFo orrm ma att above) and the wholw
fringes (18 bits) are read.
Note: The polynomial used for CRC calculation is 10011. The resulting checksum is 4 bits and performed on the 28
bits position word only, the status bits are not used in the CRC calcualtion.
M3000SiDAA Configuration
C Ch ha an nn ne ell 11 & & 22 C Ca alliib brra attiio on n S Se ettttiin ng gss
If two separate axes are used the recommended setting is "Calibrate signal and center index". For applications where two
sensors are used on the same axis or if the index mark is not in the range of motion for one of the encoders, the "Calibrate
signal only" will allow proper calibration of the signal.
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Warning: Changing configuration settings while in closed loop control is not recommended.
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