Sutter Instrument TRIO MP-235, Руководство по эксплуатации

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TRIO MP-235 THREE-AXIS MICROMANIPULATOR SYSTEM OPERATION MANUAL – REV. 2.23 (20190130) (FW V2.2 & 2.3)
“unsigned long”; “U32” for LabVIEW. Although a signed type might be desirable for
computation and compatibility purposes, the application must ensure that only unsigned
longs or U32 values are sent to, and received from, the controller (i.e., no negative values).
5. All 32-bit position values transmitted to, and received from, the controller must be
bit/byte-ordered in “Little Endian” format. This means that the least significant bit/byte
is last (last to send and last to receive). Byte-order reversal may be required on some
platforms. Microsoft Windows, Intel-based Apple Macintosh systems running Mac OS X,
and some Intel/AMD processor based Linux distributions handle byte storage in Little-
Endian byte order so byte reordering is not necessary before converting to/from 32-bit
“long” values. LabVIEW always handles “byte strings” in “Big Endian” byte order
irrespective of operating system and CPU, requiring that the four bytes containing a
microsteps value be reverse-ordered before/after conversion to/from a multibyte type value
(I32, U32, etc.). MATLAB automatically adjusts the endianess of multibyte storage
entities to that of the system on which it is running, so explicit byte reordering is
generally unnecessary unless the underlying platform is Big Endian. If your development
platform does not have built-in Little/Big Endian conversion functions, bit reordering can
be accomplished by first swapping positions of the two bytes in each 16-bit half of the 32-
bit value, and then swap positions of the two halves. This method efficiently and quickly
changes the bit ordering of any multibyte value between the two Endian formats (if Big
Endian, it becomes Little Endian, and if Little Endian, it becomes then Big Endian).
6. “Move” commands might have short to long distances of travel. If not polling for return
data, an appropriate delay should be inserted between the sending of the command
sequence and reception of return data so that the next command is sent only after the
move is complete. This delay can be auto-calculated by determining the distance of travel
(difference between current and target positions) and rate of travel. This delay is not
needed if polling for return data. In either case, however, an appropriate timeout must be
set for the reception of data so that the I/O does not time out before the move is made
and/or the delay expires.