ST L6472, Manual

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L6472 Functional description
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6.5 Absolute position counter
An internal 22-bit register (ABS_POS) keeps track of the motor motion according to the
selected step mode; the stored value unit is equal to the selected step mode (full, half,
quarter, etc.). The position range is from -2
21 to +2 21 -1 (µ) steps (see Section 9.1.1 on page
41 ).
6.6 Programmable speed profiles
The user can easily program a customized speed profile, independently defining
acceleration, deceleration, maximum and minimum speed values through the ACC, DEC,
MAX_SPEED and MIN_SPEED registers respectively (see
Section 9.1.5 on page 42 , 9.1.6
on page 42 , 9.1.7 on page 43 and 9.1.8 on page 43 ).
When a command is sent to the device, the integrated logic generates the microstep
frequency profile that performs a motor motion compliant to speed profile boundaries.
All acceleration parameters are expressed in step/tick 2 and all speed parameters are
expressed in step/tick; the unit of measurement does not depend on selected step mode.
Acceleration and deceleration parameters range from 2
-40
to (2
12
-2) • 2
-40
step/tick2
(equivalent to 14.55 to 59590 step/s2).
Minimum speed parameter ranges from 0 to (2 12 -
1
) • 2 -24 step/tick (equivalent to 0 to 976.3
step/s).
Maximum speed parameter ranges from 2 -18 to (2 10 -1) • 2 -18 step/tick (equivalent to 15.25 to
15610 step/s).
6.7 Motor control commands
The L6472 can accept different types of commands:

constant speed commands (Run, GoUntil, ReleaseSW)

absolute positioning commands (GoTo, GoTo_DIR, GoHome, GoMark)

motion commands (Move)

stop commands (SoftStop, HardStop, SoftHiz, HardHiz).
For detailed command descriptions refer to Section 9.2 on page 54 .