User manual

PDx-113-57/60-SE / TMCM-113-57/60-SE Firmware Manual (V1.10 / 2009-OCT-28) 67
Copyright © 2009, TRINAMIC Motion Control GmbH & Co. KG
Number
Axis Parameter
Description
137
acceleration divisor
A ramping parameter, can be adjusted in special cases,
automatically calculated by setting the maximum
acceleration (e.g. during normal initialization). See the
TMC428 data sheet for details. Normally no need to
change.
138
ramp mode
Automatically set when using ROR, ROL, MST and MVP.
0: position mode. Steps are generated, when the
parameters actual position and target position differ.
Trapezoidal speed ramps are provided.
2: velocity mode. The motor will run continuously and
the speed will be changed with constant (maximum)
acceleration, if the parameter "target speed" is changed.
For special purposes, the soft mode (value 1) with
exponential decrease of speed can be selected.
140
microstep resolution
0 – full step *)
1 – half step *)
2 – 4 microsteps
3 – 8 microsteps
4 – 16 microsteps
5 - 32 microsteps**)
6 – 64 microsteps**)
Modifying this parameter effects the rotation speed in
the same relation:
*) The full-step setting and the half-step setting are not
optimized for use without an adapted microstepping
table. These settings just step through the microstep
table in steps of 64 respectively 32. To get real full
stepping use axis parameter 211 or load an adapted
microstepping table.
**) If the module is specified for 16 microsteps only,
switching to 32 or 64 microsteps brings an enhancement
in resolution and smoothness. The position counter will
use the full resolution, but, however, the motor will
resolve a maximum of 24 different microsteps only for
the 32 or 64 microstep units.
141
ref. switch tolerance
For three-switch mode: a position range, where an
additional switch (connected to the REFL input) won't
cause motor stop.
142
snapshot position
For referencing purposes, the exact position at hitting of
the reference switch can be captured in this parameter. A
dummy value has to be written first to prepare caption.
143
max. current at rest
In contrast to the standby current, this current limit
becomes immediately active when the motor speed
reaches zero. The value represents a fraction of the
absolute maximum current:
0 – no change of current at rest (default, 100%)
1…7 – 12.5% …87.5%
See the TMC428 datasheet for details. Normally not used,
use parameters 6 and 7 instead!
144
max. current at low accel.
An optional current reduction factor, see parameters 136
and 143 for details. Normally not used, use parameters
6 and 7 instead!
145
max. current at high
accel.
An optional current reduction factor, see parameters 136
and 143 for details. Normally not used, use parameters
6 and 7 instead!