Scanlab RTC 5 PC Interface Board - set_encoder_speed

RTC
®
5 PC Interface Board
Rev. 1.9 e
10 Commands And Functions
418
innovators for industry
Delayed Short
List Command
set_encoder_speed
Function defines the target encoder speed and further parameters for encoder-speed-dependent
automatic laser control.
Call set_encoder_speed( EncoderNo, Speed, Smooth )
Parameters EncoderNo Number of the encoder counter to be used for speed measurement
as an unsigned 32-bit value,
allowed values:
= 0: Encoder counter Encoder0
= 1: Encoder counter Encoder1
= 2 and 3: vectorial encoder velocity: a vectorial velocity is calculated
from both encoder speeds (via the pulse rates of both encoder
counters) for use with encoder-speed-dependent automatic
laser control in
Mode = 5.
Higher bits are ignored.
Speed Target encoder speed (counter pulse rate) in [counter pulses/ms]
as a 64-bit IEEE floating point value;
allowed range: [100.0 … 16000.0]; for
Speed > 16000.0, Speed is
clipped to 16000.0, for 0.0 <
Speed < 100.0 to 100.0.
Smooth Smoothing factor for a 2-stage low-pass filter as a 64-bit IEEE floating
point value; allowed range: [0.0 … 1.0]; larger values will be clipped.
Comments • If Smooth = 0.0, then only the current encoder speed CurrentSpeed (based on counter
pulses received in the most recent 10 µs) will be used; if
Smooth = 1.0, then the speed
from the previous clock cycle
PreviousSpeed . In general, the used speed is:
Speed =
PreviousSpeed · Smooth + CurrentSpeed · (1.0 – Smooth ).
•If
Speed  0.0 or Smooth < 0.0, then set_encoder_speed will, already during loading,
be replaced by a list_nop (get_last_error return code
RTC5_PARAM_ERROR ).
• One encoder increment results in four counter pulses.
• The maximum value for
Speed (16000.0) corresponds to a counting rate of 16 MHz. The
minimum value for
Speed (100.0) corresponds to a counting rate of 1/(10 µs), i.e. one
counter pulse per output period. Beware of the low resolution of encoder-speed-depen-
dent laser control for low speed values! Encoder-speed-dependent correction is only
recommended if substantially more than one counter pulse per output period (10 µs)
are received.
• Also see "Encoder-Speed-Dependent Laser Control", page 148.
RTC
®
4  RTC
®
5new command
Version info Last change with version DLL 536, OUT 536:
EncoderNo = 2 and 3
References set_encoder_speed_ctrl, set_auto_laser_control