STEP_DIR (150)

STEP_DIR (150)

ID                          150

Group: MOTION

Short description:

Function that controls the stepper motor.

Inputs (2):

Outputs: none

Settings:

Function operation:

The STEP_DIR function is used to set the current frequency of the STEP (STEP) signal and the DIRECTION (DIR) signal to control a stepper motor or a servo drive operating in the position control mode with STEP / DIR signals. The Out_channel variable specifies the number of channels to which the drive is attached. The direction variable specifies the direction of travel for positive speed. For direction = 1, the DIR output will be 1 with the positive set speed signal. For direction = -1, the DIR output will be 0 with a positive set speed signal (table B.150.1).

For the step / direction outputs to work, the special marker M1024 must be activated. 

dpos - set position, dposp - current position

table B.150.1. Effect of Direction settings on the DIR output signal

The enable signal enables control of the STEP / DIR outputs. When the enable signal is off, there is no control and the STEP and DIR outputs are low. Make sure that the enable signal is turned on before starting to control the drive. The frequency of the physical STEP output is calculated by the formula:
Pulse frequency = pos_scale_factor * (dpos - dposp) * R3600 [imp./s]

where:

dpos - set position [user units]

dposp - current position [user units]

pos_scale_factor - scaling factor [-]

R3600 - Control_Loop_Frequency - special register defining the frequency of the control loop [Hz]

If the calculated frequency is higher than allowed for a given channel, pulses with the maximum frequency determined by the values ​​in the R3471, R3472, R3473, and R3474 registers will appear on the output.

The pos_scale_factor coefficient is used to rescale the set position value to the position in pulses.

For activation, it is necessary to set _STEP_Max_Fre for the given channel (210000).

R registers and M markers used: