Somachine Configuration Software Page 6 SoMachine Basic programming software

6 Functions Position control SoMachine Basic provides three positioning software functions for the Modicon M221 logic controllers used, for example, for stepper motor control. b PLS function The PLS function block generates pulses of fixed ratio. In some cases, the frequency can be fixed and in others it is variable (as in control of slopes when driving a stepper motor). The %PLS function block can be programmed to generate a specific number of pulses. The %PLS function blocks are assigned to the %Q0.0 or %Q0.1 outputs of M221 logic controllers (1). The pulse generator signal has a variable period, but with a constant duty cycle which establishes an ON to OFF ratio of 50% of the period. b PWM function The PWM function block generates pulses of fixed frequency, with a variable ON to OFF ratio for the output signal. The ON to OFF duration ratio is a dynamic variable called %PWM.R, with a range from 1% to 100%. The PWM function blocks are assigned to the %Q0.0 or %Q0.1 outputs of M221 logic controllers (1). The %PWM function block, defined by the user, generates a signal on output %Q0.0 or %Q0.1 of M221 logic controllers. b Frequency generator function (FREQGEN) The Frequency generator function generates a square wave signal on the outputs of M221 logic controllers (1) with a fixed duty cycle (50%). The frequency can be configured from 0.1 Hz to 100 kHz with intervals of 0.1 Hz. Event processing Event management by the application. b Source types: v Events on embedded inputs v Threshold events on the high speed counter (HSC) v Periodic event (Timer) b Each event executes a single subroutine. Process control (PID) b 14 PID programming loops b Auto-tuning algorithm b Analog/PWM output b Linear conversion of measurement input b 2 alarm levels (high and low) on the measurement b Control output limits b Forward and reverse action PLS function PWM function Functions (continued) SoMachine Basic programming software For Modicon M221 and M221 Book logic controllers Position control, Event processing, Process control (PID)

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