초록 ▼

A system for controlling a stepper motor is disclosed that includes a microprocessor for directly generating current command signals. The microprocessor has a memory wherein the memory includes a function table, a first function table address, and a second function table address. A velocity signal (

A system for controlling a stepper motor is disclosed that includes a microprocessor for directly generating current command signals. The microprocessor has a memory wherein the memory includes a function table, a first function table address, and a second function table address. A velocity signal (indicating a rotational position change per unit time) is calculated by the microprocessor during each update interval. Each update interval comprises a plurality of interrupt intervals. The microprocessor, in accordance with software-selectable current magnitude parameter values and microstepping parameter values, determines a first and second current value by accessing the function table at the first and second function table addresses, during each interrupt interval. The first and second current values generated by the microprocessor correspond to a pair of digital words representing a pair of phase current commands. The microprocessor outputs the pair of digital words to a drive circuit during each interrupt interval to energize a two-phase stepper motor.

대표청구항 ▼

[ What is claimed is:] [2.] A method of controlling a motor, said method comprising the steps of:(A) generating a first current value from a function table, said first current value corresponding to an excitation waveform for said motor;(B) storing said first current value in a first transfer table;

[ What is claimed is:] [2.] A method of controlling a motor, said method comprising the steps of:(A) generating a first current value from a function table, said first current value corresponding to an excitation waveform for said motor;(B) storing said first current value in a first transfer table; and,(C) repeating steps (A) and (B) a plurality of times corresponding to the number of entries to be output from said first transfer table during a first update interval. [14.] An apparatus for controlling a motor, comprising:means for generating a velocity signal during a first update interval, said first update interval including a plurality of interrupt intervals and said velocity signal corresponding to a desired change in rotational position of said motor per unit time;means for dividing said change in said rotational position by a predetermined number to obtain an incremental position change value;means for generating a first current value from a function table during a first interrupt interval of said plurality of interrupt intervals using said incremental position change value; andmeans for generating a first current in said motor during said first interrupt interval responsive to said first current value.