Method and apparatus for multiplex control of a plurality of stepper motors
US5583410A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 1994 |
| Grant date | Dec 10, 1996 |
| Priority date | — |
| Expiry date | Oct 21, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/42198
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A plurality of step time tables consisting of a sequence of step times defining intervals between steps and thus a velocity profile to be executed by a stepper motor are stored in a first memory. A step table defining a plurality of identical sequences of excitation pattern for driving a stepper motor is stored in a second table. Identical DMA channels output the step times to a timer and the plurality of exitation patterns to a buffer. The timer measures the duration of the step times and when each step time expires generates a trigger signal which initiates the transfer of the next step time and next excitation pattern through the respective DMA channels. The buffer includes a control register which selects one excitation pattern from the plurality of excitation patterns output from the step table to be output for control of a selected one of a plurality of motors connected to the buffer. The buffer outputs are inverted to form bipolar signals to drive current drivers in accordance with the excitation pattern. The apparatus is initialized by a data processor to select one of the plurality of excitation tables and to select one of the groups of outputs of the buffer to drive a cor…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.