Patent · US Expired

Signal tracing control system for PMC

US4812964A · kind A · utility

3Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 25, 1987
Grant dateMar 14, 1989
Priority date
Expiry dateNov 25, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/13142
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A signal tracing control system provided in a programmable machine controller (PMC) which controls a machine in response to a signal from a numerical control apparatus. A signal of a monitored RAM (1) is monitored for a change by a monitoring circuit (21). When a signal change is detected by the signal monitoring circuit (21), it applies a signal to a writing control circuit (22) which then writes the data of the monitored RAM (1) into a tracing buffer (2). This cycle of operation is repeated. Thus, only when a data item in the monitored RAM (1) is changed, is the signal traced. Effective signal tracing can therefore be effected with a small memory capacity.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.