4-8 Input / Output MN19024.3.4 Special functions on DIN4 and DIN5 - fast inputsFlex+DriveII only:DIN4 and DIN5 can be configured using the FASTSELECT keyword to perform specialfunctions:H Fast interrupt hardware position capture input. The position of the axis is captured in realtime and can be read using the Mint keyword FASTPOS.H Master or auxiliary encoder input capture, read using the Mint keywordFASTAUXENCODER(DIN5 only).The maximum latency to read the fast position is approximately 1μs. The fast interrupt will belatched on a pulse width of about 30μs, although a width of 100μs is recommended to ensurecapture. To prevent subsequent inputs causing the captured value to be overwritten, theinterrupt is latched in software. It is necessary to clear the latch before subsequent interruptscan be detected. See the Mint help file. Both inputs are fitted with Schmitt trigger devices.Note: The fast inputs are particularly sensitive to noise, so inputs must use shieldedtwisted pair cable. The inputs are not opto-isolated.Do not connect mechanical switches, relay contacts or other sources liable tosignal ëbounceí directly to the fast inputs. This could cause unwanted multipletriggering.Active high: DINx=+24VDC (±20%)CREF=0VCREFPin 7DINxPins 14-154k733pFHCPL2231to CPUVccFlexDriveIIActive low: DINx=0VCREF=+24VDC (±20%)1k10kDGNDFigure 27 - X3 pulse and direction / fast digital input circuit
