Pepper Computer RS232, RS485 user manual Sm-Ssi, Introduction

Chapter 6 Communications Modules SMART I/O User’s Manual

6.2SM-SSI

6.2.1Introduction

The SM-SSI is an optoisolated single-channel, 24-bit RS422 interface for absolute encoders. Configurable data input together with flexibility afforded by software configurable encoder types transforms this SMART Module into an intelligent interface suitable for the most demanding applications. Data flow is indicated by the presence of two red LEDs on the front panel.

6.2.2 Specifications

Isolation	2.5 kV optoisolated from the system
Input	1 optoisolated SSI channel, 24-bit binary or Gray code
	(software configurable), RS422 type
	2 optoisolated 24V DC digital inputs for common GND and
	End-of-Range switches with readback and IRQ support
Output†	2 optoisolated 24V DC/300mA digital outputs for Encoder
	Reset and Encoder Direction
	1 optoisolated 24V DC/300mA digital output for Match
SSI Interface	None, Even or Odd (software configurable), Data, Parity
	Software configurable (data bits, parity) encoder type
	Software detection of line break
	SSI defined, RS422 type Clock Output
	62.5, 125, 250 or 500kHz (programmable) Tx. Pulse Freq.
	Data flow controlled by software and indicated by LED status
	Up to 24-bit Compare Register with pass-through compare
	Interrupt, software and LED control of Match Result
Front Panel	2 Red LEDs indicating MATCH and data conversation
Ext. Vcc	24V DC (±5%)
Power Cons.	325 mW (min.), 375mW (max.)
Temperature Range	Standard (0˚C to +70˚C), Extended/Storage (-40˚C to +85˚C)
Operating Humidity	0% to 95% (non-condensing)

†All outputs are referenced to the common Ext. Vcc

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October 01, 1996 ©1996 PEP Modular Computers GmbH Page 6 - 17