Pepper Computer Modular Computers RS232 User Manual

SMART I/O User’s Manual

©1996 PEP Modular Computers GmbH

March 12, 1996

Page 4 - 5

Chapter 4  Digital Modules

The SM-DIN1 provides 8 optoisolated 24V DC digital inputs arranged in 6

independent groups with respect to the ground connections. The maximum

input switching frequency is set to 200Hz with the system registering a

logical ‘1’ when the input exceeds 10V. Logical ‘0’ is returned when the

input falls below 8V. A low-pass filter restricts signals exceeding the filter

limit and registers a logical ‘0’ with the system. The user interface is realized

by 8 green LEDs (one per input channel) which illuminate when the input

exceeds 10V DC and a configurable filter on the last channel for INTx

interrupts (where ‘x’ lies between 1 and 4 depending on which slot the

module is located).

Isolation

2.5 kV optoisolated from the system

Input

8 Digital Channels (24V) DC 

±

 10%

6 Independent Groups
Common GND
< 5mA Input Current
Filter set to 200 Hz (5ms)
Overvoltage Protection (rate)
Overvoltage Protection (continuous)
Switch ON Delay
Switch OFF Delay
High Level
Low Level

: 300V/90

µ

s

: 35V
: 2ms (approx.)
: 2ms (approx.)
: > 10V
: < 8V

Front Panel

Green LEDs (ON when Input > 10V)

Options

User configurable R-C filter on the 
last channel for INTx generation

Power Consumption 5mW (min.), 100mW (max.)
Temperature Range

Standard (0

°

C to +70

°

C), Extended (-40

°

C to +85

°

C)

Module Weight

40g

ID Byte

$01, read by the SPI Interface