Select termination for the module, Base module to expansion interface – Rockwell Automation 1791R-XXXX CompactBlock Distributed I/O on Remote I/O Series D I.I. User Manual

Page 19

Advertising
background image

CompactBlock Distributed I/O on Remote I/O Series D 19

Publication

1791R-IN002B-EN-P - August 2003

Select Termination for the Module

The terminator resistor is provided in the module. Use the DIP switches to
select termination for the module. See below.

Base Module to Expansion Interface

The base module is linked to the expansion module with an 8-bit parallel bus,
control lines, Vcc and ground connections, a reset/initialization line, and an
expansion presence line. The 8-bit bus is multiplexed so that 16 bits of data (1
for each I/O point) can be transmitted/received with two transfers. The
reset/initialization line is used during initialization of the module. The
presence line is used for the detection of an expansion module at power up
and for a period of each data transfer. Module ID is read over this bus at
power up.

1791R modules supply expansion power via expansion bus as follows:

Expansion power voltage

5Vdc

Expansion power current

100mA

Switch

SW1

SW2

ON

Terminator on *1

Terminator on **2

OFF

No Terminator

No Terminator

* 1 at baud rate 230.4KBPS.

**2 at baud rate 57.6KBPS or 115.2KBPS.

Line 1

SW1

82 ohm

Line 2

SW2

150 ohm

43107

Advertising