Rockwell Automation 1771-DB BASIC MODULE - Manual (Page 334)

Product Overview
Appendix A
A –2
Hardware Features
Hardware element Description
Reset switch When you press this switch (located behind the module ejector tab), the
BASIC module initiates a full reset. The BASIC module reacts to this
reset the same as it does when you turn on power to your I/O chassis
backplane.
LED indicators 10 LED indicators for module diagnostics and operator indicators.
•
8 pre-defined LED indicators
•
2 user-defined LED indicators
DH485 port This RJ-45 port (DH485) provides communication over the DH-485
network.
Use DH485 port to interface the BASIC module with the DH-485 network.
This port is not isolated and cannot directly drive the DH-485 network.
You must use a 1747-AIC link coupler to link port DH485 with the DH-485
network. You can also use this port as a program port.
PRT2 port This independently configurable, isolated 25-pin D-shell serial port
provides RS-232, RS-422, and RS-485 communication with I/O devices.
Use PRT2 to interface the BASIC module with user devices or a modem
using DF1 protocol. PRT2 provides DF1 full–duplex or half–duplex slave
protocol for SCADA applications. PRT2 is capable of operating full–duplex
at 300, 600, 1200, 2400, 4800, 9600, and 19200 bit/s. It is electrically
isolated to 500V dc.
PRT1 port This independently configurable, isolated 25-pin D-shell serial port
provides RS-232, RS-422, and RS-485 communication with I/O devices.
Use PRT1 to interface the BASIC module with user devices. PRT1 is
capable of operating full–duplex at 300, 600, 1200, 2400, 4800, 9600, and
19200 bit/s. It is electrically isolated to 500V dc. You can also use this
port as a program port.
RAM 24K bytes of battery backed RAM for storage of user programs and data
Battery backup
•
battery-backed, 24-hour clock/calendar
•
capacitive backup of RAM during battery change
Memory module
•
socket for a standard EEPROM or pre-programmed EPROM memory
module with a carrier
•
socket for standard EEPROM or pre-programmed EPROM memory
module without a carrier
•
on-board EEPROM programming
User-accessible
free-running clock 5 ms resolution
User-accessible
wall clock/calendar 1 s resolution
Backplane interface
•
1771 I/O
•
supports block-transfers
•
multiple BASIC modules can reside in the same I/O rack and function
independently of each other
DH485
PRT2
PRT1
LED
Indicators
Reset