1-7
System Overview
TI545/TI555 System Manual
The CPU has two communications ports; features and descriptions
are
listed below. Both ports are configured as Data Terminal Equipment (DTE).
•
Port 1 — RS-232 (9-pin male) is used to either program the CPU by an
IBM PC/AT compatible computer with APT or TISOFT, or to attach
equipment such as the Timer/Counter Access Module (TCAM), a
CVU100, or other operator interface using RS-232. The operator
interface can be up to 50 feet (15 m) away. A user supplied modem can
be used to extend this distance. Port 1 can also be used to attach a
printer.
•
Port 2 — RS-232/RS-423 or RS-422/RS-485 (9-pin male) is used to
communicate with operator interface equipment. Selection between
RS-232/423 and RS-422/485 is done with cabling options. Dipswitch 1
selects between RS-422 and RS-485 if 422/485 cabling is used. See
Chapter 3, Making Port Selection. Distance constraints are listed
below.
•
RS-232/RS-423 connection for operator interface up to 50 feet.
•
RS-422/RS-485 connection to 1000 feet.
The CPU has one Remote I/O port, (9-pin female) used to communicate
directly with remote base controllers (RBCs). This port uses a twisted,
shielded-pair RS-485 cable to communicate with RBCs.
Both Series 505 (see
NOTE
and Appendix C) and Series 500 I/O modules can
be connected to the TI545/TI555 CPU as remote I/O. The CPU is capable of
directly addressing the PPX:505–6851–A RBC in a Series 505 base
assembly, or the PPX:500–5114–A RBC in a Series 500 base assembly
intermixed in the same system. Both RBC models use shielded twisted-pair
cable. They can be placed up to 3300 feet from the CPU.
NOTE:
You cannot use some early model Series 505 I/O modules with a
TI545/TI555 CPU. Refer to Appendix C for details.
A permanent, rechargeable battery protects user memory and programming
during a power outage. Battery memory backup typically lasts six months
at temperatures ranging from 0
°
to 60
°
C.
Battery Damage: If the TI545/TI555 unit is left without power and
with the battery switch on for longer than six months, the battery
may be damaged to the point that it cannot be recharged.
Be aware that the battery will appear to charge, but the memory
backup time will be seriously degraded.
Return a unit in this condition to the factory for battery
replacement.
Communication
Ports
I/O Port
Battery Backup
CAUTION
!