Wiring The Serial Communications Ports - Rice Lake IQ plus 800 Installation & Operation Manual

NOTE:
RS-485 requires a U24 chip.
Bidirectional 20 mA CL requires
a U22 chip.

WIRING THE SERIAL COMMUNICATIONS PORTS

Terminal block J7 on the CPU board connects both the EDP (Electronic
Data Processing) port and the printer port. You must configure these ports
for your specific application (see Section 3, Configuration, for more
information). The EDP port handles full-duplex RS-232 or simplex 20 mA
current loop communication, with half-duplex RS-485 and full-duplex 20
mA current loop as optional features. The printer port handles simplex RS-
232 and 20 mA transmissions. Also, you can add another full-duplex serial
port to the system by installing the optional expansion board and auxiliary
serial port (see Section 8, Optional Features, for more information).
Table 2-2.
J7 – serial communications ports
Pin EDP
(RS-232)
1 —
2 —
3 —
4 —
5 —
6 —
7 —
8 —
9 RXD
10 —
11 TXD
12 GND
The following communications parameters (Table 2-3) apply to both the
EDP port and the printer port.
Table 2-3.
Serial communications parameters
• Continuous or Demand outputs
• 300, 600, 1200, 2400, 4800, 9600, or 19200 baud rate
• 7 data bits (with parity) or 8 data bits (no parity); 1 start bit and 1 stop bit
• None, odd, or even parity
• Line termination: <CR LF> or <CR>
• End of line delay up to 2550 milliseconds (2.55 seconds)
EDP Printer Printer
(20 mA CL) (RS-232) (20 mA CL)
— —
— —
— —
— — I– OUT
— TXD
— GND I+ OUT
— —
— —
— —
I– OUT —
— —
I+ OUT —
EDP EDP
(RS-485) (20 mA CL)
— — —
— — —
— — —
— —
— — —
— —
— 485-A I+ IN
— 485-B I– IN
— — —
— — I– OUT
— — —
— — I+ OUT
Installation 2-7