ISIS I&C Manual
In-Store Information Server (ISIS) Installation Instructions • 7
1.14. Wiring Details
Each connector supports both full and half-duplex for
RS-485 signals on the DB-9 connectors are given in this
table:
.
1.15. Cable Diagrams
You will need to make cables to connect the DB-9P
connectors on the ISIS’s RS-485 adapter to the RS-485
device bus. Use the following cable diagrams and the
appropriate DB-9S (socket) connectors for attachment to
the ISIS ports.
1.15.1.RS-485 Full Duplex
An RS-485 bus wired for full-duplex is commonly
known as a “four-wire” bus. Cabling between devices uses
five conductors: two twisted-pairs plus a shield (ground)
wire.
Use the following cable pinouts to make a cable to
connect the ISIS using RS-485 full-duplex:
1.15.2.RS-485 Half Duplex
An RS-485 bus wired for half-duplex is commonly
known as a “two-wire” bus. Cabling between devices uses
three (3) conductors: a single twisted-pair plus a shield
(ground) wire.
Use the following cable pinouts to make a cable to
connect the ISIS using RS-485 half-duplex:
Table 1-4
- Pinouts for RS-485 ports on an ISIS RS-485 option (model NP-485).
NP-485 option DB-9 Connector, RS-485 Pinouts
DP-9P (male) connector
Pin
Name
Description
1
RD (A)
Receive Data A
2
TD (B)
Transmit Data B
3
TD (A)
Transmit Data A
5
GND
Signal Ground
9
RD (B)
Receive Data B
1
5
9
6
Figure 1-4
- RS-485 Full Duplex Cable Diagram
TD (A–)
Pin 3
TD (B+)
Pin 2
RD (A–)
Pin 1
RD (B+)
Pin 9
GND
Pin 5
RD (–)
RD (+)
TD (–)
TD (+)
GND
ISIS DB-9
RS-485 Bus
Figure 1-5
- RS-485 Half Duplex Cable Diagram
TD (A–)
Pin 3
TD (B+)
Pin 2
RD (A–)
Pin 1
RD (B+)
Pin 9
GND
Pin 5
(–)
(+)
GND
ISIS DB-9
RS-485 Bus
Jumper Pins: 1 & 3
2 & 9
Note: