5 serial communications – Rice Lake iQUBE2 Digital Diagnostic Junction Box User Manual
Page 13
Installation
9
2.5
Serial Communications
Serial communications between the iQUBE
2
and host or peripheral devices is provided by two ports.
• Port 1 provides onboard full-duplex RS-232 and full- or half-duplex RS-485 communications on connector J7.
A pair of switches on the circuit board (
S2
) set whether RS-232 or RS-485 is used and, if RS-485, whether full-
or half-duplex.
• Port 2 uses an option card installed in connector J9 to expand the communication capabilities of the iQUBE
2
.
Available option cards support fiber-optic, wired and wireless Ethernet, USB, and RS-232/RS-485 communi-
cations (see Table 2-6).
To attach serial communications cables, route the cable through the cord grip and wire to the connector on the
iQUBE
2
primary board. Use cable ties to secure serial cables to the inside of the enclosure.
Port 1 Communications
Table 2-2 shows the pin assignments for Port 1 connector J7.
Set the
S2
switches to select RS-232 or RS-485 and full (4-wire) or half duplex (2-wire) RS-485 communications
on Port 1.
The switches are only read on power-up; if switch settings are changed, cycle power to the iQUBE
2
before attempt-
ing to communicate using Port 1.
* Switch is only valid in RS-485 mode.
RS-485/422 Connections to Host 920i
The below tables show the connections needed for RS-485/422 communications between a host 920i and the
iQUBE
2
. 2-wire half duplex is available on Port 4 of the 920i. The 920i serial expansion card, PN 67604, must be
installed in the indicator for 4-wire RS-485/422 communications with the iQUBE
2
.
RS-485 is an addressed protocol. RLWS recommends using RS-422 if there is only one
iQUBE
2
system. See
920i
setup for port type.
J7 Pin
RS-232 Signal
RS-485 2-Wire
Signal
RS-485 4-Wire
Signal
1
GND1
GND1
GND1
2
RxD
—
Rx+
3
—
—
Rx–
4
—
A / +
Tx+
5
TxD
B / –
Tx–
6
—
—
—
Table 2-2. Port 1 Pin Assignments
OFF
ON
1
RS-485
RS-232
2*
2-WIRE
4-WIRE
Table 2-3. S2 Switch Settings
920i
Board
J10 Connector (Port 4)
iQUBE
2
J7 Connector
RS-422 Signal
Pin
Pin
RS-422 Signal
GND
1
1
GND1
RS-422 A
5
4
RS-485 A
RS-422 B
6
5
RS-485 B
Table 2-4. 2-Wire RS-422 Connections for
920i
Host
Note