Rice Lake 920i Installation Manual V3.13 - Manual (Page 17)

Installation 11
Figure 2-5.
920i CPU Board, Showing Option Card Locations
2.3.4 Digital I/O
Digital inputs can be set to provide many indicator
functions, including all keypad functions. Digital
inputs are active low (0 VDC), inactive high (5 VDC).
Digital outputs are typically used to control relays that
drive other equipment. Outputs are designed to sink,
rather than source, switching current. Each output is a
normally open collector circuit, capable of sinking 24
mA when active. Digital outputs are wired to switch
relays when the digital output is active (low, 0 VDC)
with reference to a 5 VDC supply.
Table 2-4 shows the pin assignments for connector J2.
J11
PORT 1
J9
PORT 3
J10
PORT 4
J2
PIEZO
BUZZER
OPTION
J13
+6VDC
GND
GND
–6VDC
EXPANSION BUS
GND
R
S
-2
3
2 RxD
R
S
-2
3
2 TxD
GND / –20mA OUT
R
S
-2
3
2 RxD
R
S
-2
3
2 TxD
+20mA OUT R
S
-2
3
2 RxD
R
S
-2
3
2 TxD
+20mA OUT
R
S
-485 TxD +
R
S
-485 TxD −
+5VDC
GND DIO1 DIO2 DIO
3
DIO4
INTERFACE
BOARD
CONNECTION
POWER
SUPPLY
SW1
SW2
JP3
1
1 1
J5 J6
J7
DIGITAL I/O
J8
PORT 2
OPTION CARD
CONNECTOR
OPTION CARD
CONNECTOR
OPTION CARD LOCATIONS
J1
1
BATTERY
J15
BOOT
MODE
SLOT 1 SLOT 2
GND / –20mA OUT
REMOTE
SETUP
SWITCH
J2 Pin J2 Signal
1 +5 VDC
2 GND
3 DIO 1
4 DIO 2
5 DIO 3
6 DIO 4
Table 2-4. J2 Pin Assignments (Digital I/O)