Furuno FAR-2107 Series Service Manual page 373

The figure below shows the interface of the AIS and HEADING SENSOR ports. Inputs
and outputs are isolated by LC1535 both on the TX and RX lines. The resistor of the
RD line is the terminating resistor. Loads on the talker side set ON/OFF of the
resistance. See page.4-39.
RD
TD
Fig. 7.3.3 I/F of AIS and HEADING SENSOR ports
Alarm outputs are contact signals by MOS-FET contact and items to be outputted as
alarms can be selected in [Menu] -> 3 -> 6, 7, 8 and 9. The EXT ALARM terminal on
the TB board operates as follows.
- ALM-1, 2, 3: Normally closed and the driver is U10-12 (PS7241 1B).
- ALM-4 : Normally opened and the driver is U9 (TLP176G TP).
See page.4-58.
2 3 11 14
ST1 ST2
GND2 Vcc2
420kHz
Vcc
1
RO
28
R
RE
27
LTC1535
DE
26
D
DI
25
GND
4
GND
Logic common
Note: Closed during power-off and initializing.
Note: Opened during power-off and initializing.
Q1-4
Terminal p.c.b
Fig. 7.3.4 I/F of ALM port
7-29
TERMINAL p.c.b
Position for setting of
GND2
terminating resistor
Floating
common
AIS port: [J656]
HDG port: [J655]
RDx-B
A
16
3
330 x 3
RDx-A
1 2
B
15
RO2
17
TDx-B
Y
13
TDx-A
Z
12
COMMON
SLO
18
400V max.
100mA max.
ALARM OUT x-0
4
1
ALARM OUT x-1
3
2
U9-12
7.3 Processor Unit: RPU-013