Furuno Felcom 250 Service Manual page 307

S4
(All OFF)
Normal: OFF, Research/inspection mode: ON
ON: Connection can be established to 172.31.16.1 (HUB CPU board) via
telnet.
Research/inspection command (loopback, ver) is available, and MAC
#1
address update is valid.
When the system is in research/inspection mode, HUBCPU firmware
updating is unavailable.
Normal: OFF, when maintenance mode is activated (HUB CPU only): ON
Set to ON when HUBCPU normal activation cannot be executed, and the
mode cannot be changed to maintenance mode.
HUBCPU firmware can be updated.
#2
This is the measure for when there had been a write error in the flash
ROM during development where DIP-SW 2 will have maintenance mode
forcibly activated for HUB CPU only, leaving MODEM CPU unchanged
and not activated in maintenance mode.
#3 To be set to ON for high-speed SIO loop back operations.
#4 Currently not used, to be set to OFF.
S2
To be set to OFF during normal operations, and to be set to ON during CPU
#1
boundary scan test.
To be set to OFF during normal operations, and to be set to ON during FPGA
#2
boundary scan test.
#3 Not used (circuit not connected either)
#4 Not used (circuit not connected either)
10.7 LED and DIP Switch for the Communication unit
Table 10.7.8 HUB board: S2 (DIP_SW for debugging the CPU)
Table 10.7.9 HUB board: S4 (for boundary scan test)
Function
10-39
Function