Installation manual

184 | Simrad MX500
cables with an Ethernet switch (for more than two units).
You can purchase a pre-made LAN cross-over cable or
CAT5 Ethernet cable assembly from SIMRAD dealers or
you can make it up yourself using the diagram below.
LAN
RJ-45
Connector
LAN
RJ-45
Connector
1
2
3
4
5
6
7
8
1
6
7
4
5
6
7
8
Mx500
MASTER UNIT
Mx500
SLAVE UNIT
LAN TX +
LAN TX -
LAN RX +
NC
NC
No Antenna
Connected
LAN TX -
LAN TX +
NC
LAN RX +
LAN RX -
NC
LAN RX -
NC
NC
NC
NC
MX500 LAN Cross-over (Null) Cable Diagram
The interface between the two (or more) units takes
place over a high speed (100 Mbps) data link. The mas-
ter unit must be connected to the smart GPS antenna
unit (MX421, MX521, MX525, or MX575). The master unit
receives the position data then transfer it to the slave
unit(s) at a one second rate (the same as the position
calculation). Due to the high speed data link, there is vir-
tually no visible position delay between the two (or more)
units.
When the two (or more) units are first configured as
master and slave(s), the master listens for a configura-
tion polling message from the slave(s). Once the master
recognizes the slave’s polling message, the Common
Data Base (see Table below) is downloaded from the
master to the slave(s). This function also takes place
each time the units are powered up.