Furuno Felcom 250 Service Manual page 366

3. Enter "UpdateANT 1"
case letters for upper case letters. When you have entered the letters, press the
[Enter] key.
Note)
After the letters UpdateANT, enter a space, and then enter the PC COM port
number. COM port supports number 1 – 8.
4. When the COM port is opened and "boot ask" is displayed, turn the power of the
Communication unit on.
"boot ask" will be displayed until the power of the Communication unit is turned
on.
12.4 Updating the Software for the Antenna Unit
Note)
. Make sure to type in correctly – do not mistake lower
12-29