3 remote baud rate, 4 remote address – Comtech EF Data SMS-758 User Manual
Page 63
SMS-758 Modem Protection Switch
Theory of Operation
MN/SMS758 Rev. 3
4–3
4.1.3 Remote Baud Rate
The eight position switch pack, SP1, on the M&C module programs the external remote
serial communications baud rate and parity. Set the switches to ON (nearer the PCB) or
OFF (away from the PCB) to select parity and baud rate.
SP1 switch position 1 (SP1-1) sets the parity:
•
“OFF” for even parity
•
“ON” for odd parity
SP1 switch positions 2, 3, and 4 (SP1-2, SP1-3, and SP1-4) set the baud rate as follows:
Baud
SP1-2
SP1-3
SP1-4
110
ON
ON
ON
150
ON
ON
OFF
300
ON
OFF
ON
600
ON
OFF
OFF
1200
OFF
ON
ON
2400
OFF
ON
OFF
4800
OFF
OFF
ON
9600
OFF
OFF
OFF
4.1.4 Remote Address
The switch connects to an RS-485 remote communication link. To communicate on this
link, each unit must have a unique address between 1 and 255. (0 cannot be a device
address, as it is the global address for all devices.) To set an address, use the 8-position
switch pack, SP2, on the M&C module.
Addresses are binary coded numbers:
•
Switch position 1 (SP2-1) is the most significant bit.
•
Switch position 8 (SP2-8) is the least significant bit.
To turn ON any switch, move it to the position closer to the PCB. For example:
Address
SP2-1
SP2-2
SP2-3
SP2-4
SP2-5
SP2-6
SP2-7
SP2-8
1
OFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
3
OFF
OFF
OFF
OFF
OFF
OFF
ON
ON
5
OFF
OFF
OFF
OFF
OFF
ON
OFF
ON
9
OFF
OFF
OFF
OFF
ON
OFF
OFF
ON
17
OFF
OFF
OFF
ON
OFF
OFF
OFF
ON
33
OFF
OFF
ON
OFF
OFF
OFF
OFF
ON
65
OFF
ON
OFF
OFF
OFF
OFF
OFF
ON
129
ON
OFF
OFF
OFF
OFF
OFF
OFF
ON
255
ON
ON
ON
ON
ON
ON
ON
ON