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© Sealevel Systems, Inc.
SeaI/O | SL9049 11/2021
Disabling the Rotary Address Switch & Limit Software Address Range Selection
Disabling the Rotary Address Switch and Limiting Software Address Range Selection is not available on
older SeaI/O units (Before Firmware Version 2). In addition, the following modules do not support it.
•
462
•
463
•
470
As noted earlier, rotating the rotary switch from a non-zero address to the address zero position will reset the
unit to the default state of address 247 and 9600 baud. There are many situations where this is not desirable.
In the event you wish to disable the rotary switch or simply limit the range of software selectable addresses that
may
be set, you can do so by sending the “WriteMultipleRegisters (function 0x16)” MODBUS command to the
unit. Address 300 (decimal) should contain the low order byte of the lowest address the unit will accept.
Address 301 will contain the high order byte. Once this command has been issued, the rotary switch will be
completely ignored by the firmware.
To reset the unit to “normal” operation, you can issue the MODBUS “Broadcast Reset Message (function 0x19).
This setting can also be configured through MaxSSD u
nder the “Range Configuration” tab, shown below on the
next page.