Using The CAS Modbus Scanner to Read Modbus 6 Digit Address (Also Known As JBUS)

The older Modbus systems limited the number of objects of each type to 9999.

I.e. Max Input Register = 39999 and Max Holding = 49999

Whereas the protocol has space to read up to 65535 objects of each type. Older Modbus systems imposed a stupid validation and choked the address space to the 9999 limit. Newer systems like the CAS Scanner do not choke the address space and you can read any registers.

Example:

To read address Holding Register = 512345  (also known as Holding Reg with offset 12345 in PDU terminology)

 

Display of the request – we show both the 5 and 6 digit address.