User manual
IEC61131 User and Reference Manual 
April 22, 2008     
593 
DF1 Addressing 
DF1 addressing is used by the master function when the specified port is configured for one 
of the DF1 protocols. Modbus addressing must be used in all other ladder logic program 
functions. 
DF1 addressing is used by function master_message when the specified port is configured 
for one of the DF1 protocols. The functions dbase, setdbase, setABConfiguration and 
getABConfiguration also support DF1 addressing.  
All DF1 addresses are absolute word addresses beginning with the first 16-bit register in the 
I/O database at address 0 and ending at address 21247. 










