READ_TOPO_ADDR: Reading the topological address
Original instructions
About us
Description of the function
The READ_TOPO_ADDR function extracts from an IODDT-type variable the topological address associated with it. This address is stored in a table.
This function applies to all channel-type IODDTs which can be used in a DFB.
The additional parameters EN and ENO may also be configured.
FBD representation
Representation:
LD representation
Representation:
IL representation
Representation: 
LD IODDT_Var
READ_TOPO_ADDR
ST Topological_Addr
ST representation
Representation:
Topological_Addr := READ_TOPO_ADDR(IODDT_Var);
Description of parameters
The following table describes the input parameters:
Parameter
Type
Comment
IODDT_Var
IODDT
Channel-type IODDT variable whose physical location (topological address) you wish to ascertain.
Examples: IODDT_Var of type T_COUNT_STD.
The following table describes the output parameters:
Parameter
Type
Comment
Topological_Addr
TOPO_ADDR_TYPE
Table of 5 integers representing the topological address of the IODDT_Var variable.
Topological_Addr[0]: bus number (0 if the channel is located on an in-rack module).
Topological_Addr[1]: device number (0 if the channel is located on an in-rack module).
Topological_Addr[2]: rack number.
Topological_Addr[3]: module number.
Topological_Addr[4]: channel number.