In an old TAC Menta file, STATE members of SNVT_Switch inputs and outputs are assigned to DI/DO blocks. When editing existing SNVT_Switch I/O blocks, or adding a new one, it is not possible to select the STATE member from the drop-down list because the list is empty.
TAC Menta version 4.20 or higher
An application made in a version of Menta earlier than 4.20 would have had the STATE member of a SNVT-Switch declared as a digital input/output.
From TAC Menta version 4.20, both the STATE and VALUE members of the SNVT_Switch are declared as analog input/output.
Applications made with earlier versions of TAC Menta can still be downloaded with the latest TAC Menta version and will work correctly, provided you do not open the DI/DO block containing the SNVT_Switch member STATE and then exit the block dialog with the OK button.
If this occurs:
- Delete this DI/DO block
- Recreate the SNVT_Switch STATE using a AI/AO block instead
See TPI C-89-1-F5 for full details of this issue