Re: EPICS Device Driver question

[Andrew Johnson <anj@aps.anl.gov>]

David Dudley wrote:
> Almost got the question entirely answered.  Just one more thing:
> Once the initialize routine is executed, can additional records be
> added?  For instance, can an additional I/O item by defined?  I'm not
> giving access to change addresses, but can I also infer that you
> can't add or delete any?

You can't run dbLoadRecords() after iocInit(), so you can't load any new 
records after initialization, and there is no infrastructure present to 
allow records to be deleted at runtime.  Your "I/O item" would usually 
map to a record, so you are correct that nothing can be added or deleted 
after that dset->init(1) call.

If you actually want to be able to do something like that you can do it 
by implementing the Extended Device Support and loading a bunch of 
'spare' records; when you need one you set its DTYP and INP/OUT field to 
the new Modbus address you want to talk to.  You can't rename the record 
at runtime though, so this is not a perfect solution.

- Andrew
--
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