bacnet: unable to read or write multi-state

[davidderoo]

Hi all,
I want to read and write a value to a multi-state point in bacnet.
bit when I read the object I get a nil value. 
When I read it with yabe i get the value.
Here's my script:
-- object mapped to this event must have its data type set
Vloerkoeling = event.getvalue()

require('bacnet')
--write the value
bacnet.write(189073, 'multi-state output', 22829, Vloerkoeling, 15)
--read the actuale value
value = bacnet.readvalue(189073, 'multi-state input', 22829, 'present value')
log (value)


readind and writeing analog values an binary values works as a charm.
in attchment the yabe screenshot    

Kind regards,
David de Roo