I don't remember adding a specific API for that purpose.
There are a couple of workarounds. One is to look into the configuration. See the Pasti section of Steem.ini
and it would be obvious. Only issue here is that it might not be necessarily updated from the current state (but you can force an update it if you want).
The other is to inject some kind of ACSI command in the DMA channel to see if there is something. But that looks a bit ugly for a workaround
Anyway, let me know what you need and I'll implement something in the next update (that hopefully would be released shortly).