OneRNG not working after reinstalling onerng_3.6-1_all.deb

[mark.diamond at yahoo.co.uk]

This is the result of running onerng.sh
> sudo /sbin/onerng.sh daemon ttyACM0

dd: error reading '/dev/ttyACM0': Resource temporarily unavailable0+0 records in0+0 records out0 bytes copied, 0.0189679 s, 0.0 kB/s
/sbin/onerng.sh: 80: kill: No such process


ttyACM0 was the device reported by dmesg ... but I don't understand what the various messages mean.

Because I don't have much idea what is going on, being unfamiliar with the intricacies of Linux USB devices, it might be worth adding the following:
(1) Installed the software from the .deb package
(2) On the http://onerng.info/onerng/ page, there are remarks about installing from either the .deb package OR a tarball ... and in the description about UNINSTALLING the tarball, reference is made to the file /usr/lib/udev/rules.d/79-onerng.rules . Should that file exist? It certainly isn't created by installing the .deb package !
(3) On a different note, not related to my problem, that page also mentions the command "udevadmin control reload-rules" . I think that that is an error and that the command has been spelt incorrect, and should be udevadm.

But I'm not sure that this get me any closer to getting my OneRNG working again :(
Mark