Hello,
 
we are currently developing an android app that prints labels from both RW420 and ZQ520 portable printers.
We managed to discover both printer and retrieve their status but we are finding difficulties in getting the printer information from the RW420.
The ZQ520 works like a charm when trying to retrieve printer info using DiscoveryUtil.getDiscoveryDataMap(connection) while the RW420 returns this exception:
 
"Unable to parse the supplied discovery packet due to an invalid discovery packet length"
 
Any clue?
Thank you very much for the support
 
kind regards