If you were perchance to have access to IDA Pro which supports what appears to be this processor you can in this case just open the binary and choose the correct processor type, it will then ask a load of other questions which in this case you can leave the default answers to (normally on a binary dump that doesn't often work, on 'normal' executables IDA works out everything for you).
Anyway it will then whizz off and start the disassembly, IDA works by actually following all the possible execution paths to disassemble the code and to avoid attempting to disassemble data, this can result in it missing a few parts, it is however the best disassembler out there and is pretty much the industry standard for this work.
It will then probably ask if you want to use proximity view (dependent on age of your version), say no to that, graph view is handy though (which it should default to). Another tip is under general settings turn on auto comments, it will then tell you what each mnemonic actually means which is useful if you aren't familiar with that processor type.