Plenty of examples on the web, shouldn't be too hard to convert.
MSF has been covered here, worth a search.
Also worth posting a link to whatever DCF77 module you have so that even if nobody here has done it already, they can contribute without having to first find out what it even is.
“ The antenna at Anthorn is at latitude 54° 55' N, and longitude 3° 15' W.
The radiated power is typically around 17 kW and the horizontal radiation pattern is
substantially omnidirectional.
The signal provides a field strength exceeding 100 µV/m at a distance of 1000 km from Anthorn,
which covers the whole of the UK, and
it can be satisfactorily received throughout much of northern and western Europe. “
There are posts on the Forum
which show a Picaxe interfacing with an MSF receiver.
About halfway down is a description of the DCF77 protocol. It seems very similar to MSF in the UK and so should be similar to bit-bang and the overall protocol looks to be simpler.
Looking at the past MSF posts eclectic mentions is probably the best place to start, particularly in detecting length of pulses, detecting the minute marker, then building up from there.
Things will probably be easier and more understandable if you have a digital storage scope or a slow enough logic anaylser so you can see the transmissions over a minute or two but it should be possible to get it working without.