[gmx-users] Translating .frcmod and .prep to .itp

[Timofey Tyugashev]

I have parameters for 8-oxoguanine in FRCMOD and PREP files. Adding 
information from .prep file to dna.rtp an creating a modified entry in 
dna.hdb is simple enough.
However I'm stuck now translating bond and angle data from .frcmod to 
.itp file, as its notation system is very different and its GROMACS 
manual section (5.3.3) lacks any substantial description of its formatting.
Is there any scripts or howtos for this, or at least a more detailed 
description  for ffbonded.itp?