there are those "amiga hardware reference manual" out there. if not already known to you, google for it, or try this:
Sure, I just need any 640x400 resolution with 1 plane. However, I'm really not familiar with Amiga hardware. If someone could write a proper initialization routine for such video mode, or at least point me to the relevant documentation, that would be big help.
DblNTSC has a 640x400 resolution (non interlaced). a driver from Aminet got some sources: http://aminet.net/package/driver/moni/newDblNTSC
maybe it is of any help. btw, nice project