x = not decoded. don't care, 0 or 1 can be used.
 
 only bit 0/D0 of the data written to the port controls motor state.
'''CPC 664/6128:'''
 x = not decoded. don't care, 0 or 1 can be used.
 
 only bit 0/D0 of the data written to the port controls motor state.
The I/O port decoding for the 6128 specific board is unknown.