1. A computer program product for translation of a virtual address into a translated address of a block of data in main storage in a computer system of a machine architecture, the computer program product comprising: a storage medium readable by said computer system, said computer readable medium storing instructions for performing: obtaining a virtual address to be translated; obtaining an origin address of a translation table of said hierarchy of translation tables; using an index portion of said virtual address to reference an entry in said translation table; determining whether a format control field in said translation table entry is enabled; and responsive to said format control field being enabled, performing: obtaining from said translation table entry a frame address of a large block of data in main storage; combining said frame address with an offset portion of said virtual address to form said translated address of a desired block of data within said large block of data in main storage, wherein said desired block of data consisting of one or more bytes of data; and accessing said desired large block of data addressed by said translated address.