A nonvolatile memory device requires no additional dummy bytes between
receipt of a read instruction and a scanning out of data from a first
target memory location requiring incorporation of redundant memory bits.
A set of most significant redundant memory bits corresponding to a range
of regular memory locations may be read speculatively after a particular
set of the highest order address bits are received. After a complete
address is received, any requirement for substitution of redundant memory
bits is known. If no substitution is required, the regular memory
contents are read. Any requirement for a substitution of memory bits may
require replacement of the entire location. A regular read operation
continues after the first location is read. In this way, complete and
correct data for the memory location are available after receipt of a
read instruction with no additional delay for including any required
redundant memory bits.