A robust flexible logic unit (FLU) is targeted to be primarily, but not exclusively, used as an embedded
field programmable gate array (EFPGA). The unit is comprised of a plurality of programmable building block tiles arranged in an array of columns and rows of tiles, and programmed tile by tile and column by column, using latches that are sequentially programmed and locked using a lock bit that is part of the bit
stream provided. A scheme of odd and even clocks prevent latch transparency and ensures that loaded data is properly locked, to prevent overwrites. The robust FLU is further equipped with
cyclic redundancy check capabilities to provide indication of faulty column configuration. The invention also provides for splitting the single FLU into multiple independent reconfigurable FLU sections, with independent user
clock and reset, for implementing a plurality of independent functions or for establishing redundancy for critical functions.