25.3.1 CLB Software Input Registers

The CLB Software Input (CLBSWINH:L) 8-bit registers can be used by user software to 'bit-bang' values into the CLB Look-up Tables (LUTs). The CLB module can be programmed to use the bits from the CLBSWIN registers as inputs to the LUTs.

CLBSWIN register synchronization occurs when the lower eight bits (CLBSWINL) are written by user software. When CLBSWINL is written, the contents of the all four registers are copied into holding latches.

Important: The CLBSWINH register must be written prior to writing the CLBSWINL register, otherwise the current values in each respective register will be latched once CLBSWINL is written.