22 CLC - Configurable Logic Cell

The Configurable Logic Cell (CLC) module provides programmable logic that operates outside the speed limitations of software execution. The logic cell takes up to 256 input signals and, through the use of configurable gates, reduces those inputs to four logic lines that drive one of eight selectable single-output logic functions.

Input sources are a combination of the following:
  • I/O pins
  • Internal clocks
  • Peripherals
  • Register bits
The output can be directed internally to peripherals and to an output pin.
The following figure is a simplified diagram showing signal flow through the CLC. Possible configurations include:
  • Combinatorial Logic
    • AND
    • NAND
    • AND-OR
    • OR-XOR
    • OR-XNOR
  • Latches
    • SR
    • Clocked D with Set and Reset
    • Transparent D with Set and Reset
Figure 22-1. CLC Simplified Block Diagram
  1. See Figure 22-2 for input data selection and gating.
  2. See Figure 22-3 for programmable logic functions.