2.1 Truth Table

By using the lookup table in the LUT, it is possible to generate any logical expression with up to three inputs. The inputs can be individually:
  • Masked
  • Connected to I/Os
  • Driven by peripherals:
    • Analog comparator output (AC)
    • Timer/Counters waveform outputs (TC)
    • USART
    • SPI
  • Driven by internal events from the Event System
  • Driven by other CCL sub-modules

Understanding how to use the truth table to generate the logical expression needed is the key to make the CCL work as intended.

Each TRUTH[x] line in the table will create one 3-input gate, and by choosing more than one TRUTH in the table it is possible to create complex logical expressions. Each combination of the input bits (IN[2:0]) corresponds to one bit in the TRUTHn register.

Table 2-1 2-3 2-9. LUT Truth Table
IN[2]IN[1]IN[0]OUT
000TRUTH[0]
001TRUTH[1]
010TRUTH[2]
011TRUTH[3]
100TRUTH[4]
101TRUTH[5]
110TRUTH[6]
111TRUTH[7]
Table 2-2. Possible Logic Blocks
IN[]TRUTHANDNANDORNORXORXNORNOT
000TRUTH[0]0101011
001TRUTH[1]011010x
010TRUTH[2]011010x
011TRUTH[3]011001x
100TRUTH[4]011010x
101TRUTH[5]011001x
110TRUTH[6]011001x
111TRUTH[7]1010100
0x800x7F0xFE0x010x960x690x01

Each TRUTH[x] chosen will be OR-ed together creating the final logical expression.

Figure 2-2.