13.6 SYSTEM-LEVEL DESIGN 649
requires a macrocell and if each Mealy output must also use a macrocell, the capability of the
PAL can be quickly used up for all but relatively small FSMs. Therefore, as a rule, it is best
to use registered PAL devices for one-hot designs of relatively small FSMs with only Moore
outputs. Used in this manner, registered PAL designs by the one-hot method offer quick,
convenient and reliable results, and without the need for K-maps or programming soft-
ware. See subsection 16.4.4 for information regarding synchronous one-hot programmable
sequencers.
If registered PLDs are to be used to implement large Mealy state machines by the one-hot
method, FPGAs are the best choice. A good example is the use of the 4000 series Xilinx ...