RCG needs coherent handling of various ADC rates.
RCG UNDERSAMPLE has some contradictory ideas in code where UNDERSAMPLE >= 5 is treated differently than UNDERSAMPLE < 4, and UNDERSAMPLE = 8 is a special case.
The code should be changed into a coherent design, taking into account that 16 bit standard ADCs can only go up to 128 KHz. Any illegal configurations should be caught in the Perl compiler, not during run time or the C compiler.