@BloodyCactus: It just works..The official level of a TTL "High" signal (according to Wikipedia) is from 2.0v - Vcc (5v), so a 3.3v high level would count as a 1 when read by a TTL IC. The CPLD only has to drive the first input signal of a TTL device; all ongoing signals would be at 5v. What is more important is the signals coming into the CPLD. If its (input) pins are not 5v tolerant there will be damage, but the part I am using (XC9536XL) is 5v tolerant.
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