The Triscend E5 looks like a good option, the integrated programmable logic would be ideal for this job. Troule is that i am already using most of the available 20MIPs of the Cygnal micro.

From the datasheet, the E5 has a peak 10MIPs, it would not be quick enough to complete the switch duration calculations in the time available.

I think that CPLD is the solution although i am being attracted by the Intersil 82C54 (3 fully programmable 16bit timers). Any suggestions on where to learn about CPLDs?

Konrad