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The documentaion says that the output of digital logic can drive 10 ohms at 5V. Yet It seems it has no drive capability.

In this circuit https://www.circuitlab.com/circuit/w79959/digiana/

It cannot drive the transistor.

Any ideas?

You cannot switch the transistor on and off that fast using the circuit as you drawn it as at 130520.

If you slow down all your timings by a factor of 10 you will see that the circuit works as expected at lower frequencies.

"The documentaion says that the output of digital logic can drive 10 ohms at 5V."

Not quite. It says that the CL logic devices have a 0 to 5V output swing from a 10 Ohm source resistance. If you load such an output with 10 Ohms, you will see 2.5V across the load.

:)