Paul,

The four higher bits of PORTA are Inputs and when I checked out the levels on my PIC with my logic probe (set to TTL), using ~DCD would make the ports change status. BUT I have to try with another my PIC since one of my digits doesn't light-up normally making me think about a "little" problem... Should get a new one tomorrow.

About dimming, modifying the scan (refresh) rate of the digits is effectively not a good solution. It's working but, as said in another post, the strobe effect is also accentuated. I have modified my circuit and added transistors in each Common Anode connection. Those four transistors are then levelled by one additional transistor witch is LDR driven. At least, it works fine.

Dave,

My approach is maybe not a good one and any example/critic/suggestion is welcome. It's my first project involving a LED display, I didn't even know what multiplexing was before, so got still to learn more... My english is poor, what is a "gage set"?