It works! I built a circuit to drive two 7 segment LEDS from an ATmega32, displaying a byte in hex.
Using a pair of transistors I can use 7 output pins to light the 14 leds with another output connected to the transistor bases.
I saw the idea on a web-page somewhere but designed the circuit myself. Simple for most freaks perhaps, but since I am learning electronics this was an accomplishment.
I had to insert the diode between ground and the transistors. In fact I added a second one; now there is no more "bleed over". Displaying an 8 on the right caused some of the left digit segments to glow somewhat.
Can someone explain why the diodes are necessary?