Not enough pins on my micro controller?
L293D has two channels and it can control two motors. One in each channel. The maximum current which can be drawn from a channel = 600 mA with peak output of 1.2 A. The current rating of the motor supply should be enough to drive both motors. The Vcc has to be at least 4.5 V says L293D data sheet. So powering it by 3.3 V would be a gamble as noise margins would be small. If you power it by at least 4.5 V, then you can make sure that anything over 2.5 V is enough to drive a logic high to enable pins.