I figured you guys may want to know, I am using the Pololu micro-metal geared 50:1 HP motors, as well as the Pololu Zumo Chassis (Tank treads…). The motors can run on 3-9v, and run with no load 6V@120mA, stall 6V@1.6A.
Here are the links.
Above are the Fritzing breadboard designs. The Voltage regulator ( 7805 - 5V ) was originally in both designs but I realised that It was not needed for the Arduino nano. The same schematic was used for the l293ne since it has the same pinout.
I am worried that the batteries may not be enough of a supply since the first pcb I made (etched) with the Nano was having supply issues (Partly since I used the 7805 and I powered the motors from the 7805’s output…). When the robot stalled, the nano would sometimes lose so much current that it would restart. That was fixed by removing the 7805 and using the batteries to directly power the l293d.
Some of you mentioned diode use, I am not to familiar with that. From the looks of my results, I think that maybe the motor driver is pulling to much current from the digital pins of the photon core. Im not totally sure though. I’m not sure if it really matters or not, but I am using the motors bi-directionally with the gpios (you may have noticed that possibility in my code).