Robot Platform including h-bridges from $10 R/C Car

Step 5 Optional - add some data logic to reduce PWM needs

Note - I started down this path and even started on soldering up a miniboard with components, but found it to be too much work for too little payoff.  YMMV.

I was used to thinking of robot wheels in terms of two control pins, enable and direction.  The enable pin was where you put your PWM signal and direction was a simple binary for forward/reverse.  So you would need only two PWM signals for the robot, one for the left and one for the right.  Here's my quick and dirty digital logic for it.  I was going to use simple TTL circuits and a couple of 74HC Chips,

74HC04 - hex inverter
74HC08- quad 2-input AND gate

Now of course in my parts bin I don't have any AND gates, I only have NAND gates.  So I was going to use the leftover inverters from the hex to do the job, and the two chips would have everything I need.  That would work, but after playing around with it I decided to not go to the trouble - again YMMV.    I will say that on a solderless breadboard this is a lot of wires .