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Yet another H-Bridge

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Of course you are getting a short.
The PNP and NPN transistors in series both need series base resistors.
Right now you have the 0.7V emitter-base diode of the PNP directly in series with the 0.7V base-emitter diode of the NPN so their total is only 1.4V but you have it on the 5V supply.
 
I set separate resistors for each base, it improved the design as it started functioning but the high side transistors were all the time on even with pullup resistors.

I made some modifications and this is what I ended with. What do you think about it? It seems to be working. I do still have a doubt, will it brake the motor when both inputs are high? I don't think so.

By going back to ronv's design, I think that setting both inputs as high would cause a full short and destroy the chips. I hope I'm not wrong once again.
 
There are acouple of ways to prevent the top and bottom transistors on at the same time. Easiest of course is not to turn them both on at the same time. ;) Or add the diodes shown:
 
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