eimaj12000 said:
Hi,
First of all sorry for the delay in replying but I wanted to make absolutely sure I had tested this to the best of my ability before posting. Secondly thanks for your help on this.
I'm having a small problem. The bridge circuit works 100% perfect and I tested this separately before doing anything else. Now, the problem I am experiencing is this:
Press S1 then S2 I get zero - no motor running
Press S2 motor runs clockwise but stops as soon as I hit S1
There's obviously a problem somewhere but I can't figure it out. I'm powering the whole thing from one 9V battery (the motor and the control section). I made sure I got the correct CMOS chips also but just can't seem to make this work. Any help would be greatly appreciated and if you leave me your paypal ID I will send some cash to cover your time.
Thanks again
OOoo, hi
Well looking over the circuit, it appears I made a couple of mistakes, sorry. Yes, the bridge is a tried and tested simple method for making a motor run either way on a single supply (not a dual +, GND, -supply).
As for the control circuit. A little explaination.....
The 'flip flop' part, I'm quite pleased with. S1 is the input to it, and S2 provides a clock. So, because both buttons are normally open...and pulled to ground, they are '0'. If you pressed S2 THEN S1, you are clocking in a '0' to the flip flop, then changing its input...so the output of the flipflop is '0', because the FF only reads the input when the clock goes from low to high. Any changes made to the input (S1) make no difference whatsoever unless S2 is pressed AFTER S1. So for that part at least, its all good.
Now, the problem arises with the 'OR' part. The output of the flipflop is only part of the problem as its output stays on if you pressed S1, then S2. The only way to change the output is to pressed S2 without S1 being pressed before, (so, S1 is open, it shows '0' to the input of the FF, and you clock that in with S2). I used an OR gate so that only when BOTH switches are released from a press, does it provice a '0', and therefore, when anded with the FF output (normal or inverted) turns this off.
There-in lies the problem though. Because its an 'OR', pressing either or both the switches makes the output of the OR gate '1', and therefore, because this is AND'd withthe flipflops output, whatever state the FF is in, sends the motor running. Now, because the motor runs in either direction, depending on the state of the flipflops output, if it isn't anded with something (like the output of our OR gate) then the motor will run continuously, and we can only change the direction if it.
Just wanted to get an explaination in first, circuit on its way. As I said, rough idea, not tested, and I made several mistakes
Blueteeth (buriedcode)