ok so i have this h bridge and tx among other things and all worked fine on the usb but obviously i wanted to give it its own power supply so i got 2 9v batteries
connected them in series to give a dc motor 18 volts and used just one of the batteries to get 9v to power the board and bam, nothing happened and now the board isnt recognized by the computer and code does not run all i see the the "on" led on but thats it
the first picture is the circuit on a bread board then i built a case and body etc and all i did was switch from usb power to 2 9v batteries in series
with one end going to the H bridge and the other common ground to arduino and then the positive side of the first battery to my arduino, and i even tested with a multimeter to make sure it was giving me only 9volts and not 18.
so firast pic is on a breadboard second pic is basically the only change i made
in this second picture the batteries are connected directly to the motor but that was for time efficinecy i did not draw out the entire circuit
its actually going to the voltage-output on the h bridge , i literally changed nothing from the working circuit above except power source
By taking the shortcut in your 2nd picture, you make it difficult to understand what you connected as GROUND.
All components must share a common ground. Based on what you've drawn it looks like you floated the ground of the arduino.
To power an Ardiuno board with out the USB, you use a Wall type power adapter 9V. Here a picture ( see attachment ) to where you plug the DC plug.
Your board is damage ? Check the Troubleshooting section of http://arduino.cc
My opinion...Buy a new board.
I am sorry for the poor choice of word of my part. I just hope your board is working. Try to connect to the USB without your circuit connected, try to re-load "Blink" ...If it don't work...well ...I just feel sorry that.
Your statement implies a few things that are true but not accurate.
To power an Ardiuno board with out the USB, you use a Wall type power adapter 9V
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The ideal methods are USB or Barrel jack, but Vin is also option. (Such as what the OP did.)
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9V isn't the only voltage that can be used.
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What gets plugged into the barrel jack doesn't have to be a wall-wart power adapter. It certainly is a popular choice but not the only one, by far.
It looks like you connect arduino ground in between two battery, and as h-bridge and rx module
were still connected two "-" terminal of combine pack, they show up at the arduino inputs/outputs as -9V signals. atmega can't tolerate more than -0.5V.....
- The ideal methods are USB or Barrel jack, but Vin is also option. (Such as what the OP did.)
That part, I did not know.
- 9V isn't the only voltage that can be used.
I agree. 12 V will also work. The regulator on the board will accept that.
- What gets plugged into the barrel jack doesn't have to be a wall-wart power adapter. It certainly is a popular choice but not the only one, by far.
I agree. I use a PSU at 9 to 12 into the barrel jack.
As for the OP board, by changing the ATmega358 with a new chip with bootloader in, may fix his board ? I hope so. It is much cheaper to replace a chip than replacing the board.
yeah it is deffinately damaged because it no longer appears in the com ports even with absolutely nothing connected to it , and it geets veryyyy verry hot under the usb plug
i am now ust going to see if i can salvage any parts off of it perhaps the crystal or maybe the chip it self might still be good who knows ill have to check and i could also use the female headers hehehe. im waiting on a bunch of parts i ordered to make a couple of standalone costing about 5 dollars a piece i dont mind frying those but this was my first baby , it kind of hurt but i learned a lot from it and its loss is not in vain , i also think it is because i had no kickback diodes in place because i know this h bridge does not have any , but it was working fine without them while i was using a 12v power supply for the motor but then these 2 9v (18v) maybe just did it, and the ground was not floating everything had a common rail , i just did a poor job of illustrating that , but anywho next time i am going to wire a plug from the batteries and just have a separate battery for the arduino alone
Don't use those small 9V batteries for motors, they have a low current ability only and a high internal-resistance. (rechargeables are an exception).
Keep motor and Arduino supplies completely separate apart from a common ground connected at one common point.
You must decouple the motor driver chip supply well. All digital circuits need decoupling anyway, of course...
A wise precaution to protect the Arduino (should the motor controller be fried) is to use something like 2k2 resistors in series with all the logic connections between Arduino and motor driver.
it geets veryyyy verry hot under the usb plug
Yep ! It is shorted somewhere... What about the small 7805 in the Aduino board ? The ATmega could be test separated on a breadboard to see if it still working.
Keep motor and Arduino supplies completely separate apart from a common ground connected at one common point.
What about the use of opto-coupler ? Relays ?
To control a DC motor, 2 methode is use. 1. One supply --> reversed polarity at the motor. 2. Use of Dual Power Supply. Like to supply an op-anp ( +12 -- commun --- -12 ) Which one are you using ?
[quoteDon't use those small 9V batteries for motors, they have a low current ability only and a high internal-resistance.][/quote]
I agree with you.
I don't see how you can have learned anything when you say:-
but it was working fine without them while i was using a 12v power supply for the motor but then these 2 9v (18v) maybe just did it, and the ground was not floating everything had a common rail
However as you did such a poor job of describing what you actually did I suppose we will never know. However, what you described you thought you did was fine.
I get the feeling you were wiring it up with the power connected, is that right?
The commonest error beginners make is to think because a circuit appears to be working then it is all right. This is something you can learn from this.